# A better technique for "ear" time alignment?



## fcarpio

There is a technique for adjusting your time alignment by ear in this forum. It has to do with playing white noise and listening for the "warble" effect as you adjust the time. That technique has NOT worked out for me as I suck when it comes to listen for the white noise "warble".

I just want to share another technique for time alignment that comes from another field I have an interest. Let me start by discussing the technique and how I applied it to car audio. The technique in question is a method for getting two (or more) microphones in phase. This technique is well known by musicians and recording engineers. It is used for miking guitar cabinets to get a fuller sound and it is also good for noise cancellation. Two microphones in phase record a bigger and fuller sound, specially good for metal (distorted) guitars. Two microphones out of phase are good for spoken word in a noisy environment where one mic will capture the voice and noise and the other only the noise with its phase inverted. when you add up the two signals you get "noise cancellation" and the voice remains intact.

How do you get the mics in phase? 
The human voice and the guitar are mono signals, but for this example I will pick on the guitar (no pun intended). We first get an idea of where do we like the mics to be by listening to the signal while we move them around in front of the guitar cab. Then we proceed to fix the first mic in place. Now the fun part, we are going to monitor the signal from both mics in "mono" with the second mic set to 180 degrees out of phase. We are going to start moving the second mic around the location that we liked until the monitored mono signal gets to the thinnest and weakest point. Now we fix the second mic in place and switch the out of phase setting back to normal and your mics are now perfectly in phase.

*How do I apply this technique to car audio?*
Easy. The only requirement is that you have to be able to feed a mono signal to your speakers and be able to isolate the sound of two speakers at a time. For this example I am going to assume you have a mono sub, so the first speaker pair to time align would be the sub and your right mid speaker. You are going to have to adjust the crossover a bit to get some overlapping frequencies, say 80Hz to 250Hz on both. Also try to keep the levels to sound even as it will make it easier to listen to both speakers at the same time. We are going to start the time alignment of the mid with respect to the sub. The technique only works if you can set the speaker that we want to time align out of phase, you may have to do this manually if you don't have a dedicated switch for it. You don't need white noise, your favorite song actually works best. In my opinion, a recording that has a bit of everything as far as frequencies go works very well (Bass for subs and mids, female voice for mids, guitar solos and cymbals for highs, you get the idea). Start delaying the signal of the mid a little at a time and listen for the signal to start cancelling. You are going to look for the point where it sounds its worst (weak and thin). Once you find it that will be your setting and you can now bring the mid back in phase. Now your right mid and subs are in phase. The next step will be to mute the sub and unmute the other mid. Don't forget to revert the settings on your crossover, both mids should have similar crossover settings now. Now you are going to do the same thing with the left mid, you are going to time align the left mid with respect to the right mid. The only time alignment you are doing at this point is to the left mid only as the right mid is already aligned with the subs. You are going to set the left mid out of phase and start increasing the time and listen for the signal to start to cancel and to sound weak, thin and unfocused. Find the worst sound and that is where you want to be. Now the fun part, bring the left mid back in phase and you will immediately hear the sound JUMP in front of you. That is because your two mids are PERFECTLY time aligned.

Now you are going to mute your right mid and unmute your left tweeter. What you want to try to do is to time align speaker that are opposite to each other (one left and one right) and try to have their frequencies overlap a bit but safely. If you have your crossover set to not overlap you will not be able to align a mid with respect to a sub, nor you will be able to align a tweeter with respect to a mid. If there is no frequency overlap there will be little or no cancellation to listen for when out of phase. Just repeat the process until you are done.

I hope this helps and please post your comments with the results you get.


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## hilander999

Interesting approach to say the least.



> [*Pinky & The Brain theme song*/]
> 
> NOW I CAN TAKE OVER THE WORLD!!
> 
> [/*Pinky & The Brain theme song*]


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## derickveliz

I'm going to have to try it!


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## derickveliz

derickveliz said:


> I'm going to have to try it!


I did! and it works!

D.


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## 24th-Alchemist

I like this idea. I like also that it doesn't require a lot of measuring equipment or modeling or analysis.

Thanks for the helpful contribution.


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## fcarpio

derickveliz said:


> I did! and it works!
> 
> D.


I am glad it worked out for you.


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## fcarpio

24th-Alchemist said:


> I like this idea. I like also that it doesn't require a lot of measuring equipment or modeling or analysis.
> 
> Thanks for the helpful contribution.


Thank you, I "Forrest Gumped" my way into it while doing something else.


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## ousooner2

Definitely trying this out tomorrow or this week! Always down for dialing in the TA even more


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## n03kiku

tonight i'll try this method..... :rimshot: ...  ....

thanks for the share....  ....

a few quetion...
when we doing this method..., what should the graphic equalizer set....? is it just "flat" ...?

thanks...  ...


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## fcarpio

n03kiku said:


> tonight i'll try this method..... :rimshot: ...  ....
> 
> thanks for the share....  ....
> 
> a few quetion...
> when we doing this method..., what should the graphic equalizer set....? is it just "flat" ...?
> 
> thanks...  ...


I don't think the EQ matters that much, mine was pretty much set the way I like it. The trick is to set the crossover to have some overlapping frequencies between the different size drivers to be able to hear the cancellation. Just do it safely and refer to your speaker's manuals to make sure you are playing them within a safe range.

EDIT: Actually, that is not a bad idea. You could use the EQ to boost the overlapping frequencies so you can hear them better.


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## n03kiku

fcarpio said:


> I don't think the EQ matters that much, mine was pretty much set the way I like it. The trick is to set the crossover to have some overlapping frequencies between the different size drivers to be able to hear the cancellation. Just do it safely and refer to your speaker's manuals to make sure you are playing them within a safe range.
> 
> EDIT: Actually, that is not a bad idea. You could use the EQ to boost the overlapping frequencies so you can hear them better.


thanks a lot..  ....

after tweeter out of phase and overlapping frequencies between let say for example right midbass and left tweeter and then the tweeter turn in to in phase again.., should i change the croosover again.., or it's not necessary anymore...?  .... and keep crossover overlapping...  .....

once again... thank you very much...  ....


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## Winno

How are you guys going with this?
I wont get a chance to try it until this weekend.


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## fcarpio

n03kiku said:


> thanks a lot..  ....
> 
> after tweeter out of phase and overlapping frequencies between let say for example right midbass and left tweeter and then the tweeter turn in to in phase again.., should i change the croosover again.., or it's not necessary anymore...?  .... and keep crossover overlapping...  .....
> 
> once again... thank you very much...  ....


Only change your x-over settings when needed for the TA. That is when you are setting the alignment for opposite speakers that don't have the same frequency range. When you are done bring them back to normal.

For example, if you are working on the sub and midbass, raise the sub frequency a little and lower the midbass a little to have them overlap. Do your TA and once you are done bring both back to normal. Now you are going to move to the two mid basses, here there is no need to change the crossover settings as these two speaker should cover just about the same frequency range. When done you are going to move to one midbass and one tweeter, here you will want to adjust the frequencies to overlap again. Lastly, before you do the two tweeters you need to bring the crossover settings back to normal.

In a nutshell, different speaker type, make the frequencies overlap. Same speaker type, bring crossover settings back to normal (same in both speakers) to overlap. Once you are done with the TA revert all your crossover settings to normal.


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## n03kiku

fcarpio said:


> Only change your x-over settings when needed for the TA. That is when you are setting the alignment for opposite speakers that don't have the same frequency range. When you are done bring them back to normal.
> 
> For example, if you are working on the sub and midbass, raise the sub frequency a little and lower the midbass a little to have them overlap. Do your TA and once you are done bring both back to normal. Now you are going to move to the two mid basses, here there is no need to change the crossover settings as these two speaker should cover just about the same frequency range. When done you are going to move to one midbass and one tweeter, here you will want to adjust the frequencies to overlap again. Lastly, before you do the two tweeters you need to bring the crossover settings back to normal.
> 
> In a nutshell, different speaker type, make the frequencies overlap. Same speaker type, bring crossover settings back to normal (same in both speakers) to overlap. Once you are done with the TA revert all your crossover settings to normal.


Wwwwwooowwww.....a very nice explain... Thanks a lot... really thank you so very much....  ..., and in about a few more minute..., I'll try this method...  ....


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## n03kiku

Well..... I just did this technique... and "woowwww".... awesome...  ....

First I try to set both midbass which left midbass in phase and right midbass out of phase.., then I play the white noise (coz its already nigt and if I play my favorite song it would be annoying my neighboard  ) untill I hear the weak and thinnest sound....

And then left tweeter out of phase and right midbass in phase.....

And the last is left tweeter in phase and right tweeter out of phase....

Oke......now put all of them in phase...., and result is the sound of the sub woofer, midbass and tweeter are more detail and more focus...., more loud but not too loud off course...  .....

since I learn to hear the noise...., somehow that make me much easier to find the weak and the thinnest sound..., coz if you find that kind of sound, that make you will hear the difference after all speaker are in phase....  ......

Thanks for every share that already gave for us...  ....

Regards.... Nuki... Jakarta - Indonesia ....  ....


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## ousooner2

Probably going to try this out today. I'll report back


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## RustyWedges

subbed...


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## trojan fan

Looks like you got a few buyers......


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## fcarpio

trojan fan said:


> Looks like you got a few buyers......


LOL, yes. Time will tell if this technique sticks.


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## adrenalinejunkie

Will consider this once I go 3 way active.
Which track can you recommend that has "a bit of everything as far as frequencies go "? Thanks for sharing.


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## fcarpio

adrenalinejunkie said:


> Will consider this once I go 3 way active.
> Which track can you recommend that has "a bit of everything as far as frequencies go "? Thanks for sharing.


I don't know, I was just saying. A bunch of CDs would work well.


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## n03kiku

damn it really works....

left midbass (in phase) ===> right midbass (out of phase) ...
right midbass (in phase) ===> left tweeter (out of phase) ...
left tweeter (in phase) ===> right tweeter (out of phase) ... and final...
right tweeter (in phase) .....

damn...it seems like main vocal like in the center...., and the backing vocal feels like somewhere in the back of main vocal or sometime just like in front me...

yeesss..... the stage are made..... :blush: ...

or may be there is something i missed.... please teach me....  ....

:rimshot: ...


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## fcarpio

n03kiku said:


> damn it really works....
> 
> left midbass (in phase) ===> right midbass (out of phase) ...
> right midbass (in phase) ===> left tweeter (out of phase) ...
> left tweeter (in phase) ===> right tweeter (out of phase) ... and final...
> right tweeter (in phase) .....
> 
> damn...it seems like main vocal like in the center...., and the backing vocal feels like somewhere in the back of main vocal or sometime just like in front me...
> 
> yeesss..... the stage are made..... :blush: ...
> 
> or may be there is something i missed.... please teach me....  ....
> 
> :rimshot: ...


If the stage is made, then you are there. 

Now you need to do this for the EQ: http://www.diymobileaudio.com/forum...rs/33740-simple-way-tune-courtesy-cmusic.html


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## n03kiku

fcarpio said:


> If the stage is made, then you are there.
> 
> Now you need to do this for the EQ: http://www.diymobileaudio.com/forum...rs/33740-simple-way-tune-courtesy-cmusic.html


 .... I don't have that CD's ....  ....

 .... but really apreciate and many thanks for the time allignment lesson..., that helping much from my car audio sounding...  ...


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## fcarpio

n03kiku said:


> .... I don't have that CD's ....  ....
> 
> .... but really apreciate and many thanks for the time allignment lesson..., that helping much from my car audio sounding...  ...


For some reason I think you can get that CD or a similar one here in the forum. I have seen one going around that has test tones created by a member. This member is making it available for free. Ask around or try searching for it.


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## adrenalinejunkie

This method is for a driver seat listener, right? How do we go about this if we want it to sound good for driver and passenger seats? I'm assuming to do the process starting with the left mid driver/subwoofer for a passenger seat tune...
Sorry for the stupid questions, new at tuning...


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## fcarpio

adrenalinejunkie said:


> This method is for a driver seat listener, right? How do we go about this if we want it to sound good for driver and passenger seats? I'm assuming to do the process starting with the left mid driver/subwoofer for a passenger seat tune...
> Sorry for the stupid questions, new at tuning...


Interesting question. I think you may have to repeat this process two times (passenger and driver seat) and save the settings in different presets. This will allow your passenger to have the correct TA settings, but you will no longer be time aligned. Alternatively you can just turn the TA off when you have passengers, but I don't think that would make too much of a difference to them. In my car the TA is for me only and I leave it on at all times. When I want to show off to a friend I let him/her sit in the driver's seat for a demo. The TA I describe is only for one spot, as most are (I think).


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## derickveliz

fcarpio said:


> Interesting question. I think you may have to repeat this process two times (passenger and driver seat) and save the settings in different presets. This will allow your passenger to have the correct TA settings, but you will no longer be time aligned. Alternatively you can just turn the TA off when you have passengers, but I don't think that would make too much of a difference to them. In my car the TA is for me only and I leave it on at all times. When I want to show off to a friend I let him/her sit in the driver's seat for a demo. The TA I describe is only for one spot, as most are (I think).


*For P99 owners* just switch from Left to Right stage in the menu, or both (not my favorite) but like *fcarpio says.*.. to show off I have my guest *take the sweet spot * on the drivers side! 

D.


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## Winno

Have just used this method on a friend's car.
His system is a full Morel 4 way with CDM88 mids and Piccolo tweeters in pillars, Elate 9s in the doors and an Ultimo 12 in the boot/trunk.
I used mono pink noise because it was the only mono track we had.
We also had to physically change some drivers' cables around to reverse the phase because the Clarion HX-D2 allows rev of phase between pass bands but not between left and right.

Results are superb in two areas;
1. Imaging and stage spread/width are significantly improved as you would expect.
and a surprise by product;
2. The overall spectral balance has also improved significantly because of a lack of phase anomalies between each driver compared to previous tunes using other methodologies. The sound now has a smoothness about it that didn't exist previously. This is because the drivers are tuned to a reference which is the driver before it, which leads right back to the sub. We now have no rev phase set on any drivers in the system as all drivers are working together.
I'm sure that if we RTA'd things, it would show a much smoother response across the entire 20 to 20.

Thank you for your post.
Much appreciated indeed.

IMO, this thread is worthy of a 'sticky' permanently at the top of this forum.


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## SouthSyde

Instead of flipping the phase and listening for the thinnest sound then flipping it back, Cant you leave the phase all correct and listen for the fullest most focused sound?


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## hilander999

SouthSyde said:


> Instead of flipping the phase and listening for the thinnest sound then flipping it back, Cant you leave the phase all correct and listen for the fullest most focused sound?


Yes you can and there is a detailed thread on doing exactly that, However it's no where near as obvious where the sound is the "Fullest" because the 2 sound waves combine and create a large "Full Spot"

Finding the thinest spot is very obvious because the waves cancel each other out and it comes to an almost exact point in space where you will hear the loss of common tones between the 2 speakers.


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## cobra93

I'll have to give this a try as well.

I don't seem to have a problem with left to right on the same speaker pair, but getting the sub synched to the mid bass and the widebanders to the mid bass has left me guessing.


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## Winno

cobra93 said:


> I'll have to give this a try as well.
> 
> I don't seem to have a problem with left to right on the same speaker pair, but getting the sub synched to the mid bass and the widebanders to the mid bass has left me guessing.


I experienced a similar issue at first. 

Use your cross overs to limit the pass band of the two drivers in question to play the band where they are both playing the same frequencies. 

If the drivers are playing sound far outside of this area, the sound outside the mutual cross over point will not be cancelled to the same degree which then makes it more difficult to determine any change in sound. 

It's a little more fiddling to do but it does make things easier to hear.


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## cobra93

In thinking more about this, I would assume I should start with the driver farthest from me.
This would eliminate backtracking.
Does this sound correct?

My system is in my sig.
The 2 subs are behind me and fire toward the outsides of the truck.
The drivers side sub is the closest to me followed by the dr. side widebander, dr. side mid bass, pass. side sub, pass. widbander and then pass. side mid bass.
Start with the farthest and continue to the closest?
Where would you start and what order would you use?

I ask this because the drivers in my system could over lap frequencies without damage as opposed to a system with tweeters.


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## stochastic

For the order that one should begin, it's probably easiest to start with the midranges (something that can hit 500-800Hz would be a great start point) this size of wavelength ~24" is probably the best range to get a general region tied down. The other factor that should be considered in this technique is that there are two ears roughly ~6" apart from one another (the wavelength of ~2000-2200Hz) so different frequencies will have smaller sweet spots than are detectable from this technique. A great way around this would be to plug one ear with an earplug and move the open ear to where the centre of your head would be.

Another great way to figure out which drivers to start with would be to physically measure your PLD's and start with the group that has the largest PLD. Work your way to the ones with the smallest PLD. In general you'd want to try to get everything tuned against one fixed driver (i.e. that's your control mid that is closest to you so will naturally take the least delay), this will prevent any slight offset from compounding.


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## Winno

A colleague of mine suggests that the 'zero' or 'reference' driver should always be the driver that is furtherest away from which ever seat you want to be the hot seat as it were. 

In most systems this is the subwoofer and that's why I started with this first when I tried the OP's tuning suggestion. 

And if you think about it, this makes sense because you want to delay any other driver to match it because all the others are closer afterall. 

In my system, because my sub will be between the two front seats, I'll actually want to have my passenger side midbass (door mounted) or wide band mid/tweeters (A pillars) as the reference point because they'll obviously be further away. 

Other than that, the same principles that the OP suggests will apply.


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## stochastic

Winno said:


> A colleague of mine suggests that the 'zero' or 'reference' driver should always be the driver that is furtherest away from which ever seat you want to be the hot seat as it were.
> 
> In most systems this is the subwoofer and that's why I started with this first when I tried the OP's tuning suggestion.
> 
> And if you think about it, this makes sense because you want to delay any other driver to match it because all the others are closer afterall.
> 
> In my system, because my sub will be between the two front seats, I'll actually want to have my passenger side midbass (door mounted) or wide band mid/tweeters (A pillars) as the reference point because they'll obviously be further away.
> 
> Other than that, the same principles that the OP suggests will apply.


Quite right, my last post that suggested the closest driver being the 'zero' was a backward thought. The furthest driver will be the best 'zero' to tune everything off of.


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## cobra93

Thanks for the confirmation, Winno and stochastic.

I give ~250 hertz a try and see what happens.


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## fcarpio

hilander999 said:


> Yes you can and there is a detailed thread on doing exactly that, However it's no where near as obvious where the sound is the "Fullest" because the 2 sound waves combine and create a large "Full Spot"
> 
> Finding the thinest spot is very obvious because the waves cancel each other out and it comes to an almost exact point in space where you will hear the loss of common tones between the 2 speakers.


I couldn't have said this better myself, thank you.


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## fcarpio

adrenalinejunkie said:


> Will consider this once I go 3 way active.
> Which track can you recommend that has "a bit of everything as far as frequencies go "? Thanks for sharing.


You can do this with a 2-way system, or with an X-way system for that matter.


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## Cruzer

i have a poorly trained ear, but i tried this yesterday. its hard for me to truly know whats the weakest or thinnest sound. i guessed, but i dont know if im right, close, or way off.

regardless, it was a huge improvement on sound. the stage sounds further towards the hood, centered, etc.

the mids and sub now sound well blended. so much so that i feel like i need to turn the sub up because its disappeared.

random noob question, i know everyone's driving different vehicles, even in same vehicles, some people have tweeters different spot, say not stock, etc.

but i have a jeep grand cherokee 4 door suv. if someone else has a 4 door suv similar size, if they have the mids t/a at 10 inches for left and 30 inches for right, and mine is like 20 inches for left and 50 for right, does that mean mines wrong, bad, off, or can it be that drastic a difference between cars. or is it differences in ears?


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## ousooner2

What's the best way to swap phase on the speakers?? Literally just swapping the (+) and (-) on the amp for the specific speaker that needs to be swapped?

I can just turn off the other speakers via 3sixty.2 while using the 2 speakers in testing. Definitely want to try this out soon.


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## ousooner2

bump...


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## hilander999

Cruzer said:


> if someone else has a 4 door suv similar size, if they have the mids t/a at 10 inches for left and 30 inches for right, and mine is like 20 inches for left and 50 for right, does that mean mines wrong, bad, off, or can it be that drastic a difference between cars. or is it differences in ears?


Installation is everything. (period)

Time Alignment allows the same audio pathlength in an odd sized room (car/truck/whatever) where the speakers are not in optimal placement.

Even if your install is "Perfect", speaker locations are not and this is why we adjust the TA for each individual speaker based on one fixed point which should be the speaker that is furthest away from the listening position.

Yes, drastic differences in TA are normal, different crossover slope, amount of amplification, speaker type and aiming is the most critical. Even one degree different in speaker aiming will use different TA, not to mention that its also reflecting off anything in its pathway, so there is no correct number as for time alignment.

For example, a tall person will have different prefferances then a shorter person in the same vehicle because thier ears are not in the same place while sitting in the "Hot Seat".

Thats as simple as I can explain it.


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## hilander999

ousooner2 said:


> What's the best way to swap phase on the speakers?? Literally just swapping the (+) and (-) on the amp for the specific speaker that needs to be swapped?
> 
> I can just turn off the other speakers via 3sixty.2 while using the 2 speakers in testing. Definitely want to try this out soon.


You have to be able to turn off speakers for this method to work, if your dsp allows for this then it's fine, most will have to dissconnect the speaker wires from the amp, or pull the fuse.

If your running an active setup, swap the wires at the amp itself.
For passive crossovers, swap the wires comming out of the crossover.

Please don't "Bump" a thread after only 5 hours. You will always get answers in a popular thread, and it seems most of the users here are on at night more then in the daytime.
Now if someone skips your question, then by all means BUMP away.


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## Winno

ousooner2 said:


> What's the best way to swap phase on the speakers?? Literally just swapping the (+) and (-) on the amp for the specific speaker that needs to be swapped?
> 
> I can just turn off the other speakers via 3sixty.2 while using the 2 speakers in testing. Definitely want to try this out soon.


It doesn't really matter how you do it. 

If your processor allows you to switch the phase on single drivers, just do it that way. It gives the same result as physically changing wires around and is more than likely much easier. 

My Clarion HX-D2 doesn't allow single driver switching so I would have to switch wiring physically. 
I personally find it much easier to hear the focus you get when the drivers are tuned when in phase rather than the diffuse and unfocused sound when one driver is out of phase. 

Use what you prefer.


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## Cruzer

hilander999 said:


> Installation is everything. (period)
> 
> Time Alignment allows the same audio pathlength in an odd sized room (car/truck/whatever) where the speakers are not in optimal placement.
> 
> Even if your install is "Perfect", speaker locations are not and this is why we adjust the TA for each individual speaker based on one fixed point which should be the speaker that is furthest away from the listening position.
> 
> Yes, drastic differences in TA are normal, different crossover slope, amount of amplification, speaker type and aiming is the most critical. Even one degree different in speaker aiming will use different TA, not to mention that its also reflecting off anything in its pathway, so there is no correct number as for time alignment.
> 
> For example, a tall person will have different prefferances then a shorter person in the same vehicle because thier ears are not in the same place while sitting in the "Hot Seat".
> 
> Thats as simple as I can explain it.


thanks tho i like how u say installation is everything then u say even if install is perfect u still have to t/a. pretty much made install everything comment useless lol


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## hilander999

Cruzer said:


> thanks tho i like how u say installation is everything then u say even if install is perfect u still have to t/a. pretty much made install everything comment useless lol


Perhaps you should read it again.

A lot of nice sounding systems have no TA at all.
TA allows for precise adjustment for your listening position, which is certainly not centered between the speakers in a vehicle.

If your install sounds like crap before Time Alignment, you can be pretty sure it's still going to sound like crap afterwords.

In short "Garbage In = Garbage Out", so YES, INSTALL is everything.


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## Cruzer

hilander999 said:


> Perhaps you should read it again.
> 
> A lot of nice sounding systems have no TA at all.
> TA allows for precise adjustment for your listening position, which is certainly not centered between the speakers in a vehicle.
> 
> If your install sounds like crap before Time Alignment, you can be pretty sure it's still going to sound like crap afterwords.
> 
> In short "Garbage In = Garbage Out", so YES, INSTALL is everything.


u get what i was saying...


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## hilander999

Cruzer said:


> u get what i was saying...


Sure, everything about car audio is counter intuitive.
But I never said "u still have to t/a" because it is not a cure-all by any means.

Now if your system already sounds great, the results from proper Time Alignment are simply amazing. Which still does not mean it is "Required".


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## Cruzer

hilander999 said:


> Sure, everything about car audio is counter intuitive.
> But I never said "u still have to t/a" because it is not a cure-all by any means.
> 
> Now if your system already sounds great, the results from proper Time Alignment are simply amazing. Which still does not mean it is "Required".


yes i was just trying to get the point across and u got it...


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## dietDrThunder

Apparently I'm deaf, because this method was a complete bust for me. I was 100% unable to find any clearly defined 'weak spot' with music, and while I was more successful with pink noise, I was still unable to find even ballpark settings. My car is in the garage right now going back through the auto-tune so that I can see what settings it comes up with.

A couple of questions...

1. In the OP, at the end there is says "Now you are going to mute your right mid and unmute your left tweeter. What you want to try to do is to time align speaker that are opposite to each other (one left and one right)..." This comes after the step where both mids are unmuted.

This makes no sense to me. If I mute the right mid and unmute the left tweeter, I've got the left mid and tweeter on only. That isn't 'opposite. ???

2. Using pink noise I was able to hear various doppler shifts and harmonics, but I never came anywhere near figuring out any patterns that told me that I was 100% out of phase. What am I missing here?

3. On the mid to mid adjustment, I could go from 0 delay to max delay and only hear tiny (but I did hear them) changes. When I tried music, the differences were even tinier...waaay too small to make even a guess at what the right delay might be.

4. My HU has distance as the measure, not time. I assume that means I need to adjust all distances to the highest value, and tune that number down (down = more delay I assume) yes? This should mean that after I've set the sub v. right mid, I should then adjust the left mid to the same delay (distance) then adjust down from there, correct? 

cliffs: I admit I thought I was gonna get a TA hu and badda-bing, ultra-sound. This is hard. My system sounded quite good IMO considering how modest it is, before the hu change. I had 0 imaging, which is why I changed. So far I've tuned for about 3 hours and have yet to come anywhere near the tonality I had with my $180 Clarion hu.

Thanks for any help, and thanks for letting me vent


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## cobra93

One quick thought as I don't see what your system consists of.
If you're aligning a mid and a tweet, regardless of left/right or both same side, are they playing the same frequencies?
Do they overlap? 
If they don't you wouldn't cause cancellation and the sound won't become"thin".


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## dietDrThunder

cobra93 said:


> One quick thought as I don't see what your system consists of.
> If you're aligning a mid and a tweet, regardless of left/right or both same side, are they playing the same frequencies?
> Do they overlap?
> If they don't you wouldn't cause cancellation and the sound won't become"thin".


Ya I adjusted the xovers to get as much overlap and as little one-way signal as possible.


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## fcarpio

dietDrThunder said:


> Apparently I'm deaf, because this method was a complete bust for me. I was 100% unable to find any clearly defined 'weak spot' with music, and while I was more successful with pink noise, I was still unable to find even ballpark settings. My car is in the garage right now going back through the auto-tune so that I can see what settings it comes up with.
> 
> A couple of questions...
> 
> 1. In the OP, at the end there is says "Now you are going to mute your right mid and unmute your left tweeter. What you want to try to do is to time align speaker that are opposite to each other (one left and one right)..." This comes after the step where both mids are unmuted.
> 
> This makes no sense to me. If I mute the right mid and unmute the left tweeter, I've got the left mid and tweeter on only. That isn't 'opposite. ???
> 
> 2. Using pink noise I was able to hear various doppler shifts and harmonics, but I never came anywhere near figuring out any patterns that told me that I was 100% out of phase. What am I missing here?
> 
> 3. On the mid to mid adjustment, I could go from 0 delay to max delay and only hear tiny (but I did hear them) changes. When I tried music, the differences were even tinier...waaay too small to make even a guess at what the right delay might be.
> 
> 4. My HU has distance as the measure, not time. I assume that means I need to adjust all distances to the highest value, and tune that number down (down = more delay I assume) yes? This should mean that after I've set the sub v. right mid, I should then adjust the left mid to the same delay (distance) then adjust down from there, correct?
> 
> cliffs: I admit I thought I was gonna get a TA hu and badda-bing, ultra-sound. This is hard. My system sounded quite good IMO considering how modest it is, before the hu change. I had 0 imaging, which is why I changed. So far I've tuned for about 3 hours and have yet to come anywhere near the tonality I had with my $180 Clarion hu.
> 
> Thanks for any help, and thanks for letting me vent


1 - typo, you want opposites.

2 - did you use an overlapping mono signal? If you can't hear the differences too much then overlap a bit more.

3 - See #2 above.

4 - I guess furthest away = more delay but I couldn't tell you for sure.


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## dietDrThunder

fcarpio said:


> 1 - typo, you want opposites.
> 
> 2 - did you use an overlapping mono signal? If you can't hear the differences too much then overlap a bit more.
> 
> 3 - See #2 above.
> 
> 4 - I guess furthest away = more delay but I couldn't tell you for sure.


1. Cool...thanks

2. the file says that it's mono, so ya. The music wasn't...I don't have a way to make mono files atm, but the pink noise says it is.

3. See 2

4. I firured that part out...higher distance = lower delay (the max distance = 0 delay) which makes sense.


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## fcarpio

dietDrThunder said:


> 1. Cool...thanks
> 
> 2. the file says that it's mono, so ya. The music wasn't...I don't have a way to make mono files atm, but the pink noise says it is.
> 
> 3. See 2
> 
> 4. I firured that part out...higher distance = lower delay (the max distance = 0 delay) which makes sense.


You don't have to "make" a mono music file. Just get a cheap Y splitter and take one (mono) channel from your source and split it over the two channels you are aligning.


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## Cruzer

i thought the op said music was the best option as its dynamic and playing a wide spectrum?

i too struggled to hear it thinning, but my tweeter doesnt cross well to my mids. but i even had trouble with the mids and sub, sub playing up to 100hz and mids playing 80hz and up

i just took at as my ears not really trained for this stuff and guessed best i could


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## fcarpio

Cruzer said:


> i thought the op said music was the best option as its dynamic and playing a wide spectrum?
> 
> i too struggled to hear it thinning, but my tweeter doesnt cross well to my mids. but i even had trouble with the mids and sub, sub playing up to 100hz and mids playing 80hz and up
> 
> i just took at as my ears not really trained for this stuff and guessed best i could


You must be doing something that is off, because the thinning is pretty evident. That is the beauty of this technique. If I can do it, then you can do it. 

What do you mean by tweeter not crossing well to your mids?

Remember: mono signal, overlapping frequencies, opposite sides. You WANT cancellation.


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## dietDrThunder

I think he was saying that he doesn't have much overlap to work with.


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## fcarpio

dietDrThunder said:


> I think he was saying that he doesn't have much overlap to work with.


Oh, I see. In that case I would recommend you use a CD that has test tones. That way you can use the test tone that fits between the overlapping frequencies. I have NOT tried this technique with white noise, it may work with a smaller overlapping frequency range.

I may have a test tone CD that I could make an ISO and uploaded somewhere so you can use it. I have to find it though...

EDIT: I re-read the post and I get it. Try this: If you have a phase knob somewhere in your system this will work. Align the mids and the tweeters using my method and leave the subs for last. Bring everything back to normal listening settings (correct phase, crossover and levels). To align the subs sweep the sub's phase knob starting at 0 all the way to 180 until you find the bass signal is at its strongest. Voila! You are done.

I have tried this myself and I know it works.

Good luck with your TA.


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## Lars Ulriched

subscribed...


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## ousooner2

Can't wait to try this method and see what I come up with. 

For everyone who needs to convert something to mono...download _*FreeMusicConverter*_. Super simple and will do tons of different conversions.


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## fcarpio

ousooner2 said:


> Can't wait to try this method and see what I come up with.
> 
> For everyone who needs to convert something to mono...download _*FreeMusicConverter*_. Super simple and will do tons of different conversions.


Have you tried it yet? How did it go? Thanks for the tip on the converter...


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## basshead

I was looking for a way to do TA with my RTA, thanks for giving me the missing piece of the puzzle!

Now, I didn't read the entire replied, but i would like to add that changing xover and EQ will affect phase and subsequently affect your TA. 

Also the main reason I want to use the RTA is because your ears can play trick on you, you will realise it only the next morning when your ears are fresh again and start listening to your system and think it sound like ****. With the RTA you get this problem out of the way and get consistent measurement, let you measure and L/R level and quickly readjust your TA after playing with your Xover or EQ. 

No i didn't try it yet, but that's my theory lol


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## fcarpio

basshead said:


> I was looking for a way to do TA with my RTA, thanks for giving me the missing piece of the puzzle!
> 
> Now, I didn't read the entire replied, but i would like to add that changing xover and EQ will affect phase and subsequently affect your TA.
> 
> Also the main reason I want to use the RTA is because your ears can play trick on you, you will realise it only the next morning when your ears are fresh again and start listening to your system and think it sound like ****. With the RTA you get this problem out of the way and get consistent measurement, let you measure and L/R level and quickly readjust your TA after playing with your Xover or EQ.
> 
> No i didn't try it yet, but that's my theory lol


Absolutely, EQ (not sure about x-over) will affect your TA, but I think this should be done as a step for fine tuning rather than your main TA method. I think my method will take care of 95% of the TA, and this is just a guesstimate I pulled out of my...


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## deesz

Subscribed.


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## dablooz

How would I approach this method for a 4-way system?

My subs are the furthest drivers away from me (in the trunk). Then comes the midbasses in the back seat quarter panels, midranges in the front doors, and tweeters in the sail panels.

In the original post, it says there should be overlap between the two drivers being time aligned...

So, let's say I want to align my midranges with my midbasses. Currently, I run my midbasses from 80 Hz - 160 Hz, and my midranges from 160 Hz - 1.5 kHz. So when doing the time alignment, would I change the crossover on my midranges to be 150 Hz - 1.5 kHz? Is that what you mean by overlap?


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## derickveliz

dablooz said:


> Then comes the midbasses in the back seat quarter panels, midranges in the front doors, and tweeters in the sail panels.


*dablooz*, I'm not an expert here but I've been there and I've been learning from my mistakes and experimenting with different options, 
and to my believe the way you have your drivers *may be very difficult to bring the stage forward*, 
may I suggest relocating the *midbass to the doors, mids to the kick area or a-pillars...?*


*Where in NE are you?* we have a Northeast Spring Meet Saturday May 26th at 1 P.M.

Here are more details LINK

*My system is not a professional install, I have never been in a competition,* but at least you would get an idea of how every thing works and sounds.

Here is my Build LINK 2



*These numbers are OLD don't pay attention to them,* but just to get an idea of the location of my speakers to accomplish a good stage.









.


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## fcarpio

dablooz said:


> How would I approach this method for a 4-way system?
> 
> My subs are the furthest drivers away from me (in the trunk). Then comes the midbasses in the back seat quarter panels, midranges in the front doors, and tweeters in the sail panels.
> 
> In the original post, it says there should be overlap between the two drivers being time aligned...
> 
> So, let's say I want to align my midranges with my midbasses. Currently, I run my midbasses from 80 Hz - 160 Hz, and my midranges from 160 Hz - 1.5 kHz. So when doing the time alignment, would I change the crossover on my midranges to be 150 Hz - 1.5 kHz? Is that what you mean by overlap?


Tricky. You want to position yourself between the drivers you are aligning. You would have to start with a sub and a mid range, then do the mid bass with respect to the mid range and so on.

By overlapping I mean that you would have to set the crossover frequencies to the same range on the two drivers you are aligning. In your example you would set your sub to say 100Hz to 300Hz and the same range for your mid bass. The tricky part is that in your case you would have to overlap the frequencies from the sub and mid range, which is probably not too healthy for your system. 

EDIT: You can start with the mid bass and move your way up the frequency range and leave the subs for last. Then align your subs with respect to the rest of the (already aligned) system using either you delay or the phase knob if you have one. For this I am under the assumption that your subs are mono. I know for a fact that you can do it that way as well.


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## dablooz

fcarpio said:


> EDIT: You can start with the mid bass and move your way up the frequency range and leave the subs for last. Then align your subs with respect to the rest of the (already aligned) system using either you delay or the phase knob if you have one. For this I am under the assumption that your subs are mono. I know for a fact that you can do it that way as well.


This way sounds much easier. I will start with the midbasses.


Let's see if I understand it all correctly (please make corrections if neccessary):


Align the midranges in respect to the midbasses:

- Set the crossovers for BOTH the midbasses and midranges to play from, say 80 Hz - 250 Hz (bandpassed)
- Mute the left midbass (just the right side midbass is playing)
- Unmute and switch phase on the left midrange
- Adjust time delay on left midrange until it sounds thin/weak
- Bring left midrange back in phase
- Revert crossovers to original settings for BOTH the midbasses and midranges
- Unmute and switch phase on the right midrange
- Adjust time delay on the right midrange until it sounds thin/weak
- Bring right midrange back in phase. Now both midranges are perfectly aligned.

Now to align the tweeters in respect to the midranges:

- Set the crossovers for BOTH the tweeters and midranges to play from, say 1 kHz and above
- Mute the left midrange (just the right side midrange is playing)
- Unmute and switch phase on the left tweeter
- Adjust time delay on left tweeter until it sounds thin/weak
- Bring left tweeter back in phase
- Revert crossovers to original settings for BOTH the midranges and tweeters
- Unmute and switch phase on the right tweeter
- Adjust time delay on the right tweeter until it sounds thin/weak
- Bring right tweeter back in phase. Now both tweeters are perfectly aligned.

Now to do the subs:

I assume when aligning the subs last I don't have to change the phase or the crossover for them? So all I would have to do is simply unmute all of the drivers and adjust the time alignment on the subs until it sounds good, correct?


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## hilander999

dablooz said:


> Now to align the tweeters in respect to the midranges:
> 
> - Set the crossovers for BOTH the *tweeters* and midranges *to play from, say 1 kHz and above*
> - Mute the left midrange (just the right side midrange is playing)
> - Unmute and switch phase on the left tweeter
> - Adjust time delay on left tweeter until it sounds thin/weak
> - Bring left tweeter back in phase
> - Revert crossovers to original settings for BOTH the midranges and tweeters
> - Unmute and switch phase on the right tweeter
> - Adjust time delay on the right tweeter until it sounds thin/weak
> - Bring right tweeter back in phase. Now both tweeters are perfectly aligned.


*Be carefull not to blow your tweeters....*
Some if not most tweeters are not designed to play anywhere near that low, and you could fry them almost instantly with a test tone.

Somewhere around 3K would be a lot safer.
Check your speakers datasheet for usable frequency ranges.
Tweeters can be expensive to replace, depending on what they are.


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## subwoofery

Yep... A Focal tweeter will fry in secs having an FS close to 2kHz... 

Kelvin


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## fcarpio

dablooz said:


> This way sounds much easier. I will start with the midbasses.
> 
> 
> Let's see if I understand it all correctly (please make corrections if neccessary):
> 
> 
> Align the midranges in respect to the midbasses:
> 
> - Set the crossovers for BOTH the midbasses and midranges to play from, say 80 Hz - 250 Hz (bandpassed)
> - Mute the left midbass (just the right side midbass is playing)
> - Unmute and switch phase on the left midrange
> - Adjust time delay on left midrange until it sounds thin/weak
> - Bring left midrange back in phase
> - Revert crossovers to original settings for BOTH the midbasses and midranges
> - Unmute and switch phase on the right midrange
> - Adjust time delay on the right midrange until it sounds thin/weak
> - Bring right midrange back in phase. Now both midranges are perfectly aligned.
> 
> Now to align the tweeters in respect to the midranges:
> 
> - Set the crossovers for BOTH the tweeters and midranges to play from, say 1 kHz and above
> - Mute the left midrange (just the right side midrange is playing)
> - Unmute and switch phase on the left tweeter
> - Adjust time delay on left tweeter until it sounds thin/weak
> - Bring left tweeter back in phase
> - Revert crossovers to original settings for BOTH the midranges and tweeters
> - Unmute and switch phase on the right tweeter
> - Adjust time delay on the right tweeter until it sounds thin/weak
> - Bring right tweeter back in phase. Now both tweeters are perfectly aligned.
> 
> Now to do the subs:
> 
> I assume when aligning the subs last I don't have to change the phase or the crossover for them? So all I would have to do is simply unmute all of the drivers and adjust the time alignment on the subs until it sounds good, correct?


Yes, pretty much. But in your case I would start with both mid bass drivers and assigning your right mid bass as the reference point. In other words align the left mid bass with respect to the right mid bass. Alternatively, start by inverting the phase on the left mid bass and continue from there. Both options are really the same thing.


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## fcarpio

subwoofery said:


> Yep... A Focal tweeter will fry in secs having an FS close to 2kHz...
> 
> Kelvin


Yeah, good point. Read your speaker's spec sheet to see how far you can safely push them.


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## DAT

Nice write up... :thumbsup:


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## HCWLSU101

Crazy, tried this out and really couldn't hear the "thin spot" but I guessed. Turns out it sounded much better, but the strange thing is that my right midbass and tweeter are delayed more than the left side. Anyone ever seen this before?


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## hpilot2004

This methodology does work well, as some systems finding weak/thin areas may be harder to determine than others, my two way active front stage plus subwoofer was a straight forward process done with exceptional results. Thank you, Sir for your contribution to our hobby as DIY'ers!


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## skyven

Itreally worked for me with clean detail, in phase bass, vocal dan high, focus image with deep staging. 

Excelent


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## fcarpio

skyven said:


> Itreally worked for me with clean detail, in phase bass, vocal dan high, focus image with deep staging.
> 
> Excelent


Thanks for letting me know, glad it worked out for you.


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## fcarpio

Winno said:


> Have just used this method on a friend's car.
> His system is a full Morel 4 way with CDM88 mids and Piccolo tweeters in pillars, Elate 9s in the doors and an Ultimo 12 in the boot/trunk.
> I used mono pink noise because it was the only mono track we had.
> We also had to physically change some drivers' cables around to reverse the phase because the Clarion HX-D2 allows rev of phase between pass bands but not between left and right.
> 
> Results are superb in two areas;
> 1. Imaging and stage spread/width are significantly improved as you would expect.
> and a surprise by product;
> 2. The overall spectral balance has also improved significantly because of a lack of phase anomalies between each driver compared to previous tunes using other methodologies. The sound now has a smoothness about it that didn't exist previously. This is because the drivers are tuned to a reference which is the driver before it, which leads right back to the sub. We now have no rev phase set on any drivers in the system as all drivers are working together.
> I'm sure that if we RTA'd things, it would show a much smoother response across the entire 20 to 20.
> 
> Thank you for your post.
> Much appreciated indeed.
> 
> IMO, this thread is worthy of a 'sticky' permanently at the top of this forum.


So, did you ever RTA the system to see if there was an improvement?


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## Winno

Actually, we didn't. 
His car is stripped now to use as a trade in on a new vehicle but I'm just tuning my car now which uses the same technique with striking results. 
I hope to RTA that car very soon.


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## BowDown

Interesting. Just for ****s and giggles I'll start with a fresh preset and give this a shot today.


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## BowDown

fcarpio, I want to shake your hand.

This by far was the easiest way to setup TA. I have 8 speakers in my car (5-way setup; tweet, midrange, midbass, dash sub, rear sub) and once I got through all the fumbling of balance, fade, turn sub on/off, lap crossover points, and flip phase during testing.. I ended up with the best center stage, and overall sound I have heard! Wow, it just added a bit of effortlessness to the stage. Everything is cleaner and more defined!

Awesome! Well worth the 45minutes invested!

If I can do it with 8 speakers, I'm sure others can do it quicker.

I'm stoked now! Can't wait for 4PM so I can drive my car home. :laugh:


BTW: I had decent results using pink noise and doppler effect.. but this method is much easier with better results.

I used Foobar2000's DSP MONO down-sample plugin to convert to mono.


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## fcarpio

BowDown said:


> fcarpio, I want to shake your hand.
> 
> This by far was the easiest way to setup TA. I have 8 speakers in my car (5-way setup; tweet, midrange, midbass, dash sub, rear sub) and once I got through all the fumbling of balance, fade, turn sub on/off, lap crossover points, and flip phase during testing.. I ended up with the best center stage, and overall sound I have heard! Wow, it just added a bit of effortlessness to the stage. Everything is cleaner and more defined!
> 
> Awesome! Well worth the 45minutes invested!
> 
> If I can do it with 8 speakers, I'm sure others can do it quicker.
> 
> I'm stoked now! Can't wait for 4PM so I can drive my car home. :laugh:
> 
> 
> BTW: I had decent results using pink noise and doppler effect.. but this method is much easier with better results.
> 
> I used Foobar2000's DSP MONO down-sample plugin to convert to mono.


Great! This seems to be working well for a lot of people and that makes me happy.


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## fcarpio

Just a thought for the mono signal source. A $2 Y splitter will do the trick.


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## BowDown

Y adapter would work if someone was running an analog hu into a processor. Other than that it Prbly would work out.  



Posted from my Samsung Galaxy S III 32gb via tapatalk 2.


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## thehatedguy

I might be not understanding, but how would you do this line by line for a 3 way plus sub?


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## fcarpio

BowDown said:


> Y adapter would work if someone was running an analog hu into a processor. Other than that it Prbly would work out.
> 
> 
> 
> Posted from my Samsung Galaxy S III 32gb via tapatalk 2.


You would do it just before the amps.


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## fcarpio

thehatedguy said:


> I might be not understanding, but how would you do this line by line for a 3 way plus sub?


That is what I have and it worked fine. Can you please be more specific in your question? I am not sure I am understanding.


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## thehatedguy

Just an outlined step by step guide. When to mute. What to listen with, etc. Have a 7 week old that gets his nights and days mixed up...and I get night duty so my focus wanders sometimes.


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## fcarpio

How is this?


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## hpilot2004

So by your meaning of reference speaker, your time alignment on that speaker will be at zero, correct?


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## fcarpio

Yes, zero will work.

In theory, zero or whatever you want will work. You are aligning with respect to it. Zero makes things less complicated so go with that. Some processors don't have the option to set a zero point of reference, like some Pioneers. They use a different scale/reference.


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## thehatedguy

Any particular reason why you started with the sub and midbass?


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## BowDown

Usually when time aligning drivers you want to start with the furthest and next furthest. So in my case it was: 

rear sub and right mid bass
right mid bass to left mid bass
rear sub to front sub
right Mid bass to right midrange
Right midrange to left midrange
Right midrange to right tweeter
Right tweeter to left tweeter



Posted from my Samsung Galaxy S III 32gb via tapatalk 2.


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## quality_sound

Hoe. Lee. ****. 

I've been tuning for a long time and I've always thought I was pretty good at it but couldn't ever get it _just_ right. I did this just now and with NOTHING but XO and TA the image is completely locked in, doesn't wander, is tonally a lot better and less fatiguing, and damn near pinpoint with the accuracy. It's wild. I can't wait to see see what it looks like on the RTA now. I'm glad grabbed a "before" shot a few days ago.

Like you said, some of it was easier with music. I tried with pink noise then used music and really brought it into focus.

Thanks for the great write-up.


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## fcarpio

thehatedguy said:


> Any particular reason why you started with the sub and midbass?


I thought it was easier. If I start with the midbass I can tune theree speakers that are opposite to it.


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## fcarpio

BowDown said:


> Usually when time aligning drivers you want to start with the furthest and next furthest.


In my case I want to be BETWEEN the speakers I am tuning regardless of distance (distance is what I am fixing anyway, so it doesn't matter). This is in addition to the other conditions I mentioned earlier in this thread.


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## fcarpio

quality_sound said:


> Hoe. Lee. ****.
> 
> I've been tuning for a long time and I've always thought I was pretty good at it but couldn't ever get it _just_ right.


You were not that good then.  I am glad it worked out for you.


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## quality_sound

fcarpio said:


> You were not that good then.  I am glad it worked out for you.


That's why I said "thought".


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## fcarpio

Cruzer said:


> i thought the op said music was the best option as its dynamic and playing a wide spectrum?
> 
> i too struggled to hear it thinning, but my tweeter doesnt cross well to my mids. but i even had trouble with the mids and sub, sub playing up to 100hz and mids playing 80hz and up
> 
> i just took at as my ears not really trained for this stuff and guessed best i could


You want them both playing the same range, say 80-250Hz. This is not the same as the mid playing from 80-4Khz and the sub from 20-250Hz. Yes, they overlap but there is added noise you don't want for this.


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## Cruzer

fcarpio said:


> You want them both playing the same range, say 80-250Hz. This is not the same as the mid playing from 80-4Khz and the sub from 20-250Hz. Yes, they overlap but there is added noise you don't want for this.


I have a 2 way and I can cross my sub at 250hz but my mid I can only do 80-1.6k so there is going to be added noise no matter what unless maybe I use eq and cut everything other than 80-250

Just curious could u use an spl meter for this or would the spl level not change it just sounds thin and weak?


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## fcarpio

Cruzer said:


> I have a 2 way and I can cross my sub at 250hz but my mid I can only do 80-1.6k so there is going to be added noise no matter what unless maybe I use eq and cut everything other than 80-250
> 
> Just curious could u use an spl meter for this or would the spl level not change it just sounds thin and weak?


I think the EQ will help, just boost the wanted frequencies and cut the unwanted ones. I don't know about the SPL meter, in theory it should work but your ears will do the trick. Maybe some test tones in the desired frequency range (80-250) will help you better instead of music.

Here is a test tone generator you could try :http://www.esseraudio.com/en/test-t...l-sine-pink-noise-crest-factor/ttg-dl-en.html . I have not tried it but you could give it a shot.


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## xt577

This technique assumes that the sub is the furthest speaker, correct?

My sub is under the driver's seat, and my dash-mounted tweeters are both further from my ears than their respective woofers, so I suppose I would need to go about this whole process differently.

Starting with all of the speakers delayed the same amount, then going through all of the steps and decreasing the amount of delay (rather than increasing).


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## quality_sound

I'm sure you can do it with a mid as the starting point. I started with the sub even though my left mid is farther away. It worked fine.


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## BowDown

Well the main problem with starting with the left mid bass is it may be closer to you than another driver. Say you set the mid bass at 0. When adjusting the sub you will have trouble aligning them because the sub should be below 0. I guess it depends on your dsp. Many I have used takes the value and delays the signal that amount. Others seems to do some sort of subtraction from the lowest value and cluster fuxks the logic. I believe that's how pioneer does it? 



Posted from my Samsung Galaxy S III 32gb via tapatalk 2.


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## quality_sound

It'll still work. It did in my car.


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## BowDown

quality_sound said:


> It'll still work. It did in my car.


I don't see how it could. It may be close but I would be curious to see if you have the same numbers if you started with the furthest. Unless you didn't start with the mid bass on 0. If you start on 1 then there would be enough room to adjust. 



Posted from my Samsung Galaxy S III 32gb via tapatalk 2.


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## xt577

If the sub is closer than the woofer that it is being phase aligned with, and one is adding time delay to the woofer, the best result achievable would be an in-phase, but out of time alignment soundstage.


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## Bnixon

Subscribe


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## fcarpio

BowDown said:


> I don't see how it could. It may be close but I would be curious to see if you have the same numbers if you started with the furthest. Unless you didn't start with the mid bass on 0. If you start on 1 then there would be enough room to adjust.
> 
> Posted from my Samsung Galaxy S III 32gb via tapatalk 2.


Correct, you don't have to start as zero for your reference driver.


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## myhikingboots

sub'd


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## fcarpio

xt577 said:


> This technique assumes that the sub is the furthest speaker, correct?
> 
> My sub is under the driver's seat, and my dash-mounted tweeters are both further from my ears than their respective woofers, so I suppose I would need to go about this whole process differently.
> 
> Starting with all of the speakers delayed the same amount, then going through all of the steps and decreasing the amount of delay (rather than increasing).


Correct. Your reference speaker does not have to start as zero. It only has to be the reference by which you will time align the rest.


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## Hextall 27

Who else has done this with P01/P99RS? Does the delay go up as you increase distance on the L but then do some type of equalization when the R speaker is done? I thought Pioneer tried to do the math for you.


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## Mic10is

Hextall 27 said:


> Who else has done this with P01/P99RS? Does the delay go up as you increase distance on the L but then do some type of equalization when the R speaker is done? I thought Pioneer tried to do the math for you.


Pioneer is backwards. to delay the left you actually change settings for the right


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## Winno

I've been playing with a variation on this whole technique;
- Instead of mono pink noise, I've used mono pure sine burst tones (5 quick bursts on repeat) of various freqencies (played one at a time)
- I've kept all drivers in phase when setting the phase on a single driver. 

All other principles outlined by the OP were followed.

Why did I do it this way?
I find it easier to hear the attack or impulse of the drivers acting together to judge correct relative phase and placement of the sound smack in the middle between drivers. I also find it easier to hear something move into focus rather than listeneing for when it is least focused.

Now, my speakers just disappear. I look at the drivers but I could swear that no sound was coming from them. The placement of performers in the stage out in front of the car is palpable, the sound truely transparent.

A big thanks again goes to the OP for this idea.


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## Woosey

Mic10is said:


> Pioneer is backwards. to delay the left you actually change settings for the right


Or you can see it as max delayed, the bigger the distance less delay will be applied..


----------



## Woosey

xt577 said:


> This technique assumes that the sub is the furthest speaker, correct?
> 
> My sub is under the driver's seat, and my dash-mounted tweeters are both further from my ears than their respective woofers, so I suppose I would need to go about this whole process differently.
> 
> Starting with all of the speakers delayed the same amount, then going through all of the steps and decreasing the amount of delay (rather than increasing).


I recommend to get measuring with a mic in some kind of way... I just measured our demo-car and that car has the subs under the passengerseat.. with the high-pass on the sub 6dB @ 60Hz I had to delay the rest of the set approx. 5.5ms ( phase shift by a filter is also a delay! )

Read this: Phase angle calculation from time delay and frequency calculate phase lag difference time of arrival ITD phi phase shift - sengpielaudio


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## JVD240

I also use this technique but play tones within the overlapping frequency ranges.

For sub-mid I use ~150Hz tone. mid-tweet I use ~3.5kHz tone.

Does anyone foresee any issues with this? It seems much easier to identify the "weakest signal" doing it this way. I've got noob-ears though.

I use pink/white noise for level matching all of the drivers.


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## quality_sound

Woosey said:


> Or you can see it as max delayed, the bigger the distance less delay will be applied..


Exactly. You're inputting the distance between the listening position and the speaker, not the delay.


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## ADCS-1

Sub`d.  Tried this method a few days ago on a 9887, who the owner had set by music and hope. Wrote down his digits, erased the memory, get to work with pure mono test tones (100, 400, 4k and 6k). WOW.


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## Hoye0017

Woosey said:


> I recommend to get measuring with a mic in some kind of way... I just measured our demo-car and that car has the subs under the passengerseat.. with the high-pass on the sub 6dB @ 60Hz I had to delay the rest of the set approx. 5.5ms ( phase shift by a filter is also a delay! )
> 
> Read this: Phase angle calculation from time delay and frequency calculate phase lag difference time of arrival ITD phi phase shift - sengpielaudio


Good article posted there. Thank you. I think that helps define what I have understood to be true for some time but couldn't grasp why. For a long time I thought that electronic time alignment was simply a buffered delay of the entire channel's audio. Turns out, time alignment is really basically a frequency dependent phase shift. 

That's why I think it's a bit more complicated than the technique suggested here. For one, my understanding is that most electronic filters induce a phase shift just like passive crossovers do. Each different slope and crossover point will have a different effect on the phase and response of the drivers in that channel. If you change crossover settings to create some overlap, you are creating 2 problems:
1. The phase alignment you created by performing this alignment technique may be erased when you change your filter settings back to where they should be.

2. In the end,assuming #1 doesn't happen in your case, your alignment will really only be great for the frequencies in the overlap. As the time alignment is really frequency dependent, you may be short-changing the drivers alignment at the opposite ends of their frequency spectrums.

Don't get me wrong, I like the concept behind this, I just think this may be why the some are reporting hits and some are reporting misses with this technique. Not everyone is using the same system configuration, automobile, or DSP. 

I think the one main concept that doesn't translate between the guitar mic concept and this is the fact that the mics are full range devices with no active or passive processing between them and the mixer. Nevermind what happens when the recording is stereo and what happens in production before it even gets to your car.


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## fcarpio

Hoye0017 said:


> Good article posted there. Thank you. I think that helps define what I have understood to be true for some time but couldn't grasp why. For a long time I thought that electronic time alignment was simply a buffered delay of the entire channel's audio. Turns out, time alignment is really basically a frequency dependent phase shift.
> 
> That's why I think it's a bit more complicated than the technique suggested here. For one, my understanding is that most electronic filters induce a phase shift just like passive crossovers do. Each different slope and crossover point will have a different effect on the phase and response of the drivers in that channel. If you change crossover settings to create some overlap, you are creating 2 problems:
> 1. The phase alignment you created by performing this alignment technique may be erased when you change your filter settings back to where they should be.
> 
> 2. In the end,assuming #1 doesn't happen in your case, your alignment will really only be great for the frequencies in the overlap. As the time alignment is really frequency dependent, you may be short-changing the drivers alignment at the opposite ends of their frequency spectrums.
> 
> Don't get me wrong, I like the concept behind this, I just think this may be why the some are reporting hits and some are reporting misses with this technique. Not everyone is using the same system configuration, automobile, or DSP.
> 
> I think the one main concept that doesn't translate between the guitar mic concept and this is the fact that the mics are full range devices with no active or passive processing between them and the mixer. Nevermind what happens when the recording is stereo and what happens in production before it even gets to your car.


Interesting article but it refers to pure sinusoidal waves (like some test tones) and it clearly makes an exception of music which is not a pure sinusoidal wave. I did take the time to write to the article's author to see if I can get more information about how accurate this time aligning technique is and to see if s/he could chime in. An opinion from someone qualified would be refreshing. 

Anyway, I think we are splitting hairs and removing the joy of something that is supposed to be fun.


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## co_leonard

Here's a story I'd like to share: 

I heard of this guy who wanted to SEE the actual time-alignment delay from the RCA outputs of his head unit, an old Alpine CDA-9815.

On his computer, he created WAV files containing quarter-second pulses from sine-wave test tones recorded at -10dBFS. The pulses repeated every half-second for 60 seconds. No idea what software he used. Twenty-one sequential WAV files were created, starting at 100Hz going to 10kHz in one-third octave steps. Then the WAV files were all burned to a CD. 

To ensure a good reading, he put his head unit on a test-bench, powered by a fully-charged car battery. He set time alignment on all channels to zero. EQ set to "flat." Crossover on all channels set to "all-pass." Balance set to center, fader set to the middle. 

He owned a digital oscilloscope. Nothing fancy, just a portable Fluke unit. He then hooked up channel-1 of his scope to the left-front RCA output and channel-2 to the right-front RCA output. Then he played the CD starting with track-1, the 100Hz pulses. Volume set to "22" gave him roughly a 1-volt RMS output. 

Looking at his scope, pulses seen by channel-1 perfectly overlapped pulses seen by channel-2. He fully expected this. Then he played the next track, 125Hz. Same result on the scope. Then the next track and the next track until all 21 tracks were played. Same result on the scope, pulses seen by channel-1 perfectly overlapped pulses seen by channel-2. 

Now the interesting part. 

He used the head unit's time alignment feature to delay the left-front channel by one step. That's 0.1 millisecond on his Alpine. Then he played track-1 and carefully studied the scope. True enough, pulses from the left-front channel began exactly 0.1-millisecond after the pulses from the right-front channel. So he played the next track. And the next track. 

What he saw was that all pulses coming from the left-front channel were delayed by 0.1-millisecond compared to the right-front channel regardless of frequency.

Then he increased the delay to 0.2-milliseconds. He saw that all pulses coming from the left-front channel were now delayed by 0.2-millisecond again regardless of frequency.

Just to check, he delayed the RIGHT-front channel by 0.2-milliseconds and played all 21 tracks. He expected to see pulses on channel-1 perfectly overlapping pulses on channel-2, and this is exactly what the scope showed. 

He went all the way to a 5-millisecond difference then he called it a day. 

So he concluded, "no phase shifts happening here. The head unit really IS delaying the sound."

Just a story I heard, folks. Did all this actually happen? I haven't a clue. I'd like to believe it, though 

I would like to try this out on my own head unit, I just don't have the necessary gear. Hehe..

Happy new year!


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## Hoye0017

I suppose this could be easily tested by someone who knows their way around a nice oscilloscope. You could run two channels in to it and observe the waves as you change relative delay at different frequencies. It would show up as two waves at different phase angles. I wonder if you would need to run 2 different frequencies concurrently to observe the changes in each while the other is present. Then i guess you might need 2 oscopes to get a good look at each waveform. Then we'd want to try different dsp's to see what each one does. I get the purpose of the pulses, I just think it would still be ok to show up as a phase shift as long as its consistent for all frequencies to disprove the frequency dependence concept.

On second thought, Forget about all that, this is starting to sound like homework and that's why I dropped out of 3rd grade.


----------



## fcarpio

Hoye0017 said:


> I suppose this could be easily tested by someone who knows their way around a nice oscilloscope. You could run two channels in to it and observe the waves as you change relative delay at different frequencies. It would show up as two waves at different phase angles. I wonder if you would need to run 2 different frequencies concurrently to observe the changes in each while the other is present. Then i guess you might need 2 oscopes to get a good look at each waveform. Then we'd want to try different dsp's to see what each one does. I get the purpose of the pulses, I just think it would still be ok to show up as a phase shift as long as its consistent for all frequencies to disprove the frequency dependence concept.
> 
> On second thought, Forget about all that, this is starting to sound like homework and that's why I dropped out of 3rd grade.


I hear ya. Read the post right before your last post, someone may have already done it.


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## Hoye0017

that's the post I was referencing. I understand the concepts, including the pulses. 

the only problem is that he's saying that he only heard that someone did this test but he has no way to verify. Also the test was only one frequency at a time on one piece of equipment on a basic scope. 

I hope that those findings are true. I also use Alpine's internal time alignment and have been able to successfully tune by ear in multiple setups. If this is true, that might explain why I've obtained better results than I expected.


----------



## co_leonard

Hoye0017 said:


> I also use Alpine's internal time alignment and have been able to successfully tune by ear in multiple setups. If this is true, that might explain why I've obtained better results than I expected.


And this is why our hobby gives us so much fun!


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## Woosey

fcarpio said:


> Interesting article but it refers to pure sinusoidal waves (like some test tones) and it clearly makes an exception of music which is not a pure sinusoidal wave. I did take the time to write to the article's author to see if I can get more information about how accurate this time aligning technique is and to see if s/he could chime in. An opinion from someone qualified would be refreshing.
> 
> Anyway, I think we are splitting hairs and removing the joy of something that is supposed to be fun.


Got any response?


----------



## fcarpio

Woosey said:


> Got any response?


Unfortunately no answer.


----------



## co_leonard

co_leonard said:


> Here's a story I'd like to share:
> 
> I heard of this guy who wanted to SEE the actual time-alignment delay from the RCA outputs of his head unit, an old Alpine CDA-9815.
> 
> On his computer, he created WAV files containing quarter-second pulses from sine-wave test tones recorded at -10dBFS. The pulses repeated every half-second for 60 seconds. No idea what software he used. Twenty-one sequential WAV files were created, starting at 100Hz going to 10kHz in one-third octave steps. Then the WAV files were all burned to a CD.
> 
> To ensure a good reading, he put his head unit on a test-bench, powered by a fully-charged car battery. He set time alignment on all channels to zero. EQ set to "flat." Crossover on all channels set to "all-pass." Balance set to center, fader set to the middle.
> 
> He owned a digital oscilloscope. Nothing fancy, just a portable Fluke unit. He then hooked up channel-1 of his scope to the left-front RCA output and channel-2 to the right-front RCA output. Then he played the CD starting with track-1, the 100Hz pulses. Volume set to "22" gave him roughly a 1-volt RMS output.
> 
> Looking at his scope, pulses seen by channel-1 perfectly overlapped pulses seen by channel-2. He fully expected this. Then he played the next track, 125Hz. Same result on the scope. Then the next track and the next track until all 21 tracks were played. Same result on the scope, pulses seen by channel-1 perfectly overlapped pulses seen by channel-2.
> 
> Now the interesting part.
> 
> He used the head unit's time alignment feature to delay the left-front channel by one step. That's 0.1 millisecond on his Alpine. Then he played track-1 and carefully studied the scope. True enough, pulses from the left-front channel began exactly 0.1-millisecond after the pulses from the right-front channel. So he played the next track. And the next track.
> 
> What he saw was that all pulses coming from the left-front channel were delayed by 0.1-millisecond compared to the right-front channel regardless of frequency.
> 
> Then he increased the delay to 0.2-milliseconds. He saw that all pulses coming from the left-front channel were now delayed by 0.2-millisecond again regardless of frequency.
> 
> Just to check, he delayed the RIGHT-front channel by 0.2-milliseconds and played all 21 tracks. He expected to see pulses on channel-1 perfectly overlapping pulses on channel-2, and this is exactly what the scope showed.
> 
> He went all the way to a 5-millisecond difference then he called it a day.
> 
> So he concluded, "no phase shifts happening here. The head unit really IS delaying the sound."
> 
> Just a story I heard, folks. Did all this actually happen? I haven't a clue. I'd like to believe it, though
> 
> I would like to try this out on my own head unit, I just don't have the necessary gear. Hehe..
> 
> Happy new year!


Couple of days ago, I watched someone do this with is iPad. Software was "SignalScope Pro" from Faber Acoustical, LLC.

He had a special Dock Connector that had both USB and audio I/O. He plugged in a USB mic (Samson C01U) to the Dock Connector. Then he plugged its audio-output to the aux-in of his head unit (Pioneer DEX-P99RS). Yes, the Samson C01U works with his third-gen iPad. No, it does not shut off. Yes, its response isn't flat but that's OK - we're not measuring frequency response. 

He then used SignalScope to play "POLARITY CHECK" pulses. 

NOTE: No idea what these pulses are made of, but you could clearly hear it from all speakers - from the subwoofer to the tweeter and everything in between.

Now to check one driver only. Use a camera tripod to position USB microphone in the center of the driver's seat headrest but floating 2 inches in front of it. Use the P99 remote to mute all speakers except the left tweeter. 

Use the USB mic to listen to Polarity Check pulses and display them on the oscilloscope. The app has auto-trigger so that the scope display clearly shows each pulse heard by the USB mic. Then drag and pinch the display to better show the "distance" (time delay) between each pulse. This freezes the current X-Y grid.

Now use time alignment to delay the signal. 

Because the display's X-Y grid has already been frozen, it is easy to see the effect of the head unit's time alignment. Polarity-check pulses really do begin a bit later, depending on the T/A setting. 

His test shows that at least on the Pioneer DEX-P99RS, time alignment works consistently. A delay of X centimeters on the head unit results in an equal delay of X milliseconds displayed on the iPad scope.

Then mute that driver and go to another driver until all drivers have been checked. Sure enough, a delay of X centimeters on that driver will result in an equal delay of X milliseconds displayed on the iPad scope.

With these results, I suppose stage 1 of the experiment is successful. 

Now Stage 2 which involves a PAIR of drivers, such as both left and right tweeters. Set time alignment to ZERO on the P99 and play the same Polarity-Check Pulses through both tweeters. Then adjust T/A on the left tweeter by one step (0.77cm). The iPad scope showed a 22-microsecond (0.022 millisecond) delay as compared to the right tweeter which showed no delay. 

And YES, the engine was off and the A/C was off. The guy with the iPad was sitting in the back seat. 

With these results, I suppose stage 2 of the experiment is also successful.


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## Woosey

fcarpio said:


> Unfortunately no answer.


Too bad


----------



## cyberdraven

co_leonard said:


> Couple of days ago, I watched someone do this with is iPad. Software was "SignalScope Pro" from Faber Acoustical, LLC.
> 
> He had a special Dock Connector that had both USB and audio I/O. He plugged in a USB mic (Samson C01U) to the Dock Connector. Then he plugged its audio-output to the aux-in of his head unit (Pioneer DEX-P99RS). Yes, the Samson C01U works with his third-gen iPad. No, it does not shut off. Yes, its response isn't flat but that's OK - we're not measuring frequency response.
> 
> He then used SignalScope to play "POLARITY CHECK" pulses.
> 
> NOTE: No idea what these pulses are made of, but you could clearly hear it from all speakers - from the subwoofer to the tweeter and everything in between.
> 
> Now to check one driver only. Use a camera tripod to position USB microphone in the center of the driver's seat headrest but floating 2 inches in front of it. Use the P99 remote to mute all speakers except the left tweeter.
> 
> Use the USB mic to listen to Polarity Check pulses and display them on the oscilloscope. The app has auto-trigger so that the scope display clearly shows each pulse heard by the USB mic. Then drag and pinch the display to better show the "distance" (time delay) between each pulse. This freezes the current X-Y grid.
> 
> Now use time alignment to delay the signal.
> 
> Because the display's X-Y grid has already been frozen, it is easy to see the effect of the head unit's time alignment. Polarity-check pulses really do begin a bit later, depending on the T/A setting.
> 
> His test shows that at least on the Pioneer DEX-P99RS, time alignment works consistently. A delay of X centimeters on the head unit results in an equal delay of X milliseconds displayed on the iPad scope.
> 
> Then mute that driver and go to another driver until all drivers have been checked. Sure enough, a delay of X centimeters on that driver will result in an equal delay of X milliseconds displayed on the iPad scope.
> 
> With these results, I suppose stage 1 of the experiment is successful.
> 
> Now Stage 2 which involves a PAIR of drivers, such as both left and right tweeters. Set time alignment to ZERO on the P99 and play the same Polarity-Check Pulses through both tweeters. Then adjust T/A on the left tweeter by one step (0.77cm). The iPad scope showed a 22-microsecond (0.022 millisecond) delay as compared to the right tweeter which showed no delay.
> 
> And YES, the engine was off and the A/C was off. The guy with the iPad was sitting in the back seat.
> 
> With these results, I suppose stage 2 of the experiment is also successful.


Hi Elco, would it be correct to say that the correct TA is the point wherein all the phase of the speakers are dead-set acoustically? As I thought, phase is relative to distance. So if your nearer into one speaker, the phase of the two speakers is not in sync. Just a hunch, that a correct TA would be the point wherein you have the correct phase as well. I would relate it on normal tweeter experiments, without changing TA, once you reverse a polarity of one tweeter, the soundstage moves drastically to the right. Given your experiment, when is the point of your final TA measurement yeilds a completely sync scope reading between the two tweeters?

Thanks

Paeng


----------



## sqnut

........and if at the end of all that measuring and correcting, your ears repeatedly tell you it needs tweaking.........did you measure wrong or is the measurement incorrect / incomplete?

Once set, is it cast in stone or will you use it as a tuning tool. Less used but something to play with for getting something dialed in better at a slight and acceptable cost elsewhere. Yes, there will be a base setting for each car and from there you can play around a bit in a very small band.

Assume at a given setting the drivers are in acoustic phase, now if you add equal delay to all drivers, the drivers are still in relative phase but the sound starts changing, keep going and your sound will eventually fall in place again. The two 'in place' will also sound different. 

Just curious to hear how it is for everyone else.


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## BowDown

sqnut said:


> Just curious to hear how it is for everyone else.


Possibly truth to this.. I remember when I was getting ready to integrate my rear sub I pushed all values up 2ms to make room for the added delay. I could of sworn it sounded a bit different.. but figured it was all in my head. :lol:


----------



## Dillyyo

fcarpio said:


> Unfortunately no answer.


Kudos, Fcarpio!!! A lot of positive feed back in this thread. I can't wait to get my system back into the G so that i can try this. TA in the G had always left me wanting better, but i know if you pulled it off in yours, with this method, then I should be in for a big grin when I'm back up and running! :beerchug:

How is this not a sticky yet?


----------



## Woosey

BowDown said:


> Possibly truth to this.. I remember when I was getting ready to integrate my rear sub I pushed all values up 2ms to make room for the added delay. I could of sworn it sounded a bit different.. but figured it was all in my head. :lol:


This can be possible, a change in pitch since you are slowing the signal down of speeding it up for a little bit...

My dreambox has a delay on the hdmi ( delay between audio and video ), if this is adjusted this is audible too...


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## quality_sound

If you adjust the delay of ALL speakers then you haven't really done anything. Phase and TA are relative.


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## fcarpio

Dillyyo said:


> Kudos, Fcarpio!!! A lot of positive feed back in this thread. I can't wait to get my system back into the G so that i can try this. TA in the G had always left me wanting better, but i know if you pulled it off in yours, with this method, then I should be in for a big grin when I'm back up and running! :beerchug:
> 
> How is this not a sticky yet?


Thanks man, glad to hear you still have the G. I plan on keeping mine for a while longer.


----------



## fcarpio

quality_sound said:


> If you adjust the delay of ALL speakers then you haven't really done anything. Phase and TA are relative.


This.


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## Dillyyo

fcarpio said:


> Thanks man, glad to hear you still have the G. I plan on keeping mine for a while longer.


Actually, the original one got totaled about 3 months before my last payment and 148K with no major issues up to that point. Really sucked because I was looking foward to starting to modify it with FIa and other performance components. Ended you taking the ins check and purchasing a pre-cert black coupe (original color i wanted but didn't get) with 22K miles, out of Orlando. 

I'm going to be having my system installed this weekend and then I will be driving down to Orlando/Boynton Beach area in the third week of March. Maybe I can hit you up and listen to your car finally and you can help me with this technique if I run into any issues on my own. 

Let me know....


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## fcarpio

Sure, just reply to this thread when ready as I do not get email notifications from PM's. Unfortunately my system is not 100% right now but I intend to fix it soon.


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## Benja

I have tried to read everything in this thread but am left confused.

It is my understanding that TA is merely a variable delay set in each channel.

How does an EQ affect TA? An EQ is a variable attenuator over a given span. How and why would it affect phase? Unless I missed it, I don't understand.


----------



## fcarpio

Benja said:


> I have tried to read everything in this thread but am left confused.
> 
> It is my understanding that TA is merely a variable delay set in each channel.
> 
> How does an EQ affect TA? An EQ is a variable attenuator over a given span. How and why would it affect phase? Unless I missed it, I don't understand.



For now I would only focus on the first post on this thread. Get that done first so you can focus on something else later, or do this later.


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## Fast Hot Rod

Benja said:


> How does an EQ affect TA? An EQ is a variable attenuator over a given span. How and why would it affect phase? Unless I missed it, I don't understand.


To understand it, you'll have to understand the phase relationship between voltage and current, then how it applies to RCL/RLC circuits.

R = Resistive
C = Capacitive
L = Inductive

For a purely resistive circuit, voltage and current are in phase. Their waveforms basically sit on top of each other, like so:










You can see that both waveforms start at zero degrees, extend to their positive peak at 90 degrees, back to zero at 180 degrees, down to their negative peak at 270 degrees, then back to zero at 360 degrees. (Zero degrees again.) This process repeats through another 360 degrees to 720 degrees. With me so far?

The reason this is important is because when you introduce a capacitor or an inductor into a circuit, it causes a phase shift between voltage and current. A nice way to remember it is: ELI the ICEman.

Where E = Voltage, I = Current, L = Inductor, and C = Capacitor.

ELI = Voltage leads Current in an Inductive load
ICE = Current leads Voltage in a Capacitive load

So for Inductive circuits:










...and Capacitive circuits:










As you start to combine capacitors and inductors into circuits, you start to see these phase shifts between the voltage and current. If you have ever looked at a 1st order crossover (a simple cap in series with a tweeter, or a coil in series with a woofer) then you have probably heard that they have a 90 degree phase shift. 










A 2nd order crossover has a 180 degree phase shift, but it has a capacitor and an inductor for both drivers. (Which is why the tweeter leads are reversed in relation to the woofer.) 










There is a lot that goes into the math behind it all, but the basic premise is that the circuit response is dependent on the value of the circuit resistance, capacitance, inductance, and frequency. This is where you start getting into capacitive reactance and inductive reactance, and the overall circuit reactance. 

The thing is, an EQ is essentially a set of filters designed with capacitors and/or inductors that allow you to boost or cut a particular frequency. In doing so, they are also going to introduce phase shift into the circuit by nature of their design. 

Realize that I am just scratching the surface on this subject... there's a lot more that goes into it than my simplistic explanation here. But if you're interested in learning more about it, this should point you in the right direction.


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## Woosey

fcarpio said:


> This.


Nope, but the moment you are delaying ( actually changing the setting ) it does on my set here.. as soon as you let go of the buttons it's normal...


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## Benja

Thanks Hot Rod. 

There has got to be a better way. lol

DSPs, can't they accomplish amplification and attenuation without shifting the phases? If not now, in the future?

It seems that eq's just shift phase to get a reduction in db, which to me sounds like a lazy way to decrease db. Just MHO and probably wrong.


----------



## Dillyyo

fcarpio said:


> Now you are going to do the same thing with the left mid, you are going to time align the left mid with respect to the right mid. The only time alignment you are doing at this point is to the left mid only as the right mid is already aligned with the subs. You are going to set the left mid out of phase and start increasing the time and listen for the signal to start to cancel and to sound weak, thin and unfocused. Find the worst sound and that is where you want to be. Now the fun part, bring the left mid back in phase and you will immediately hear the sound JUMP in front of you. That is because your two mids are PERFECTLY time aligned.
> 
> *Now you are going to mute your right mid and unmute your left tweeter. What you want to try to do is to time align speaker that are opposite to each other (one left and one right)* and try to have their frequencies overlap a bit but safely. If you have your crossover set to not overlap you will not be able to align a mid with respect to a sub, nor you will be able to align a tweeter with respect to a mid. If there is no frequency overlap there will be little or no cancellation to listen for when out of phase. Just repeat the process until you are done.
> 
> I hope this helps and please post your comments with the results you get.


I am assuming this is a typo because it is contradictory. Also, later in this thread you provide diagrams on the process, but seem to use the left MB as the ref for the sub, right MB and right MR. Yet, in this post you seem to intend (if truly is a typo) to try and zig zag from rear to front. In theory it seems that as long as one speaker stays at reference 0, then the exact manner in which you actually perform these steps is only limited by frequency over lap capabilities of the drivers and optimal positioning to most easily discern the sought after indicator. Is this an accurate position? 

I'm going to try this on my install at the end of today and just want to make sure it goes flawless. My "main alignment" reference driver will likely be the passenger side MB, since I'm pretty sure it's furthest and all I need to do is add delay to all other speakers. But, I question why I can't just use the sub as ref since the "testing" reference driver would move as you proceed up through your other drivers. I'm going to try and go zig zag from rear IB subs to tweeters up front and use the last aligned driver as the "testing" reference. 

Is my understanding of this correct or am I out in left field?! :laugh:


----------



## therapture

It seems this would work:

Since the sub (in my car) is furthest, it's the reference. The passenger speaker is the next in line, with the driver speaker being the closest.


1. Set mid HP to 40hz and sub LP to 150+ or more...
2. Turn off/mute left mid.
3. TA the right speaker and sub, with pink noise and tones until smoothest response is heard. I definitely could hear the background "warble" increase and decrease as I moved TA back and forth on the mid, I settled on the smoother/least amount of warble and the lowest pitch. It took a bit to realize what I was looking for.
4. Now, mute the right mid.
5. TA the left mid and sub together just like in step 2.
6. Turn off the sub and check TA between the two mids, adjust as needed.
7. Turn everything on, and check for image and balance.

I did it that way, then used pink noise tracks to verify alignment, and tweaked EQ to get the frequency ranges "in vertical line" in the middle of dash.

Then I used a ****load of different music to tweak further, lots of vocal stuff like Nora Jones, Beth Hart, Diana Krall...that gets my upper ranges of EQ dialed in.

Then I got into my psytrance, IDM, etc., that has boatloads of midbass, and dialed in the low end until things centered up and sub and midbass integrated better. Had a big "WTF-I'M AN IDIOT" moment as I discovered my sub phase was whack, a simple swap of wires at the amp got me a huge, huge improvement in integration. The entire bass "presence" moved to the dash.

The first 7 steps got me close...the remaining things got me better, as I progressed, the EQ changes were tiny, and the TA increments got very small, until I was manually entering in .05 increments.

For an SQ and DSP noob, I am very, very happy with my sound at this point.


----------



## dwhite832003

I'll admit to only reading through 3 pages of this thread but is it possible to use a specific frequency with the over lapping bands? 
*Example*
Mids down to 60
Woofers up to 80
Use 70 test tone?...


----------



## Woosey

dwhite832003 said:


> I'll admit to only reading through 3 pages of this thread but is it possible to use a specific frequency with the over lapping bands?
> *Example*
> Mids down to 60
> Woofers up to 80
> Use 70 test tone?...


Sort of, the only problem is the shift that comes with setting the XO back to the normal listening position... ( mids back to 80/100 whatever )

I really don't think overlap is needed because the crossoverfrequency is @-3db so it's only 3db under the rest ( theoretical ) this means the Null should be audible to without overlap.. 

In practice there are more things to keep in mind... first of all: level setting


----------



## dwhite832003

I got cha 
I was just thinking that if the frequency was sum what isolated from the rest of the spectrum it would be easier to detect the consolation!


----------



## redavalanche

Assuming you guys have head units with built in processing? Sort of like my home theater receiver. Sorry but my knowledge is from the eighties. And the crossover points are changed at a dedicated crossover or amp?

My home receiver has Audyssey. So new head units have time delay which can be set manually? But they are not capable of measuring and setting time delay or cabin correction on there own? yet...


----------



## JVD240

redavalanche said:


> Assuming you guys have head units with built in processing? Sort of like my home theater receiver. Sorry but my knowledge is from the eighties. And the crossover points are changed at a dedicated crossover or amp?
> 
> My home receiver has Audyssey. So new head units have time delay which can be set manually? But they are not capable of measuring and setting time delay or cabin correction on there own? yet...


Yes, a select few head units have adjustable time delay(time alignment) and user select-able crossovers.(frequency, slope, phase, etc.) It is also common for these to have an auto tune option.(time alignment, crossovers, EQ) Some even come with the mic for tuning.

Most amps now have adjustable crossovers although they are not as flexible as the head units or dedicated DSP. Some amps even have DSP(computer controlled) built in.

When you hear people use the term "active" they are talking about using no passive crossovers. All of those settings are done in the radio, dedicated DSP or the amps themselves. Running active requires more amplifier channels, however.


----------



## redavalanche

Thanks for the reply, that explains quite a bit.


----------



## fcarpio

Just tried this method with my new processor (bit ten) and it worked out beautifully, I am very happy with the results.


----------



## ecbmxer

I'm gonna give this a shot in the next few days. Seems like a lot of people have been having good success with the method!


----------



## peekeesh

Tried this method and it worked. Thanks OP!


----------



## fcarpio

I just realized I can make the T/A even tighter by adjusting the levels, kind of like a balance adjustment. This song is so focused in my system that Thelma Houston may as well be in my car. 

To Know You is to Love You - Thelma Houston & Pressure Cooker - YouTube

Try it!


----------



## jbholsters

This is exactly how we set the delays in my car in the early 90's with an Alpine 3681. Anyway one of the other installers at our shop, did sound for a bunch of bands and he thought of this same thing. Works great with horns too guys.

What the hell kind of cars are you driving where the sub is the furthest speaker? I guess your subs aren't against the front wall of your trunks.


----------



## fcarpio

jbholsters said:


> What the hell kind of cars are you driving where the sub is the furthest speaker? I guess your subs aren't against the front wall of your trunks.


----------



## jbholsters

wow, is there enough delay on your DSP for that


----------



## jbholsters

Something to consider that hasn't been mentioned, or I overlooked reading it.
If your image isn't dead center after these adjustments, you have to redo everything in like groups after delaying everything on one side to center the image (minus sub). So play both mids together in mono overlapped with sub and so forth and readjust. Then move up the line to the next highest frequency drivers etc....

You could also adjust levels on one side to compensate, but the image might wander a little.

If you have truerta or something similar, you can increase the resolution, and narrow the high and low spl level on the screen to just show the overlap frequencies and delay until those frequencies hit there lowest point, then flip back inphase and move on. Using the RTA is more accurate. All this is doing is aligning phase of one speaker to the next. You really wouldn't need to do anything to your x-over points if using the rta. You could also just use a sign wave at the x-over frequency, which is already mono. If you have a pre-amp for your RTA, you can feed into an aux channel on your dsp and use the rta program generator to feed the test tones.


----------



## Jericho941

I spent the afternoon trying this out. I'm using an alpine w900bt with the h100 processor. The process was a little tedious as my amps are the alpine pdx and must have the individual speaker plugs pulled before you can reverse polarity.

I have a 4" component set mounted in the dash pointing up into the windshield on a passive crossover, and a 6x9 woofer mounted in each door for a active/passive three way plus sub system. For a control in this experiment, the alpine allows several pre-set saves for your processor settings.

I started a new pre-set and went through the process of trying to set the TA.

I had a playlist set up on my iPod with pink noise and test tones in various frequencies and some other tools. I started with pink noise, but I wasn't able to identify the changes well enough. I then synced the sub and mid bass with a 100hz test tone and a RTA app on my android phone (phone's mic) and watched as the tone's level go up and down. When I got the most cancelation I set that as my final setting. I moved on to the other midbass and then did the dash tweeter/woofer sets (mounted right next to each other so TA together). I used both 500 and 3.2k hz tones and pink noise to match the midbass and the component set.

My first big surprise is that there was something wrong with my processor's menu and the front and rear TA are switched, while L/R balance and the crossover menu are correct. I ran the TA all of the way up on the first mid bass with no change at all as the menu was wrong. I tried the "front" that should have been linked to the tweeters and suddenly it began to work!

It's no wonder I was having such problems with TA as my "front/rear" settings were BACKWARDS!

The second surprise is that the ammount of delay for my experiment was very high. My subs are mounted as far back in the trunk as possible, facing forward as I read somewhere that that was more ideal for larger cars with trunks, and they are more than 5' from my headrest.

Separately I also followed the Alpine recommended TA set up procedure from my HU manual.

The final results of the Inverse Phase time alignment method were very good. I finally had a center image and vocals directly in front. I compared to my previous totally wrong set up and the difference was significant. I also compared to the Alpine process and it's ten minutes of required maths and the Inverse method still sounded best.

I don't know if my methods were even correct, but I'm happy with the results.

Thanks to FCARPIO and all of the other contributors.


----------



## therapture

jbholsters said:


> What the hell kind of cars are you driving where the sub is the furthest speaker? I guess your subs aren't against the front wall of your trunks.



My G8 has the sub in the spare tire well, so to the driver's seat, it is indeed the furthest away as compared to the doors.


----------



## fcarpio

Jericho941 said:


> It's no wonder I was having such problems with TA as my "front/rear" settings were BACKWARDS!





Jericho941 said:


> Thanks to FCARPIO and all of the other contributors.


You are welcome, things like this will definitely come to light once you try this method.

Unfortunately, this and the other "big" time alignment method thread have a *TERRIBLE FLAW*, they will center the image in front of you. This will squeeze your sound stage on one side. *There is an easy way to correct it*:

You still have to do everything here, then:

- Pick a pair of speakers, say, the tweeters. Mute everything else.
- Out of the two tweeters pick the one with the most delay which should be the one closest to you.
- Find the center of your sound stage. I usually pretend I drive a Mercedes Benz and the center of my sound stage would be where the star in the hood goes.
- Now, playing a test tone that is well withing the tweeters range start decreasing the delay on the speaker closer to you. This will make the tone move across the sound stage towards the center.
- Repeat with the mid and mid bass.
- Now the sub will be slightly off, the ORIGINAL step for the sub can be repeated using cancellation. Even easier, if you have a phase knob use it to find the place where the sub sounds strongest UP FRONT.

That is it!

Now your center will NOT be directly in front of you and you will have an EVENLY spaced out sound stage with proper time alignment.


----------



## Woosey

fcarpio said:


> You are welcome, things like this will definitely come to light once you try this method.
> 
> Unfortunately, this and the other "big" time alignment method thread have a *TERRIBLE FLAW*, they will center the image in front of you. This will squeeze your sound stage on one side. *There is an easy way to correct it*:
> 
> You still have to do everything here, then:
> 
> - Pick a pair of speakers, say, the tweeters. Mute everything else.
> - Out of the two tweeters pick the one with the most delay which should be the one closest to you.
> - Find the center of your sound stage. I usually pretend I drive a Mercedes Benz and the center of my sound stage would be where the star in the hood goes.
> - Now, playing a test tone that is well withing the tweeters range start decreasing the delay on the speaker closer to you. This will make the tone move across the sound stage towards the center.
> - Repeat with the mid and mid bass.
> - Now the sub will be slightly off, the ORIGINAL step for the sub can be repeated using cancellation. Even easier, if you have a phase knob use it to find the place where the sub sounds strongest UP FRONT.
> 
> That is it!
> 
> Now your center will NOT be directly in front of you and you will have an EVENLY spaced out sound stage with proper time alignment.


Actually you don't with this method... because your tweeters and midbasses/midranges can be out of allignment.... They both center the stage like you say, but the allignment between the tweeter and mid can be way off.... 

If you do this, I recommend to allign the drivers on ONE side first, then the other side, and then delaying both or more drivers at the same time on the near side to move it to where you want it.. ( not preferred by me )

just my $ 0.02


----------



## fcarpio

Woosey said:


> Actually you don't with this method... because your tweeters and midbasses/midranges can be out of allignment.... They both center the stage like you say, but the allignment between the tweeter and mid can be way off....
> 
> If you do this, I recommend to allign the drivers on ONE side first, then the other side, and then delaying both or more drivers at the same time on the near side to move it to where you want it.. ( not preferred by me )
> 
> just my $ 0.02


Have you tried it? I wrote the original post and I am now making a correction. I wouldn't post a correction if I knew it didn't work. I tried it on my truck and it works well.

Maybe I am not understanding what you mean...

EDIT: I think we are saying the same thing.


----------



## Woosey

fcarpio said:


> Have you tried it? I wrote the original post and I am now making a correction. I wouldn't post a correction if I knew it didn't work. I tried it on my truck and it works well.
> 
> Maybe I am not understanding what you mean...
> 
> EDIT: I think we are saying the same thing.


Could be that it works for you, I mean: first get the allignment on one side good, then the other side

After that move the whole side ( left or right ) to get the center in the spot where you want it.. ( adjust levels while you do this too )

If i isolate everything except the tweeters, and i move them with ta they can be centered where I want them.

If I do this too with the mids isolated and after that with midbass isolated they can be all in the center.... BUT it's possible that the pairs of drivers need to be alligned too... tweeters alligned with the mids and midbasses, this requires ta on the pair of drivers : tweeters to mids, and those to midbasses

You get me? I can write a bit confusing sometimes 


Edit: made a quick sketch of what I mean

Left is with pairs not alligned but all in the center, right side is everything alligned and centered


----------



## Woosey

Read the first post again and indeed we say the same... Sorry should have done that again the first time... 


Sent from my Lumia


----------



## fcarpio

Woosey said:


> Read the first post again and indeed we say the same... Sorry should have done that again the first time...
> 
> 
> Sent from my Lumia


----------



## Woosey

fcarpio said:


>


But after you have set your tweeters, couldn't you just shift the other drivers the same amount as you shifted the tweeter?

So the relative delay between one side stays "as it was"?


----------



## fcarpio

Woosey said:


> But after you have set your tweeters, couldn't you just shift the other drivers the same amount as you shifted the tweeter?
> 
> So the relative delay between one side stays "as it was"?


Not necessarily because depending on your setup the tweeters may be spread further apart than the mids, or vice versa. If that is the case (most times it is) each driver requires a different delay that does not correspond to any other driver.

In my case I ended up with:

Left Tweeter - +2.38ms
Right Tweeter - +0.94ms
Left Mid - +1.29ms
Right Mid - 0ms (Base)
Sub - +1.27ms

If you do the math the mids and tweeters are close but that is due to my setup, it is better to do each pair at a time and whatever delay you end up with that is what it is.


----------



## tjvdm

fcarpio said:


> You are welcome, things like this will definitely come to light once you try this method.
> 
> Unfortunately, this and the other "big" time alignment method thread have a *TERRIBLE FLAW*, they will center the image in front of you. This will squeeze your sound stage on one side. *There is an easy way to correct it*:
> 
> You still have to do everything here, then:
> 
> - Pick a pair of speakers, say, the tweeters. Mute everything else.
> - Out of the two tweeters pick the one with the most delay which should be the one closest to you.
> - Find the center of your sound stage. I usually pretend I drive a Mercedes Benz and the center of my sound stage would be where the star in the hood goes.
> - Now, playing a test tone that is well withing the tweeters range start decreasing the delay on the speaker closer to you. This will make the tone move across the sound stage towards the center.
> - Repeat with the mid and mid bass.
> - Now the sub will be slightly off, the ORIGINAL step for the sub can be repeated using cancellation. Even easier, if you have a phase knob use it to find the place where the sub sounds strongest UP FRONT.
> 
> That is it!
> 
> Now your center will NOT be directly in front of you and you will have an EVENLY spaced out sound stage with proper time alignment.



Hi! 

First of all I would like to thank the OP for this wonderful TA instructions. I have 80prs and I've been setting up my stage and imaging for more than a year now. I've tried everything from pio's own auto TA to tape measure to pink noise etc etc etc. Honestly I've heard my sound stage already and is pretty happy with it. But it's only good for audiophile tracks and not for other genres. 

Until I saw this thread... (I haven't noticed this and it's been posted a long time already). 

All I can say is, WOW! It really worked! I've never EVER heard my system (and MUSIC) to sound this GOOD! My stage moved up. It became wider. It moved further out and I can honestly say I can hear live performances like I were really in front of the performers. And not only that but the tonality and the sound of any instruments became so realistic. Vocals became crisp and very clear. Music became so much fuller. In summary, I was very pleased how it turned out. 

But I have one tiny problem..

No matter how I try (as with other methods), I find it very difficult to align my subs to my midbass. Honestly I don't know if I did it right. I can't seem to hear anything. I tried overlapping sub and mbass up to 200hz and played mono test tone 100-200hz but still I can't find what I found on my other drivers. I did find it between mbass mids and tweets but not between my subs and mbass. 

I apologize in advance for this very noob question and also thank you in advance for helping us sq and car audio enthusiast achieving a better sound in our systems. 

Cheers!


----------



## fcarpio

tjvdm said:


> Hi!
> 
> First of all I would like to thank the OP for this wonderful TA instructions. I have 80prs and I've been setting up my stage and imaging for more than a year now. I've tried everything from pio's own auto TA to tape measure to pink noise etc etc etc. Honestly I've heard my sound stage already and is pretty happy with it. But it's only good for audiophile tracks and not for other genres.
> 
> Until I saw this thread... (I haven't noticed this and it's been posted a long time already).
> 
> All I can say is, WOW! It really worked! I've never EVER heard my system (and MUSIC) to sound this GOOD! My stage moved up. It became wider. It moved further out and I can honestly say I can hear live performances like I were really in front of the performers. And not only that but the tonality and the sound of any instruments became so realistic. Vocals became crisp and very clear. Music became so much fuller. In summary, I was very pleased how it turned out.
> 
> But I have one tiny problem..
> 
> No matter how I try (as with other methods), I find it very difficult to align my subs to my midbass. Honestly I don't know if I did it right. I can't seem to hear anything. I tried overlapping sub and mbass up to 200hz and played mono test tone 100-200hz but still I can't find what I found on my other drivers. I did find it between mbass mids and tweets but not between my subs and mbass.
> 
> I apologize in advance for this very noob question and also thank you in advance for helping us sq and car audio enthusiast achieving a better sound in our systems.
> 
> Cheers!


Good, you are almost there. Do you have a phase setting? I mean, one you can adjust and not just 0 or 180. If so, play with that a little while playing music. You'll know when you get it right.


----------



## tjvdm

fcarpio said:


> Good, you are almost there. Do you have a phase setting? I mean, one you can adjust and not just 0 or 180. If so, play with that a little while playing music. You'll know when you get it right.


I don't have one in my HU. I'll try to look for that in my amp if I have one and will try it out. Thanks fcarpio!


----------



## tgotovac

I too have a pioneer 80prs and have tried almost everything to get the TA right. ill be trying this method when I have a little free time and ill report back on how well it works.


----------



## Alextaastrup

Tried different methods of time alignemt but none of them were satisfactory for me (some - too complicated, some gave no expected results). Finally have found TDA softeware from Acoustic Power Lab. Demo version could be downloaded free from the fillowing link:
Acoustic Power Lab :: TDA

And it worked for me perfectly. Less than 40 minutes to adjust time delay i 5 channels car aoudio setup. My opinion - rather easy to use with amazing results. Delay visualization in 2D and 3D. It was the first time I decided to stop longtime nightmare of sound adjusting. Try this. I would like to hear responces from everyone to compare with my experience.


----------



## JVD240

Alextaastrup said:


> Tried different methods of time alignemt but none of them were satisfactory for me (some - too complicated, some gave no expected results). Finally have found TDA softeware from Acoustic Power Lab. Demo version could be downloaded free from the fillowing link:
> Acoustic Power Lab :: TDA
> 
> And it worked for me perfectly. Less than 40 minutes to adjust time delay i 5 channels car aoudio setup. My opinion - rather easy to use with amazing results. Delay visualization in 2D and 3D. It was the first time I decided to stop longtime nightmare of sound adjusting. Try this. I would like to hear responces from everyone to compare with my experience.


Seems like a bit of a sales pitch to me... Similar to your other two posts.


----------



## Alextaastrup

I am just sharing my positive experience with this company and its TDA product. If you could give me some tips for better time delay adjustment - I will be very pleased. I really spent a lot of time with other processors (mainly from Alpine) to adjust sub delay compared to the front speakers (passive) and was not happy with the results. I've read many posts on different forums, but only this one satisfied me (maybe you will have another opinion, which is quite normal). Why not to try this demo-version and to exchange opinions? I am new here, so do not blame me hard. Any constructive information on time delay is highly appreciated (still learning )


----------



## fcarpio

Alextaastrup said:


> Tried different methods of time alignemt but none of them were satisfactory for me (some - too complicated, some gave no expected results). Finally have found TDA softeware from Acoustic Power Lab. Demo version could be downloaded free from the fillowing link:
> Acoustic Power Lab :: TDA
> 
> And it worked for me perfectly. Less than 40 minutes to adjust time delay i 5 channels car aoudio setup. My opinion - rather easy to use with amazing results. Delay visualization in 2D and 3D. It was the first time I decided to stop longtime nightmare of sound adjusting. Try this. I would like to hear responces from everyone to compare with my experience.


This post was made so you don't have to use software or any other tools besides your ears and brain.


----------



## Alextaastrup

Great tips, bit it did not help me as I still have pure passive front and good deep scene was my dream for a long time. Agree with everybody that using ears is the best method. But my brain rejects to understand why I have to use much time if there are other methods available which give more accurate and quicker results. My ears cannot validate small changes in tuning. If you need to fine tune the system, ok, use your ears. It was not necessary for me.


----------



## fcarpio

Alextaastrup said:


> Great tips, bit it did not help me as I still have pure passive front and good deep scene was my dream for a long time. Agree with everybody that using ears is the best method. But my brain rejects to understand why I have to use much time if there are other methods available which give more accurate and quicker results. My ears cannot validate small changes in tuning. If you need to fine tune the system, ok, use your ears. It was not necessary for me.


Yeah, this method won't work very well with a passive setup. But then, no method is going to help you get good TA correction unless you go full active or you get a coax set for the front (this will get you closer without going full active).


----------



## subwoofery

Alextaastrup said:


> Great tips, bit it did not help me as I still have pure passive front and good deep scene was my dream for a long time. Agree with everybody that using ears is the best method. But my brain rejects to understand why I have to use much time if there are other methods available which give more accurate and quicker results. My ears cannot validate small changes in tuning. If you need to fine tune the system, ok, use your ears. It was not necessary for me.


Just disconnect your tweeters and try again. 
Sub to right mid to left mid. Then reconnect your tweeters to the setting that sounds best. 

One thing that is really important in order to work (active or passive) is to set your levels correctly (loudness of each drivers). 

Kelvin


----------



## Alextaastrup

fcarpio,

I am not sure you are 100% right talking about passive setup. Please read the following thread:

delay estimation and measurement

and you will understand that it is actually possible to adjust TA for passive front .
I was amazed with the results.

Nevertherless your method is fine and I know it has been used a lot.


----------



## fcarpio

Alextaastrup said:


> fcarpio,
> 
> I am not sure you are 100% right talking about passive setup. Please read the following thread:
> 
> delay estimation and measurement
> 
> and you will understand that it is actually possible to adjust TA for passive front .
> I was amazed with the results.
> 
> Nevertherless your method is fine and I know it has been used a lot.


Right. Sorry for the confusion, what I was saying is that "this method" does not work for passive setup unless the drivers that connected to the passive crossover are close together like a coaxial setup. Do I make sense?


----------



## jobo_ph

tjvdm said:


> Hi!
> 
> First of all I would like to thank the OP for this wonderful TA instructions. I have 80prs and I've been setting up my stage and imaging for more than a year now. I've tried everything from pio's own auto TA to tape measure to pink noise etc etc etc. Honestly I've heard my sound stage already and is pretty happy with it. But it's only good for audiophile tracks and not for other genres.
> 
> Until I saw this thread... (I haven't noticed this and it's been posted a long time already).
> 
> All I can say is, WOW! It really worked! I've never EVER heard my system (and MUSIC) to sound this GOOD! My stage moved up. It became wider. It moved further out and I can honestly say I can hear live performances like I were really in front of the performers. And not only that but the tonality and the sound of any instruments became so realistic. Vocals became crisp and very clear. Music became so much fuller. In summary, I was very pleased how it turned out.
> 
> But I have one tiny problem..
> 
> No matter how I try (as with other methods), I find it very difficult to align my subs to my midbass. Honestly I don't know if I did it right. I can't seem to hear anything. I tried overlapping sub and mbass up to 200hz and played mono test tone 100-200hz but still I can't find what I found on my other drivers. I did find it between mbass mids and tweets but not between my subs and mbass.
> 
> I apologize in advance for this very noob question and also thank you in advance for helping us sq and car audio enthusiast achieving a better sound in our systems.
> 
> Cheers!


Hello kabayan and fellow 80PRS owner!

Napansin ko lang yung post mo as I was reading this thread at DIYMA.

Bagong kabit ko lang yung 80PRS ko a week ago. Standard mode pa sa ngayon. Hinintay ko pa kasi dumating yung isa pang amp (arrived 2 days ago) at this coming weekend ko ma-wire para mag-network mode na.

Sa ngayon, just did measurements for custom TA at standard mode at played around with HPF and LPF settings to make things sound decent.

Susubukan ko din itong ear method for TA after ma-setup ko for active mode.

Nung time na nag-ear-TA method ka, naka-active setup ka na or standard pa lang? Pansin ko kasi walang phase adjustment kapag Standard. According sa manual, kung pareho yung freq cut-off at slope, automatic daw na ini-invert yung phase. Sa active mode lang ata meron phase adjustment.

Dun sa previous head unit ko na Kenwood (U5130BT), nung nag-reverse ako ng phase ng sub, saka ko lang narinig ng maayos yung sub.

Anyway, several months ago na din kasi yung post mo so baka by now, ok na tuning mo. Ako, magsisimula pa lang talaga mag-tweak.

Taga-Los Banos, Laguna nga pala ako. Wala namang malapit na reputable car audio shop sa amin kaya puro DIY lang ako. Enjoy mag-discover at matuto.

- Jonathan


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## T3mpest

For midbasses bandwidth limited pink noise works really well. 80-300hz. You can easily tell when it centers up.


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## subterFUSE

Sub'd


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## fcarpio

subterFUSE said:


> Sub'd


For some reason I though you tried this already. Have you?


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## subterFUSE

fcarpio said:


> For some reason I though you tried this already. Have you?


Sort of.

I did it with my subwoofers, after aligning my mids and horns via impulse response in REW.


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## ZAKOH

The DEH-80PRS TA has worked pretty well for me. First I let it do its thing with the autotune. Then I fine tune the time delays manually. The default result is too centered around the steering wheel. I prefer to have the center stage to be slightly to the right of steering wheel, which I accomplish while manually adding delay to woofers and tweeters, after listening each set in isolation.


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## fcarpio

And if this is too much, you can always use this: http://theguitarforum.net/ta/


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## subterFUSE

Just adding a small tip to this:

For some of the people asking about how to get a mono signal, *if you have a DSP with an Input Matrix* like the Arc PS8 or the Helix DSP/DSP Pro, you can simply route the Left Channel inputs to all of the DSP outputs temporarily.

That should create a mono signal out of anything you play.


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## fcarpio

subterFUSE said:


> Just adding a small tip to this:
> 
> For some of the people asking about how to get a mono signal, *if you have a DSP with an Input Matrix* like the Arc PS8 or the Helix DSP/DSP Pro, you can simply route the Left Channel inputs to all of the DSP outputs temporarily.
> 
> That should create a mono signal out of anything you play.


True.

If you cannot do the routing trick with your DSP you can generate a mono signal in Audacity (free).


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## santhosh

@fcarpio: First of all thanks for all the information provided in this thread on time alignment.
This seems to be easiest approach out of all other methods of applying TA.

I have the current setup.
Audison Bit 10 DSP(which i am trying to TA)
Helix P400 - Running Focal 165KR in Active Setup
RF Power-T500-1BDCP - Poweing Infinity Kappa 120.9W Subwoofer

I have trying to perform the steps you say, but then i face difficulty in isolating the sub and the midbass and finding the weakest signal.
I have tried it with a couple of songs which i have and also Pink Noise but still am not able to identify the weakest spot.

Subwoofer LPF set to 60 Hz
And midbass HPF is set to 80HZ and LPF at 3200 HZ


If i understood correctly i need to have the subwoofer and the midbass overlap.
Hence i changed the crossover to below.

Suwoofer LPF 80HZ
Midbass HPF at 60 HZ and LPF at 3200 HZ

Can you please correct if the above XO are the right way to have a frequency over lap.
Also even when i tried with above XO frequencies i find it tough in finding the weakest spot with pink noise.

Is it possible to use IMM6 mic to measure the DB level with MIC placed near drivers head rest and increase TA of Mid Bass to identify the weakest DB signal?
I plan to use Pink Noise for this purpose.

Will this help? I am not sure how good it would be though.


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## subterFUSE

I'm just going to throw out a guess here....

But I would think that if you held a dB meter next to your head and adjusted the TA with 1 driver inverted that the SPL would show a reduced level when the TA is in correct alignment? Then you just invert the polarity back to normal and boom, you're set.

Might only work for subs to mid, but could be a good start?


I might give this a try today to see if it works.


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## santhosh

subterFUSE said:


> I'm just going to throw out a guess here....
> 
> But I would think that if you held a dB meter next to your head and adjusted the TA with 1 driver inverted that the SPL would show a reduced level when the TA is in correct alignment? Then you just invert the polarity back to normal and boom, you're set.
> 
> Might only work for subs to mid, but could be a good start?
> 
> 
> I might give this a try today to see if it works.


Thanks for your reply,but is there a reson why it will not work for tweets?
The same principal applies for the tweets too ?
Tweet and mid bass alignment is based on the overlapping frequencies and we should look for the weakest signal?
Please correct me if i am wrong.


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## subterFUSE

santhosh said:


> Thanks for your reply,but is there a reson why it will not work for tweets?
> 
> The same principal applies for the tweets too ?
> 
> Tweet and mid bass alignment is based on the overlapping frequencies and we should look for the weakest signal?
> 
> Please correct me if i am wrong.



I was only guessing, but I would think the SPL difference on the sub and mid would be large enough to see on the dB meter. But maybe the tweeter difference would be so small that it's hard to see? I don't really know, but that was my guess. I could be wrong.


Sent from my iPad using Tapatalk


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## subterFUSE

I think it is pretty important to keep your crossovers where they are going to be because crossovers affect phase angle. If you move the crossovers to overlap and set time alignment, then move the crossovers to playing positions the timing will be off.


Sent from my iPad using Tapatalk


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## santhosh

subterFUSE said:


> I was only guessing, but I would think the SPL difference on the sub and mid would be large enough to see on the dB meter. But maybe the tweeter difference would be so small that it's hard to see? I don't really know, but that was my guess. I could be wrong.
> 
> 
> Sent from my iPad using Tapatalk


If this is the case then ideally listening by ears too will not make a point in identify the weakest signal as only a db difference can be heard right.
How else can some ta a tweeter by identifying the weak/thin signal.
Am confused now.
Some one can shed some light in this topic.


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## santhosh

subterFUSE said:


> I think it is pretty important to keep your crossovers where they are going to be because crossovers affect phase angle. If you move the crossovers to overlap and set time alignment, then move the crossovers to playing positions the timing will be off.
> 
> 
> Sent from my iPad using Tapatalk


As per the first post how do we create a frequency overlap then?
If i set xo to midbass hpf at 80 hz 12db slope and subwoofer lpf 80hz 12db slope. The overlap will be very minimal .
Sorry if may ask stupid questions i am pretty noob about this topic.


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## subterFUSE

I will test the dB meter out today. I have a good one.


Sent from my iPhone using Tapatalk


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## tyroneshoes

couldnt find the weak spot between my sub and reversed phase right woofer in a 2 way. Was hard to tell any difference until it started getting fat around 3 ms+. Woofers were playing full range and sub was lpd at 250hz all other speakers off. Tried mono pink noise and music. would using a 100hz sine be easier?

you can dl mono pink noise here btw

http://www.realmofexcursion.com/downloads.htm


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## fcarpio

santhosh said:


> @fcarpio: First of all thanks for all the information provided in this thread on time alignment.
> This seems to be easiest approach out of all other methods of applying TA.
> 
> I have the current setup.
> Audison Bit 10 DSP(which i am trying to TA)
> Helix P400 - Running Focal 165KR in Active Setup
> RF Power-T500-1BDCP - Poweing Infinity Kappa 120.9W Subwoofer
> 
> I have trying to perform the steps you say, but then i face difficulty in isolating the sub and the midbass and finding the weakest signal.
> I have tried it with a couple of songs which i have and also Pink Noise but still am not able to identify the weakest spot.
> 
> Subwoofer LPF set to 60 Hz
> And midbass HPF is set to 80HZ and LPF at 3200 HZ
> 
> 
> If i understood correctly i need to have the subwoofer and the midbass overlap.
> Hence i changed the crossover to below.
> 
> Suwoofer LPF 80HZ
> Midbass HPF at 60 HZ and LPF at 3200 HZ
> 
> Can you please correct if the above XO are the right way to have a frequency over lap.
> Also even when i tried with above XO frequencies i find it tough in finding the weakest spot with pink noise.
> 
> Is it possible to use IMM6 mic to measure the DB level with MIC placed near drivers head rest and increase TA of Mid Bass to identify the weakest DB signal?
> I plan to use Pink Noise for this purpose.
> 
> Will this help? I am not sure how good it would be though.


Are you using a mono signal?


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## tyroneshoes

I am using mono pink noise but had a hard time noticing it too

May try a 100 hz tone

got decent results using your linked tool but was hoping for results like others were reporting


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## subterFUSE

subterFUSE said:


> I will test the dB meter out today. I have a good one.
> 
> 
> Sent from my iPhone using Tapatalk



dB meter doesn't work. The numbers bounce around too much to get any idea of where the null point is.


Sent from my iPhone using Tapatalk


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## Alextaastrup

Some modification of the method of TA tuning:

First - TA settings for the right midbass and subwoofer according to actual distance between them and listening position (driver seat). XO - 4th order (gives zero phase shift).Then - out of phase sub (easy to do with my HU - just change between 0 and 180 degrees). Sinus signal at XO point (80 Hz). Fine tuning of the sub phase on amp (smooth 0-360 degrees). When the sound is weakest - here you are. Do not forget to change sub phase on HU back to its initial position. And it's done!

For secure reasons - I have repeated this procedure with the mic installed at headrest of the driver seat and dB tester (or RTA measuring program). With this equipment you do not need overlap as the most interesting point is XO frequency.


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## fcarpio

subterFUSE said:


> dB meter doesn't work. The numbers bounce around too much to get any idea of where the null point is.
> 
> 
> Sent from my iPhone using Tapatalk


A sine wave may be less bouncy. Can you give that a try? Now I am curious...


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## subterFUSE

fcarpio said:


> A sine wave may be less bouncy. Can you give that a try? Now I am curious...


Is that safe for the speakers to play? I've never used a sine wave with speakers connected, so just making sure I don't fry anything. LOL


I'll give it a try if it's safe.


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## sqnut

When I align the sub to the woofer in the door, I'm looking for the point where everything including what I know are sub frequencies feel like they are coming from the door woofer. Measured distance gets you into the ball park and once you are there, leave the sub alone and add/reduce the delay on the woofer. Go one way ~ 5" / 0.4 ms now back up to the origin point and go the other way by the same amount. You're looking for the point that gives you best sense of unison, best clarity (sub neither underwhelmed nor blurring the mid bass).

[edit] I always TA with actual music. [edit].


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## fcarpio

subterFUSE said:


> Is that safe for the speakers to play? I've never used a sine wave with speakers connected, so just making sure I don't fry anything. LOL
> 
> 
> I'll give it a try if it's safe.


Should be fine as long as you don't clip. No need to crank it either.


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## Alextaastrup

If you know exactly what to expect from your music (compared to home stereo, f.ex.) - it is fine. I prefer to use sinus wave at XO point (between sub and midbass) or pink noise, where I focuse on more wide frequency range.


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## eXistence

Sorry to bump an old thread. After all these years I never knew what TA was until now. So I have come to here to get some answers. I have no idea what to do. I am mechanically inclined with directions and a bit of quick learning. Anyways, lets move on to my setup:

I have a C6 Corvette. All speakers have been replaced with Arc Audio.

Headunit - Kenwood DDX 719

Amps - Pioneer GM-D9601 and a Pioneer GM-D8604

Crossovers + Tweeters - XDi 6.2Â*| Arc Audio

Rears - XDi 502Â*| Arc Audio

and just replaced my 2007 version Alpine Type R 10" DVC 4ohm with a 5th gen DVC 2ohm one. Won't be here till Friday.

So if you are in the car the furthest speaker away would probably be a fight between the sub or the passenger side speaker as I have a partition that sits basically right behind me. Like this:










I am going to list the speakers from furthers away to closest.

1. Sub
2. Passenger front speaker (These two can almost be a tie, but I will measure with a tape measure before I start)
3. Passenger rear speaker
4. Driver side front speaker
5. Driver side rear speaker

Now as you can see in the picture below the tweeters sit right above the front speakers (mids)










Now that we have that out of the way it is now time to do the TA. I have no idea where to start. My headunit has this built into it


> Triple 4.0V Pre-outs with Crossover System – Get the most out of your external power amplifiers by delivering 4.0V high voltage audio signal to maximize sonic performance. Using the built-in crossover system, you can also easily filter out unwanted frequencies to your speakers and subwoofers to tune your system to its maximum potential.


 On top of that it has, of course, an equalizer and a fader option too. Here is the manual about the Xover option. http://manual.kenwood.com/files/LVT2268-001A.pdf page 42 so you can skip everything.

So can anyone explain to me what I need in order to do this? I know it is 2015 now and they have apps you can download to use monotones. I do have an app called True Tone that I can play a range of frequencies. I used this app to set the gain on my speakers and sub so I would not have them clip at loud volumes. I hope this is enough info and I hope you guys can help. Thanks for reading.

eXistence


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## fcarpio

From the little I know of your gear I don't think you have time alignment capabilities in your current setup. You can still do time alignment when you run passive crossovers, but in my opinion is too much of a hassle. Is better to run active with a processor that can take care of the x-over points and also the eq and time alignment. Something like the Audison Bit Ten. There are MANY processors to choose from but that will give you an idea of what you need to look for. In most cases you will need a windows or mac computer to adjust the processor settings. There are also head units that have processor capabilities, but most can't touch a dedicated processor.

Something else you need to consider is the learning curve. For me it was pretty steep and the more I learn the more I realize I don't know much. Go for it, if you are up for the challenge. This forum was a huge resource for me and I learned a lot from all the folks here. Just know that if you decide to go with a processor your system will sound like ass until you know what you are doing, which in my case was a long time. But once it clicks the rewards are amazing.

Do your research to find out of this is for you.


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## eXistence

fcarpio said:


> From the little I know of your gear I don't think you have time alignment capabilities in your current setup. You can still do time alignment when you run passive crossovers, but in my opinion is too much of a hassle. Is better to run active with a processor that can take care of the x-over points and also the eq and time alignment. Something like the Audison Bit Ten. There are MANY processors to choose from but that will give you an idea of what you need to look for. In most cases you will need a windows or mac computer to adjust the processor settings. There are also head units that have processor capabilities, but most can't touch a dedicated processor.
> 
> Something else you need to consider is the learning curve. For me it was pretty steep and the more I learn the more I realize I don't know much. Go for it, if you are up for the challenge. This forum was a huge resource for me and I learned a lot from all the folks here. Just know that if you decide to go with a processor your system will sound like ass until you know what you are doing, which in my case was a long time. But once it clicks the rewards are amazing.
> 
> Do your research to find out of this is for you.


Thanks for the reply. I will say it sounds good as now, but I can't really compare it to the TA since it has never been done. So in order to do this I would need to buy some equipment and install some software? Also not sure if this means anything, but the settings I am running in the X'over are 40Hz for the sub, 120Hz for the mids and 150Hz for the rears. I hear those are pretty much the basics you'd want to do. I will do some more research and tackle it sometime. May be best to do in the winter since it'll be nice and cold and not hot here in Houston. Plus I have to run my car cause I will start sweating and I have loud exhaust so it is hard to hear over it when trying to tune the speakers.


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## Ninoslav

I start this morning only left midbass and subwoofer. I turn phase 180 on subwoofer. Now I dont understand what to hear-overall weak sound or subwoofer weak sound? Also on other speakers-do I listen overall sound or only sound of speaker that I am delaying?


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## fcarpio

Ninoslav said:


> I start this morning only left midbass and subwoofer. I turn phase 180 on subwoofer. Now I dont understand what to hear-overall weak sound or subwoofer weak sound? Also on other speakers-do I listen overall sound or only sound of speaker that I am delaying?


You are looking for weak sound on the two speakers that you are working on. Make sure that you are safely overlapping the crossover points so you get cancellation, the speakers are opposite to each other and that the volume on the two speakers are at a similar level.

Keep reading the earlier posts as some folks have shared very useful comments.


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## drop1

fcarpio said:


> You are looking for weak sound on the two speakers that you are working on. Make sure that you are safely overlapping the crossover points so you get cancellation, the speakers are opposite to each other and that the volume on the two speakers are at a similar level.
> 
> Keep reading the earlier posts as some folks have shared very useful comments.


No need to overlap. Simply play a test tone (sine wave) of the frequency at the crossover point . If the xover is 80hz use a 80hz tone. It's not that sensitive. A tone between 70 and 90 would work as well for a 80hz point on shallower slopes. For very steep slopes your target frquencies become a bit more important.


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## fcarpio

drop1 said:


> No need to overlap. Simply play a test tone (sine wave) of the frequency at the crossover point . If the xover is 80hz use a 80hz tone. It's not that sensitive. A tone between 70 and 90 would work as well for a 80hz point on shallower slopes. For very steep slopes your target frquencies become a bit more important.


I see your point, but ensuring that you have overlapping frequencies will save you some headaches. Also, matching volume levels will make things a lot easier.


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## andreheleyawan

This method can work with a passive crossover?


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## dvcrogers

Subscribed.


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## fcarpio

andreheleyawan said:


> This method can work with a passive crossover?


Read back a few pages, there is a small discussion about this.


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## ebrahim

Thank you for the time alignment link which is truly appreciated.




fcarpio said:


> Only change your x-over settings when needed for the TA. That is when you are setting the alignment for opposite speakers that don't have the same frequency range. When you are done bring them back to normal.
> 
> For example, if you are working on the sub and midbass, raise the sub frequency a little and lower the midbass a little to have them overlap. Do your TA and once you are done bring both back to normal. Now you are going to move to the two mid basses, here there is no need to change the crossover settings as these two speaker should cover just about the same frequency range. When done you are going to move to one midbass and one tweeter, here you will want to adjust the frequencies to overlap again. Lastly, before you do the two tweeters you need to bring the crossover settings back to normal.
> 
> In a nutshell, different speaker type, make the frequencies overlap. Same speaker type, bring crossover settings back to normal (same in both speakers) to overlap. Once you are done with the TA revert all your crossover settings to normal.


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## oliverlim

fcarpio said:


> Read back a few pages, there is a small discussion about this.


How would I go about aligning my setup? Have a bmw with a 3 ways active front and rear speakers. Have to leave my rear on for parking distance and with music it does send a high pass signal to the reads as well. I jus turn it down as much as I can and try to have it as the furthest speakers so that it does not detract from my front stage. Drive a rhd

My furtherst speaker distance in order is as follows

Left mid (on door)
Left tweeter (a pillar)
Left woofer (under passenger seat)
Right woofer (under my seat)
Right woofer
Right tweeter

Thanks!


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## hlucin8

Similar to the last post, I am running a 3 way active front stage, coaxial rears (for fill) and a single sub in a dual cab ute/truck )ford ranger T6 PX 2012)). 
Aligning the sub and the front stage has been explained perfectly. But what would you do with the rears? would running them at -20db to fade them out be enough to keep something for the rear passengers without affecting the front stage? or should they be aligned in as well?


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## subterFUSE

Rear speakers should be mixed differentially, and then delayed a lot.


Sent from my iPhone using Tapatalk


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## hlucin8

subterFUSE said:


> Rear speakers should be mixed differentially, and then delayed a lot.
> 
> 
> Sent from my iPhone using Tapatalk


Can you please explain this a bit more? What do you mean by differentially mixed? and delayed a lot or attenuated a lot.

I was planning to attenuate them substantially so they're audible from the rear but don't impact the front stage. but should they be TA'd into the mix so if there is a bleed into the front it isn't as noticeable?


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## subterFUSE

hlucin8 said:


> Can you please explain this a bit more? What do you mean by differentially mixed? and delayed a lot or attenuated a lot.
> 
> I was planning to attenuate them substantially so they're audible from the rear but don't impact the front stage. but should they be TA'd into the mix so if there is a bleed into the front it isn't as noticeable?


Differentially mixed means that you send both left and right signals to each rear speaker, but you invert one of the inputs.


So the left rear speaker gets Left positive, Right negative feeding it.

The Right rear speaker gets Right positive, Left negative feeding it.


The result of this mixing of inputs is that center-stage located sounds are cancelled out. You won't hear any centered vocals from the rear speakers, just ambience from the edges of the soundstage.



And then you need to add a considerable amount of delay to the rears to overcome the precedence effect, and to give the added sense of room size.


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