# RePhase , loudspeaker linearizarion tool



## oabeieo (Feb 22, 2015)

You can make your phase flat , very easy to do , just need minidsp 2x4hds to do the task 

a pair of them gives 8ch. Most powerful accurate dsp on the market for its size per channel. Unlimited eq , TA, true phase correct.

gives tonal balance better then 1st order crossovers.


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## Granite (Jun 3, 2020)

Says it can be implemented with any hardware. Like a helix dsp? How is that possible?


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## oabeieo (Feb 22, 2015)

Granite said:


> Says it can be implemented with any hardware. Like a helix dsp? How is that possible?


any hardware that accepts FIR filtering

sorry helix 🧬…. Not today


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## oabeieo (Feb 22, 2015)

Fir filters are easy to implement. Very easy , and it’s easy to get it right!

a linear phase crossover is so so much easier to implement then a minimum phase crossover.
this can make a bad sounding speaker location sound superb….

and it’s crazy when you hear you system do stuff and do it so extraordinarily well and sound top notch. It’s like , you can definitely definitely tell there’s some serious dsp behind the scenes.

minidsp out performs helix and mosconi so incredibly much it’s no comparison at all anymore.

it literally leaving them behind in the dark ages of dsp. This is truly the only way to go if your truly serious about the absolute best in SQ and performance in a car.

it’s such a game changer I can’t believe so many ppl pass it by and opt for these “others” that can do minimum phase corrections good, but that’s it.

when yor car changes the behavior of a speaker so much that the only way to get it to sound right is to go in and do time alignment by frequency, this is the answer.


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## saltyone (Feb 2, 2019)

Time alignment “by frequency”? 😮


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## oabeieo (Feb 22, 2015)

saltyone said:


> Time alignment “by frequency”? 😮


yes sir.!!

Heya hit me back if you still need help w your car.
Or if you have someone else doing it , but need it tuned lmk (if you found someone else that fine also there’s lots o good installers)


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## chasingSQ (Sep 25, 2017)

can this be done with my 8x12 dl ?


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## oabeieo (Feb 22, 2015)

chasingSQ said:


> can this be done with my 8x12 dl ?


no , Dirac has control over the fir , Dirac does all of its correction in the fir sections

it has the hardware to do manual fir , that’s why it can run Dirac


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## SiW80 (Mar 13, 2019)

Assume this and DL do different things so can one substitute the other?


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## dumdum (Feb 27, 2007)

SiW80 said:


> Assume this and DL do different things so can one substitute the other?


Dirac live uses fir to achieve a similar result, basically making a near perfect impulse response 👍🏼 Dirac is automated with an algorithm, this is doing it diy by yourself


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## gijoe (Mar 25, 2008)

Is this the biquad feature that I have on my miniDSP 6x8? I never really looking into that feature, all I know is you can import files from REW, but never got around to figuring it out.


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## oabeieo (Feb 22, 2015)

So no it’s not biquads , it’s fir samples 

and yes dirac does something diffrent , it makes the system minimum phase and makes left and right coherent after Left and Right eq is done

this makes the phase flat at the speaker…

the combo of both is stunning

dirac by itself sometimes misses it in tonality.Just a little, this tightens that up.

this makes all of the frequencies come out at the same exact time….

it’s very similar sound to using all 1st order filters, except better.

you don’t have to use Dirac with this , Dirac makes it a lot faster and easier to tune.

The 2x4hd does have input eq so you could do a gloabal target after this and make it work exceptionally good.

it’s surprising how good the system sounds after this step. It’s remarkable. It really brings things together in a way that just can’t be done otherwise


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## chasingSQ (Sep 25, 2017)

So your using 2 processors ?


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## oabeieo (Feb 22, 2015)

chasingSQ said:


> So your using 2 processors ?


Rn I use 6 dsps


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## oabeieo (Feb 22, 2015)

So , when I competed in iasca I got a score of 229, everything was pretty much perfect except my R of center was a tiny tiny bit too the right. And I could also hear it , so the judge was correct 

Now , it’s absolutely perfect! And before my right wouldn’t go directly to be parallel with my right shoulder… it was at the right dash speakers, that was right..

Now Right is to my right shoulder, it sounds like sound if coming from my side , and same with left. The left also limit was at the speaker, now it’s at my left shoulder… 

that’s crazy!!! I have no speakers there ! I was just driving and was like , hummmm I wonder if the test tracks still work right…. Yes! And way better…. It’s arguably perfect now.


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## chasingSQ (Sep 25, 2017)

I how many drivers are you using for 6 dsp’s ?


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## oabeieo (Feb 22, 2015)

chasingSQ said:


> I how many drivers are you using for 6 dsp’s ?


13

OpenDrc 
Ddrc22 
3 2x4hds 
Ambio sonics 2x2 rears processor


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## dumdum (Feb 27, 2007)

oabeieo said:


> So , when I competed in iasca I got a score of 229, everything was pretty much perfect except my R of center was a tiny tiny bit too the right. And I could also hear it , so the judge was correct
> 
> Now , it’s absolutely perfect! And before my right wouldn’t go directly to be parallel with my right shoulder… it was at the right dash speakers, that was right..
> 
> ...


That makes no sense… perhaps draw a picture of where perceived locations of left and right are 👍🏼


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## oabeieo (Feb 22, 2015)

dumdum said:


> That makes no sense… perhaps draw a picture of where perceived locations of left and right are 👍🏼


yeah no problem …. , yeah before R and L were at the dash mids and RC was just a little to right
Now left and right are to my sides


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## dumdum (Feb 27, 2007)

oabeieo said:


> yeah no problem …. , yeah before R and L were at the dash mids and RC was just a little to right
> Now left and right are to my sides
> 
> View attachment 355062


That’s not really good, it’s akin to rainbowing left and right

a stage shouldn't wrap around you… it should be flat and have width and depth beyond a flat front… it’s incredibly hard to achieve especially with the drivers side coming towards you which is very common in lots of cars


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## oabeieo (Feb 22, 2015)

dumdum said:


> That’s not really good, it’s akin to rainbowing left and right
> 
> a stage shouldn't wrap around you… it should be flat and have width and depth beyond a flat front… it’s incredibly hard to achieve especially with the drivers side coming towards you which is very common in lots of cars


No , not 🌈 rainbow , that’s where the image is on the floor on the left and right then rises to the center 

this is not that…. What your described

this a far more correct , it’s not all the way to the sides , but a lot more , like a little bit closer then my side mirrors, and the height is up high!

I’ve had cars that rainbow (especially horns in the HF)

this everything is up high, nothing to the floor or low at all….

and as far as depth goes , before L and R were at the dash speakers , now it’s more outside the car and at the mirrors mostly a little closer tho…

as far as actual perceptions as imaging , it feels like a semicircle or half doughnut of sound outside just outside the boundaries of the car…

what you described is exactly what I just had before the phase fix….

maybe my pic suck , I’ll do a video


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## oabeieo (Feb 22, 2015)




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## chasingSQ (Sep 25, 2017)

well if does exhibit a rainbow effect , im sure he can add another processer to fix that .


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## oabeieo (Feb 22, 2015)

chasingSQ said:


> well if does exhibit a rainbow effect , im sure he can add another processer to fix that .


very cute… ha! … ….. dont tempt me lol …..


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## dumdum (Feb 27, 2007)

Note I said akin to rainbowing… as in its horizontal rainbowing not down on the left and right in a vertical plane

Your left and right extreme sides should be as far away as the centre in a good well setup system, yours steps back from left to left centre and then is roughly flat through centre and to right centre and then steps further back into the car for right

put simply with a perfect car you should be able to draw a line through left and right looking from above and the other three points will be on that line not closer to you

yours is all the x’s… a perfect stage will be the circles as left and right with the x’s on a flat line

You’ve got width by reflections and rainbowed it horizontally…

you’d maybe get a few extra marks for width in Emma but lose 4-5 marks for the distance to stage as it’s the closest point to you with the 2022 disc, on the 2018-2019 disc depth to stage you’d have scored well as it was on the depth in the centre…


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## oabeieo (Feb 22, 2015)

dumdum said:


> Note I said akin to rainbowing… as in its horizontal rainbowing not down on the left and right in a vertical plane
> 
> Your left and right extreme sides should be as far away as the centre in a good well setup system, yours steps back from left to left centre and then is roughly flat through centre and to right centre and then steps further back into the car for right
> 
> ...


Okay that’s a lot like it was !!!

okay so , I’m going to have to try and get some of that back then

But I want listen like this for awhile … it sounds really dam good like this…. I’ll definitely try and get it back more like it was 

So I donot my scored lower next year that’s for sure !!!


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## dumdum (Feb 27, 2007)

oabeieo said:


> Okay that’s a lot like it was !!!
> 
> okay so , I’m going to have to try and get some of that back then
> 
> ...


At the end of the day it’s a balance unless you go really extreme like eldridges nascar (very clever from what I gather about it) or black Betty for example

especially for competition in a normal car, width vs depth to stage vs depth of stage vs tonality is all a big play off and having one really well is often not the best way to go… a very good average often trumps one being really good


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## oabeieo (Feb 22, 2015)

dumdum said:


> At the end of the day it’s a balance unless you go really extreme like eldridges nascar (very clever from what I gather about it) or black Betty for example
> 
> especially for competition in a normal car, width vs depth to stage vs depth of stage vs tonality is all a big play off and having one really well is often not the best way to go… a very good average often trumps one being really good


yeah that makes a lot of sense….

At least I know how to put it back…. It’s kinda cool being able to actually move things around a little…

So , it looked like Dirac intentionally put a wrap around 630hz …. I am very curious if that was meant to be there 

I’m going to be doing a lot of testing this week….. I want to figure this out now


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## dumdum (Feb 27, 2007)

oabeieo said:


> yeah that makes a lot of sense….
> 
> At least I know how to put it back…. It’s kinda cool being able to actually move things around a little…
> 
> ...


I’ve just ordered a 2x4hd as fir interests me a lot, I will be using it in my workshop system initially, if it works I may get a flex digital for the car


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## oabeieo (Feb 22, 2015)

dumdum said:


> I’ve just ordered a 2x4hd as fir interests me a lot, I will be using it in my workshop system initially, if it works I may get a flex digital for the car


now we’re talkin !!!

I think you’ll be hooked, man that **** is like crack
I’m actually really excited to see what you do with it…. I’ll take a back seat to that for sure !!


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## dumdum (Feb 27, 2007)

oabeieo said:


> now we’re talkin !!!
> 
> I think you’ll be hooked, man that **** is like crack
> I’m actually really excited to see what you do with it…. I’ll take a back seat to that for sure !!


It will be fitted in my workshop two way initially so I can get a feel for it and it’s a very predictable phase ‘smiley face’ for want of a better description, so I will use the 2x4 hd as a crossover/eq/fir machine to see what can be done with the workshop system. I might even give the system an upgrade from its sb acoustics sb17nrx2 and sb19 c-0004 tweeters to satori textreme 16cm and bliesma beryllium tweeters 😎


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## oabeieo (Feb 22, 2015)

dumdum said:


> It will be fitted in my workshop two way initially so I can get a feel for it and it’s a very predictable phase ‘smiley face’ for want of a better description, so I will use the 2x4 hd as a crossover/eq/fir machine to see what can be done with the workshop system. I might even give the system an upgrade from its sb acoustics sb17nrx2 and sb19 c-0004 tweeters to satori textreme 16cm and bliesma beryllium tweeters 😎


nice shop system,
Yeah I think you’ll really like it , 

I have been doing close mic gated 4cy measurements about 6-10” away from speaker , thenhaving REW shift the IR, and have been getting really clean phase data ,

I basically make the driver flat all the way through it’s range with output eq first (I’ve been doing the eq from listening position but you can do it at speaker too)

then once I have phase measurement and aiR shifted, I export as text and input measurement into rephase , then make phase flat, you also can do some eq in rephase.

it’s been working really good,

I don’t mess with anything below 100hz, but as far as getting all the drivers to have the same tilt up in phase below 100hz, I was using some out of band APFs in the minidsp side around 10-30hz to move the phase enough so they all match, because the fir won’t let me adjust that low

So utilizing some all past filters in the subsonic has helped me some, just have to remember to turn that off in rephase and turn it on in the Mini Dsp… so that portion of it you don’t get to see it on the rephase screen but you know it’s doing what it’s doing because you were able to simulate it in rephase. (If that makes sense) 

and A different subject, last nite I tried running Dirac over the phase correction with the sub off
My stage is a lot more like it was now and still have phase correction 

Dirac wanted to put left and right out of phase around 20-30hz because the door speakers at listening position was out of phase there ,
So having the sub off allowed it to make that correction properly , then I had to add the sub back in and fix the phase shift it caused using my OpenDrc

so , it still rainbows a tiny bit in that horizontal way, but it’s way better then it was before still , but a lot more like you described

if there was a way to have it attenuate only left and only right and any Signal that has any mix of both like center information for example would not be attenuated.. if I could somehow make a processor do that and look at left and right information like that I could get it to do exactly what you were saying perfectly… this is really hard to do lol


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## oabeieo (Feb 22, 2015)

Never mind , you have smaart …. I forgot … 

you’ll have an easy time then. 😎


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## dumdum (Feb 27, 2007)

So initial install of the 2x4hd… it’s in the system and working… what I didn’t realise is you can pipe usb audio straight into this little box… no need for optical cables and a topping, usb to the pc and all audio is sent digitally and sounds superb as I’d expect from a digital audio signal, and as I had the dsp.3s dialled back on its outputs the volume is identical even though it’s 6v vs 2v

I literally copied settings over from the dsp.3s and away I went, and it comes with a remote as well… it may just find it’s way into my system before the dsp pro 3 via analogue if the iPad also sees it via usb and have full fir for the car, fir testing will commence tomorrow once I’ve taken a measurement of the speakers and made fir files for each


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## oabeieo (Feb 22, 2015)

dumdum said:


> So initial install of the 2x4hd… it’s in the system and working… what I didn’t realise is you can pipe usb audio straight into this little box… no need for optical cables and a topping, usb to the pc and all audio is sent digitally and sounds superb as I’d expect from a digital audio signal, and as I had the dsp.3s dialled back on its outputs the volume is identical even though it’s 6v vs 2v
> 
> I literally copied settings over from the dsp.3s and away I went, and it comes with a remote as well… it may just find it’s way into my system before the dsp pro 3 via analogue if the iPad also sees it via usb and have full fir for the car, fir testing will commence tomorrow once I’ve taken a measurement of the speakers and made fir files for each


oh yes usb audio , and they have an asio driver for it also , so running impulses directly into it from REW or smaart should be very low latency and you can select 96k it’s native SR.

I have one as a shop source as well , when my deck dies , I will make one a deck as well

that’s awesome , and you got it pretty dang quick.

Happy thanksgiving!


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## oabeieo (Feb 22, 2015)

So let me talk about an OpenDrc for a sec
(Or hq player or roon @CAMSHAFT ) 

to do a Dirac level (actually kicks the **** out of Dirac) tune, here’s some easy easy easy steps to do it in rephase with an OpenDrc

1 do moving mic averages and make it flat! RTA IN REW

that will mean many iterations of adding peq into the OpenDrc and then moving those peqs to peqs in rephase , it takes about 5 rounds because the peq slot in OpenDrc only has 6 spots , so do the first 6, copy those settings to that channel in rephase and convolve and send fir , then clear the 6 peqs and go for the next 6 , do that as many times as you need , there’s 16 banks of 16bands of eq in Rephase…

do that for each channel, just focus on frequency responses , if it decorrelates who cares we’ll fix that later…. Make left and right flat as you possibly can using MMM.

2. Now make 9 sweep measurements for left and 9 sweep measurements for right in separate REW instances or keep track of left and right using checkboxes for each ch. use a 15cy FDW (just do it) we don’t want too many reflections mixing together

make a parallel piped around your head , the 1st measurement must be directly between your ears. (Copy cat Dirac box) make the sweeps.

3. On each measurement for left individually go to the control box on top right and select “ESTIMATE IR DELAY”. Then select shift IR and move impulse (the middle box) or just shift IR. Do that for each measurement! , then do that again for all the right measurements

4. Go to ALL SPL tab and open gear ⚙ drop down….

select all the left measurements and select 1/3 SMOOTHING then TIME ALIGN MEASUREMENTS. Then select VECTOR AVERAGE. That will make a average measurement that will be used to make the phase correction for that ch…

do that again for the right ch

5. For the left avg selected, click export measurement as text , go to next screen save it as something

6 open your eq settings in rephase for that ch, then click IMPORT MEASUREMENT from drop down and select your saved text measurement

7 go to ranges button and select the db scale to make your Measurement visible (70db to 100db works good)

8. Use phase eq and linearizarions (LR4 linearizarion removes 1 wrap) the combo of those make phase flat from 100-1.6khz , then generate filter send to that ch , then , do the other ch , when you import measurement for other ch , try to use the same phase eq settings as the previous ch and see where phase is , they will be close !!! Then make slight adjustments so there both flat from 100-1600hz (ignore everything else) send that to dsp

9 take a listen to perfect correlation and stunning stage depth

Enjoy


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## oabeieo (Feb 22, 2015)

Heres my home setup The right has the sub (dontask why) but you could getr something like this.
the sweeps show frequency responce issues, thats OK your MMM measurements were perfect. That is because where the mic position was to get the phase measurements are diffrent from MMM measurement points

you could definatly use your sweeps and make your eqs using those it works great its time consuming and IMHO not as good as MMM, what your hear with MMM is a better representation. Of cource your sweeps will make the phase off because the diffrent measuring techquines, but it wont be by very much.

If sweeps wortk better for you and your dedicated to the 50-100hrs it takes to get a really good correction, GO FOR IT its worth it... This method gets your better then Dirac in about 1 HR.....

I definatly recomment using the sweeps to do peq MORE. It just takes more time. So be patient. Either way nets you a fantastic sound... Youll be miles better then you were with multiple wraps before.

@dumdum you should give it a whirl, if you haven’t already….


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## oabeieo (Feb 22, 2015)

If someone wanted to make the system minimum phase, you could use the same process except extract the minimum phase on the vector average , then select EXCESS PHASE, then export the excess phase measurement to rephase and make that flat ,

that will remove the reflections and make the system minimum phase…..

there are some very good benefits to a system that is minimum phase.

that method above does the measured phase (all of what you hear)

if you have good coherence, I would consider strongly to just do the excess phase…. It will remove any hollow sounds from the dips (won’t fix the dips) but will make them sound tonally Proper. Thanks


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## oabeieo (Feb 22, 2015)

I’m my car I used that method on an OpenDrc but did 30 measurements per side , tight grouped and did the box and levels in between the box as I worked into the center point 1st measurement 

My buddy (who is a whizz) on diy audio (wesayso) says to use 3 measurements per point for complete accuracy…

It takes longer, but my goodness, talk about the bass to the front….


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## cathul (Jul 2, 2018)

And if you don’t have a miniDSP box you could just write the impulse response to copies of your tracks and use these from your phone (ffmpeg can do that).


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## oabeieo (Feb 22, 2015)

cathul said:


> And if you don’t have a miniDSP box you could just write the impulse response to copies of your tracks and use these from your phone (ffmpeg can do that).


hey!!! Nice to see u on

Thats An absolutely brilliant idea!!

yes you could convolve your tracks on audacity

Ha back in the day I used audacity to do time alignment and burn tracks to cd 

yes if someone competes, you could make your test cd on that…. That is such a good idea


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## cathul (Jul 2, 2018)

Problem with Audacity is that it’s hard to automate the process. Fffmpeg is a command line utility so with power shell or a Linkx shell you can write a script where you can do all your tracks automatically.


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## dumdum (Feb 27, 2007)

oabeieo said:


> I’m my car I used that method on an OpenDrc but did 30 measurements per side , tight grouped and did the box and levels in between the box as I worked into the center point 1st measurement
> 
> My buddy (who is a whizz) on diy audio (wesayso) says to use 3 measurements per point for complete accuracy…
> 
> It takes longer, but my goodness, talk about the bass to the front….


Bass upfront only requires a single measurement per driver from midbass and sub


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## oabeieo (Feb 22, 2015)

cathul said:


> Problem with Audacity is that it’s hard to automate the process. Fffmpeg is a command line utility so with power shell or a Linkx shell you can write a script where you can do all your tracks automatically.


seriously ?

I would love to see that, you should develop a Phone app for us that’s a music player that can read title in Spotify and be able to convolve from our phones….. 

What I really would love if tidal had a 2ch convolver built in and at least 3 rooms to select


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## oabeieo (Feb 22, 2015)

dumdum said:


> Bass upfront only requires a single measurement per driver from midbass and sub


that correct,

I’m talking joining the mids n highs to the bass (not the other way around) when I said that,

it makes everything go to the front lol 

did you get an OpenDrc?

Im waiting till my wife gives me the go ahead to get LE , it’s my Christmas present…. I’m pretty excited to give it a whirl!


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