# How to EQ the REW measured response curve.



## therapture (Jan 31, 2013)

OK, I have the mic, I have the pc, I have REW. I know how to measure somewhat. Below is my response, from what I consider to sound pretty damn good. What I am curious about, is...

1. If I have a 2db dip at a certain spot in the measured response, do I need to use EQ +2db into that spot to try and cure it? In other words, is it a real respresentation of the actual db levels across the range (assuming it is)?

2. I have some house curves I want to try, just to see what it's all about.

3. I suppose I need to measure each side independently, and compare those plots, to see if I really have a well balanced LH-RH response. Once that is verified and matched, then I would cut/boost both sides by the same amount, to keep the same differential for tonality while trying to fix peaks or dips?

4. And, what db differential between one frequency range and the next, should I worry about trying to fix? Like in the pic below, see the 4.5k-5k peak? I want to drop that, so on my EQ, I assume I would simply cut that band (maybe Q as well) to get that in line with the neighboring frequencies.

Sorry for so many questions...the pic shows the 3 measurements (mic at driver's headrest, moved from dead center, then right, then left), with the line indicating the averaged response


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## evangojason (Feb 12, 2010)

Use the housecurves and auto EQ!!! Weather you like the curves or not you will learn a lot. When balancing left and right in auto eq make sure your target level stays the same. My first run I just hit "set target level" and take note of what level it sets. Then manually enter the level for the other side or repeated runs. I like to have music playing while entering the the filters into my 3sixty3. Being new to this I think it "connects" what I see in the RTA, the numbers in the auto eq filters, and what I'm hearing. I can get an almost perfect left and right balance this way. Should have captured an image today, maybe tomorrow.


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## lithium (Oct 29, 2008)

i prefer to only make cuts. focus on the larger peaks first and verify by ear that the frequency response is improved. 

yes, work on each side independently


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## therapture (Jan 31, 2013)

evangojason said:


> Use the housecurves and auto EQ!!! Weather you like the curves or not you will learn a lot. When balancing left and right in auto eq make sure your target level stays the same. My first run I just hit "set target level" and take note of what level it sets. Then manually enter the level for the other side or repeated runs. I like to have music playing while entering the the filters into my 3sixty3. Being new to this I think it "connects" what I see in the RTA, the numbers in the auto eq filters, and what I'm hearing. I can get an almost perfect left and right balance this way. Should have captured an image today, maybe tomorrow.



So, I can do this with just my laptop, mic, and 363?

I do not have a loopback (?) set up, and not even sure if my laptop has the sound card to do that with, it's just a Dell Inspiron.


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## evangojason (Feb 12, 2010)

Yes you can. I'm guessing you already loaded your cal file for the mic into REW right? To calibrate my sound card i just loop the audio output and input. The biggest problem for me was searching the laptop and turning off ALL the audio enhancements, effects, and corrections for mic and speaker. Could not calibrate correctly till this was done. Once I did that the calibration went smoothly. I found a video on youtube showing the process, just search "rew soundcard calibration". Then load the housecurve, measure average and smooth one side, hit eq, set your level like explained above, hit match resp., and enter the filters to the correct driver on the 3sixty. Then do the otherside and repeat as needed. Using 1/2 smoothing will help in the beginning. If you only want to make cuts set your target level below your measurements. Some of the "Q"s the auto eq spits out is well above the 3sixtys 0-6 range. Ones that are close I enter 6 the ones that are really high I ignore. I think there's a way to force it to you 0-6 but haven't found it yet. That should be enough to get you started. I just learned all this stuff myself in the last couple months so I'm not a pro, but I have read everything I could find on the subject recently. Hope it helps.


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## mojozoom (Feb 11, 2012)

rapture,

You only need the loopback connection in REW if you want to make comparable impulse measurements with extreme accuracy. Time alignment kinda stuff. So no worries if you're doing FR testing.

If you use the EQ screen you can directly see the impact of adding boosts or cuts. Make sure you have clicked the box for both the oringinal test and the "Predicted".

If you want to play around in a more linear format to get a better understanding of what's happening when you do this stuff, you might want to try switching to working in 1/3 octave EQ style only, and come back to parametric later.

If you look at my posts in this thread
http://www.diymobileaudio.com/forum/technical-advanced-car-audio-discussion/144455-quick-tip-using-auto-eq-roomeq-rew-2.html
you'll be able to see how to use REW as a vitrual 1/3 octave EQ essentially, and then you can transfer those settings to your 360.3.


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## mojozoom (Feb 11, 2012)

I forgot to mention -

You can capture a nice plot of any results screen in REW by clicking the little camara in the upper left corner. But if the phone pics are easier for you that's cool too -


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## therapture (Jan 31, 2013)

OK, now that I am utterly confused...:laugh:

I followed the steps, I have the EQ plot generated...but some questions. Forgive my noobness.

1. Do I start with my EQ zeroed for the initial measurements? 

2. I see the plot it generates, but the ranges are very oddly spaced, from very close together in the low freqs, and very large in the higher ranges up to 10k. What about 1/3 or 1/6 octave smoothing, I see no relation.

3. Am I supposed to just key in the freqs it lists and set the cut/gains as indicated? Do I just set them only on one side or the other? 

4. In step 4, how do I set the SPL scale to 0 db?

I must be doing something wrong...


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## therapture (Jan 31, 2013)

Another screencap...


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## evangojason (Feb 12, 2010)

You don't have to start with it zeroed but it will help having all filter working towards the same goal and save you a some eq bands. 

My sub and midbass always require the most "work", I think it's just the way it is. 

Set the filters for the drivers you measured. If you measure an entire side, put the filter to the driver covering that frequency. 

After hitting "EQ" under "target setting" you will see "target level (db)" and "set target level". "Target level" is to manually set the level, "set target level" will automatically set level. You can use automatic the first time, but like I mentioned before take note of the number and always set the same level!!! If it automatically sets -9.5, I'll set it for -10 to make it easier and set it for -10 every time.


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## therapture (Jan 31, 2013)

I'm even more lost I think. 

-I measured the RIGHT side + SUB to create the "A" plot
-Then the LEFT side + SUB to create the "B" plot
-Then I averaged them (for grins) but then I did the A/B generation to get the plot before going to the EQ button, with only the A/B plot selected. I just typed "0" into the "Target Level" instead of hitting the "Set Target Level" link.

Am I supposed to turn the sub OFF, and measure ONLY one speaker at a time? I only have the HAT Imagine in co-ax mode in each front door,so effectively I only have THREE speakers (since the tweet is running on the same amp channel as the mid driver)



evangojason said:


> You don't have to start with it zeroed but it will help having all filter working towards the same goal and save you a some eq bands.
> 
> My sub and midbass always require the most "work", I think it's just the way it is.
> 
> ...


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## evangojason (Feb 12, 2010)

Here's how I do it. (I always have my HU at the same volume)

-Turn off left side, leave on right side and sub.

-Measure the sub 6 times, average, and smooth. (start with 1/2 till you get the hang of it)

-Hit "EQ", under target settings hit "set target level", A number will show up in "target level", round it down to an easy number to remember like -9.4 to -10.

-Under "filter task" enter setting from the other thread, (20-10000) (3db) (3db) (1db) and hit "match response to target"

-When filters are generated hit the two arrows to put filters in order. start entering filters for the sub, when I get to the subs crossover frequency start entering to midbass, then midrange, then tweeter. 

-I will usually repeat those steps 1-6 times depending on how much time I have. (making sure to set the same level as before)

-Turn off the right side and turn on left side, Measure left side and sub and repeat the other steps. 

If you match both side to the target curve at the same level it should balance left and right. When Im done I take measurements to verify. Hope this helps, My first week was the same way. Maybe start by just doing each side once and spend some time listening to it. I've also heard to take lots of break.


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## mojozoom (Feb 11, 2012)

Doing one at a time is the best. It'll be alot easier since you are running passive as well.

First, pick a housecurve you want to shoot for and make sure to select it under Preferences.

Turn off the sub and left side, and sweep the right side. Try it a few times, increasing the volume each time untill you get as close to 0 on the headroom as possible. That's the head unit setting to test at for the rest of your session. Once you hav ethe measurement taken you can click the X on the others to drop them off and keep the last one. Click the little pen and select red for a color (red=right, easy to remember).

Now turn the right side off and the left side on, and sweep it. Click the pen and change the color to green or anything but red.

Now click on the right side measurement again and then click EQ. Make sure the legend under the FR plot has the boxes checked for Predicted and Target. Click Target Settings, select Speaker Type = Subwoofer, Crossover = 24 dB/octave, Cutoff = 3500, LF Slope = 24 dB/Octave, LF Cutoff = 80 (I made these up - fill in the correct LP and HP numbers for your setup).

Then click Set Target Level. REW will move the bandpassed housecurve to where it feels best lines up with your data. Now you can move it up or down via the Target Level box.

Adjusting the location of the target curve should really be done based on the location of non-minimum phase areas in your FR. We'll deal with that later. For now lets just get the basics mastered.

I tune with 1/3 octave bands, so that's what I'll describe. Click EQ Filters.
You can set up a set of blank filters, but only 20 (not 31). For now I'd fill in 160, 200, 250, 315, etc all the way to 12,500 Hz, set the type for each to PK, and the Q for each as 4.31. Then save it by clicking the little disk.

Now you can add or cut gain at any of the filters, and see the result directly on the graph. You should have some bands that you don't need to alter at all, and you can reassign the frequency on those to 100, 125, 16,000 etc as required so you can cover the areas that need eq.

That's a just basic walkthrough using 1/3 octave bands. There's more advanced things to think about and work with, like EQ'ing past the crossover frequency, employing mass cuts or boosts, identifying and working with non-minimum phase areas, determining actual sub/mid crossover point, using the overlays screens for balancing predicted L/R response, etc.

There's enough to keep you busy for a long time. Have fun!


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## therapture (Jan 31, 2013)

Yes, that helps, doing that multiple times is the fine tuning of the process it would seem.

I just had a eureka moment from reading your method, I was just entering the values into my mid crossover, not even touching the sub eq! I am an utter noob haha. What level should by sub remote level control be set to for the intial measuring? Halfway?

I'll report back my findings after a few sessions.


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## mojozoom (Feb 11, 2012)

Honestly you need the sub off until you hit the target curve (including crossover cutoffs) with the mids, one by one.

Then EQ the sub to the target curve inclusive of LP filter.

At that point you should be able to turn everything on, run a sweep, and determine if the sub level needs to go up or down to get it to line up on your target curve along with the rest of the system.

Once that level is set, you need to step thru small TA increments (like 1" at a time) on the sub and plot out multiple sweeps to determine the best phase relationship of the sub & mids. I call it the "Rainbow". You'll be trying to maximize the SPL at the crossover frequency, as well as maintaining the best levels possible on either side of the crossover frequency.

Once that's done, you may need to go back and check the FR of the sub versus the target curve as it may need a little tweaking. Then you'll need to check the overall relationship of the whole system again as some additional mass cut on the sub may be required to line back up with the target curve.


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## evangojason (Feb 12, 2010)

Your talking about your 3sixty3 remote right? I set mine to 0 when tuning. I find its the easiest way to get back to where I had it tuned.


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## therapture (Jan 31, 2013)

mojozoom said:


> Doing one at a time is the best. It'll be alot easier since you are running passive as well.
> 
> 
> 
> There's enough to keep you busy for a long time. Have fun!


I'm running active, or it's passive since my tweeter on the Imagine is in co-ax mode?

Thanks to both of you guys, I might just get something done with the stuff both of you posted


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## therapture (Jan 31, 2013)

mojozoom said:


> *I tune with 1/3 octave bands, so that's what I'll describe. Click EQ Filters.
> You can set up a set of blank filters, but only 20 (not 31). For now I'd fill in 160, 200, 250, 315, etc all the way to 12,500 Hz, set the type for each to PK, and the Q for each as 4.31. Then save it by clicking the little disk.*
> 
> Now you can add or cut gain at any of the filters, and see the result directly on the graph. You should have some bands that you don't need to alter at all, and you can reassign the frequency on those to 100, 125, 16,000 etc as required so you can cover the areas that need eq.
> ...


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## mojozoom (Feb 11, 2012)

On the filter setting, I've found they don't need to say "Manual" for them to be manual. You can leave them as "Auto" and it'll still work. I struggled with that a liitle as well IIRC.

I'm sorry - I just figured you were running passive due to the coaxial mounting. Since you are active you can run sweeps on the mids and the tweets separately, and enter the HP and LP crossover points for each into REW so it tailors the target curve for you accordingly.

You can manually adjust each band to bring the Predicted curve in to match the target, or you can let REW essentially auto EQ it by using the Filter Tasks menu and selecting Optimise Gains. Since you can only enter 20 filters to start with though, you probably need to select the octave bands that best cover the range of your driver. I use 50 thru 4000. After you Optimise Gains once, some of the filter will be unused, then you reassign them to the top or botom of your range (like 40, 5000, and 6000 Hz on a mid) and Optimise Gains again.


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## therapture (Jan 31, 2013)

So, after I hit the EQ Filters button and it generates the chart...that is what I use to adjust my bands, or am I supposed to manually adjust the gains to make the curve come inline with the target response?

I guess I am missing something fundamental, is there a total noob guide for REW dummies somewhere?


edit: apparently if I adjust the curves to come inline, all the gains would end up at zero which can't be right.
I see I can manually set my 1/3 bands in the EQ chart...as well as Q?


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## therapture (Jan 31, 2013)

I give up. I am just frustrating myself and I might break something.

I understand level matching completely.

I understand I need to get say, the 800hz band to be equal loudness at my mic/head position. 

What I don't get is what the F-K to do with the chart it generates, since it just makes a slew of freq settings like 101, 131, 146, 149, etc. I don't see the relation to the 1/3 octave EQ my 363 has, or how to figure out WHAT cuts/boosts to make to those 1.3 bands.

Seems it would just be easier to use a spl meter, play the tones you want to balance, and set eq levels for that band to be equal at the given position.


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## therapture (Jan 31, 2013)

I just went and listened to my rig, used some pink noise, spectral ranges, IASCA cd test tracks, and real music, to verify that I have a very well defined center image, no smearing as freq ranges go up or down. I have spent weeks and hours using my ears and test tracks, and I am convinced I have a very solid setup. Whether it's flat or not, I guess I don't care, it sounds damn good right now. This is my baseline setting and I backed everything up so I can revert to it.

I want to mess with REW again and I have a huge interest in getting it to a true level balanced state, so I can play around with some house curves.

Right now I am just frustrated and tired of trying to muddle my way around, thanks to you guys for helping me, I will mess it with more later, just not today I don't think. I have spent 3+ hours with it this morning...ugggg...

Attached is the response as it is tuned now, using Hotel California as the source.


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## sqnut (Dec 24, 2009)

therapture said:


> Seems it would just be easier to use a spl meter, play the tones you want to balance, and set eq levels for that band to be equal at the given position.


That would work fine. I know guys who compete and finish top 3 in class, and set L/R balance like this


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## evangojason (Feb 12, 2010)

The 3sixty3 has parametric eq. So band 1 on the eq is 20hz I believe, click on where it list the frequency, (20hz) and type in the frequency of your first filter. Then do the same for gain and Q.


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## therapture (Jan 31, 2013)

evangojason said:


> The 3sixty3 has parametric eq. So band 1 on the eq is 20hz I believe, click on where it list the frequency, (20hz) and type in the frequency of your first filter. Then do the same for gain and Q.


*light bulb goes on* thank you

I'll report back later.


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## therapture (Jan 31, 2013)

I would say I have found some success. Now I am starting to get it. 

It takes a bit of time to measure several times per side, average them, then generate the settings. 

Once I set the three eq plots into my dsp, and listened, I found a couple of big things.

1. My midbass/midrange cleaned up hugely. Everything got alot crisper. I lost some deep midbass but the impact has been retained. I need more testing, but it is making my old eq curve sound a little dead and muddy.
2. The upper end is much more present! As in , damn, it got alot stronger, too strong for me. I am using andys housecurve and it's just too bright for me. Flat sounded terrible, no thanks.
3. I lost some of my focus in the high end, say, 7k and up? The right tweet is too strong now and pulls the tssst tsssst sounds to the right, smearing, so I will need to hand fine tune, but I want to re-do all of the measuring and eq generating several times to see what is going on before I go chasing TA and levels.
4. I see that the averaged plots are showing a stronger response on the right, giving me the trouble (see #3).
5. TA seems a bit too far left, so some of the upper midbass is at my right knee and needs to move over ~4-5 inches.

I want to try hanatsu's curve next, since it seems to be a fair amount "beefier" up to 600hz. I listen to alot of electronica/edm/idm/psy, with a bit of rock and vocal stuff thrown in, and I am want a stronger midbass response akin to my baseline eq.

Here's my current measurement after 2 sessions of recording and generating eqs for my 3 channels (left, right, and sub).


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## evangojason (Feb 12, 2010)

Looking good! Any more questions just let me know. Using the same RTA and processor helps.


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## therapture (Jan 31, 2013)

evangojason said:


> Looking good! Any more questions just let me know. Using the same RTA and processor helps.


Seems my TA is setting the image way left, I am gonna run a few measurements and let it keep working the target curve a bit.

I am headed back out to the garage for a session, I want to look over and check some things, also seems like my left mid is way too bass heavy.

Sometimes the 363 does some weird things like forgetting to save the phase setting on the right mid...and I have been known to accidentally set a band wrong and give some boost where I didn't intend to (beers cause this to happen apparently).

Even scratching the surface, the system is improving upon my "ear tune" settings.


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## evangojason (Feb 12, 2010)

How did you set up your delay?


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## therapture (Jan 31, 2013)

I last set delay by path length, tested for proper phase, and then fine tuned from there via xover and eq. My baseline dsp setting has a very strong center image after weeks of eq work on balancing, so I just used that setting for the REW plot.

The baseline curve is pretty dull sounding though in comparison, with a heavy midbass and flat upper end. 

I am basically starting over on my eq curves, I took several measurements last night late, of all 3 channels, using a flat eq as a reference and will get some of those eq plots set this morning. I was suspect of my methods of using the mic and wanted to make sure I had good date for the program to use.


edit: I find it easier to get my data inside my garage, then bring the laptop inside the house to generate the curves for each channel, then I just list them (or print them) on paper and then go back to car. The laptop is clunky for use inside the car. Also it gets kind of warm inside the car with a laptop dumping heat, not to mention my 6'3" 230lb heater haha.


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## mojozoom (Feb 11, 2012)

rapture,

The graph you posted is using a 20 db axis resolution. With the graph limits settings so coarse, it'll be hard to see the details. I try to use 5 db divisions for tuning and posting, and 2 db for fine tuning and R/L level matching.

If you could, spend some time messing with the Limits setting. It'll really help us see the detail of what's going on.


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## therapture (Jan 31, 2013)

Well, I am still making progress. I used last night's measurements to create some plots. 

* I got to a better tune than I had before, in just 2 days of work, than weeks of "by ear" tuning accomplished.* Thanks to ALL of you guys that helped!



My method, this is based on the hanatsu housecurve:

1. I used correlated pink noise for measuring response, with my remote sub level at -20db. I ran each channel by itself 3x (RH, LH, SUB), averaged, then smoothed via 1/6 octave. Saved the data to the pc for later use.

2. I then created a couple blank EQ filters based on 1/3 octaves from 50-10,000, then from 10,000-20,000. Also one from 20-300 for the sub.

3. I opened those blank filters and told REW to optimize each respective channel to the target curve, then I had a nice setup of EQ bands that fit just right into the 31 band parametric eq, from bottom to top. 

4. I had to level balance BY EAR those upper ranges of tweet, the 2k to 6k range, since the right was hot again. It was minimal though.

I suppose I should take new measurements of the system response and then each channel individually. Then work those back into REW for fine tuning?

Some minor TA tweaks to bring everything back in line, and the soundstage has moved up a bit as well. I only had to do a minimal fine tune on the 2k-6k range to quieten down my "hot" right tweeter. In the Imagine manual it states reversing polarity at the tweeter can soften the output, quite honestly I don't have it recorded where it ended up yet. I may have to pull the mid and see...anyways...

I'll be testing for a couple days with real music. I'll post my response chart in a bit.


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## therapture (Jan 31, 2013)

After some listening on sunday and this morning before work, I found the right side to be way too strong overall. I made a small TA adjustment that was beneficial. But that overpowering right side, I knocked 1.25db off the right gain just to ease it up. I knew I had a problem, so I wanted to make some measurements. I ran several runs of each channel and then averaged them, then smoothed 1/6. 

Now, I can see in the chart that the right side was way overpowering the left! 

So, I took those measurements and re-ran the eq to my 1/3 filters. I see that the right side is getting some cuts and the left side, some gains So it looks like my measuring is maybe getting better or the curve is getting refined. Also the dip at 63-65 hz for the sub is being reflected in the newly refined sub eq settings.

I seem to have a decent center but it was being pulled hard right by sheer volume, and I think making the image smear a bit.


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## therapture (Jan 31, 2013)

1. Not sure what to think about that weird sub plot, I guess from @150 on up that is...background noise?

2. Right mid was overpowering the left from 150-2500 hz, no wonder it was so loud, and this is AFTER cutting the entire right response by 1.25db.

3. I see lots of meat at 90hz, where the sub and mids cross, that would boost response there even more? The mids are driving pretty hard in the midbass and the Imagines are showing off a little haha. I think I want to tone that down a little, but I want to retain the punch. Maybe cross the sub a bit lower as well, it's at 80/24db? The mids are at 85/24db, or maybe I should raise the mid a bit...

I will load the new plots tomorrow and get a listen session in. The learning continues.


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## sqnut (Dec 24, 2009)

therapture said:


> 1. Not sure what to think about that weird sub plot, I guess from @150 on up that is...background noise?
> 
> 2. Right mid was overpowering the left from 150-2500 hz, no wonder it was so loud, and this is AFTER cutting the entire right response by 1.25db.
> 
> ...


1. Cross the sub and mids lower ~50-60hz. Put the sub on a steep slope, 36db or higher. Do not underlap or overlap the sub and mids. Use the eq on the sub/mids in the 60-100hz range so that you have a smooth transition. Go by how it sounds.

2. Cut the right mid by ~5db all the way from 160-2.5khz at 1/3 oct intervals.

the 3-4khz range needs to be 4-6db lower than at 1khz. 10-12khz 2-3khz lower than 1kz. You can roll off the response past 12khz. These are guidelines at best, see what works best in your car/install etc.


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## Hanatsu (Nov 9, 2010)

therapture said:


> After some listening on sunday and this morning before work, I found the right side to be way too strong overall. I made a small TA adjustment that was beneficial. But that overpowering right side, I knocked 1.25db off the right gain just to ease it up. I knew I had a problem, so I wanted to make some measurements. I ran several runs of each channel and then averaged them, then smoothed 1/6.
> 
> Now, I can see in the chart that the right side was way overpowering the left!
> 
> ...


For a good center image, left and right curves should be within 1-2dB of eachother on an overall basis. L/R EQ affect center mostly above 1,5kHz, but it's pretty important even from 800Hz+, below that you'll center with T/A. 

Try bring down the red curve by 5-7dB with a wide Q (~1 or below) centered around 700Hz. Then bring both the red and blue down by 4dB (~Q 2.5) centered around 1100Hz. 

- Bring down 6kHz -3dB ~Q3 both ch
- Bring down 13kHz -3dB ~Q3 both ch
- Level out the differences at 5kHz, lower "blue ch" by 2-3dB with a Q of 3-4 or so.

When that's done you'll have a good baseline. Tune the rest by ear. Just fiddle with the EQ at each band 2dB up and down, you should hear the center change for better or worse.

Btw, be careful in the area 120-250Hz. Avoid peaks in this area! Mids usually sound crappy with too much energy there.


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## therapture (Jan 31, 2013)

OK, I started fresh with a flat EQ. I took 3 measurements of each driver and then averaged them with 1/6 smoothing. I then let REW do it's own number of EQ bands instead of trying to force a particular number. I generated the plots to the original hanatsu curve, it's a bit bass heavy but I am an old basshead working my way to the SQ field so, I'll work on my own later 

Here is the measured response. Funny, the RH (red) side seems weaker than the left up high, atypical of what I have been seeing. Not sure about that but I ran the measurements an extra round to be sure. I also listened to the flat curve in the car for a few minutes, with just my normal TA applied, not too bad. What I would call a decent stereo.

I am fixing to go to work on the curves in a bit.


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## therapture (Jan 31, 2013)

SUCCESS. My initial impressions of the REW generated curve using Hanatsu's housecurve as a target:

1. The massive midbass is trimmed down, not what I expected, but MUCH MUCH cleaner and crisp from bottom to the top.

2. The center image is right in front of my steering wheel, but from jacking around with it, I know my base is very close, so I assume it is a level balance thing in the 800+ range.

3. The REW EQ generation only generated 10 bands to adjust on each side...and nothing past 7k. The sub plot was a bit more detailed, with about 9-10 bands just from 20-150.

I went to work, by EAR again, with my 1/3 pink noise and spectral bands from the IASCA and Autosound cd's. I made some minor 1-2 db cuts and boosts on several bands all the way up to the 15k range to line up the frequencies in the middle of the dash...this fixed the majority of my TA issues and I only needed a minor .1 ms change to get it straight. 

I think I had been doing two things wrong with the EQ, one was stacking one tune on top of another, and totally undoing the changes I had made, with the new changes caused by re-assigning bands to new frequencies. The other was chasing too many frequencies, thinking I HAD to adjust every single band! I was basically ruining the EQ curve and deviating majorly from the target.

Results? The midbass is tight, the "snap" is there, but the mids are not appearing to work as hard as before, and the resulting SQ increase was unexpected but welcome! Everything is CRISP and DETAILED. The "s" sounds (sibilance?) are improved. I am not getting the "hollow but hard" midbass anymore, and it just sounds more balanced and natural, especially on drums as they pan across the set.

The subwoofer plays the lows with authority, but not getting boomy at any point. I guess I got it playing flatter across it's range, removing some peaks. Detail is abundant in bass lines and it never get gets muddy.

I have not measured the response again, and I won't for a couple days, I just want to listen to it for a while and get a wide variety of music in. I just took a drive around town and I am really, really liking the new sound. I may need a bit more midbass and sub for highways speeds, any suggestions on what ranges to boost a wee bit to cure that?

Again, thanks to all of you guys for helping me remove some of my noobness


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## Hanatsu (Nov 9, 2010)

Sounds great 

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## therapture (Jan 31, 2013)

After some listening tonight, I am further convinced I have found a solid base line to work off off. This tune makes the previous attempts at EQ'ing, taste like tough beef jerky and a dry mouth. They sucked. I switched back and forth a couple times, and it was ugly lol.



-My soundstage has raised itself nicely across the dash and sides don't droop as much. 
-Vocals have cleaned up, especially on the "sssss" and "t" sounds.
-Midbass is cleaner and less "bassy" while retaining impact and presence, and I dropped them down to 75hz @24db. 
-The subwoofer is integrating even smoother than before, after crossing it down to 75hz @24db, and I am starting to see what having an "articulate" sub means. Also, the sub is playing flatter and less peaky.
-The "up front" bass image even moved up in the dash, like I have a small woofer up front (as long as I don't get nutty on the sub level).
-The stability of the center image is much, much improved and more focused. I can move my head a couple inches to each side without ruining the image.

Finally going active is really paying off. I can't imagine my tunes without it now. It's like Natural Light against Sierra Nevada Torpedo IPA. I'll drink the former in a pinch, but if I am paying for it, it's gonna be the latter!

I'll update in a few days with some measurement data.


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## therapture (Jan 31, 2013)

Update, still using hanatsu's housecurve:

I have no data measured yet, I will get to that tomorrow evening. But I have been listening to all of my music for a couple days, not adjusting anything dsp wise, and here is what I am finding.

1. The midbass, while crisp and clean, is a bit less than what I want. It is drastically reduced from my previous attempt.

2. The subwoofer is also "toned down" a fair amount, I find myself turning the remote level up more, on older music, I have it all the way up.

3. level balancing is solid, I sometimes see a bit too much on the right, but then a different song will be a bit too much from the left, I chalk this up to...the way the music is recorded. Correlated pink noise bands sound very centered fro the bottom to the top.

4. Image is tight, but maybe a tad too far left. And I mean a small amount. I think I can cure this with minute .01 adjustments.




NOW, a big question. Since I now have a solid level balancing to work from, if I want to tune for more midbass, sub, whatever..or if I just want to tune the existing response to more closely hit the target curve...should I take the LH-RH averages and tell REW to match that? Wouldn't that give me say, a single setting that I need to implement on both sides? Ex. Say that 800hz is balanced L-R, and I run the average of both sides, and REW suggests that I cut 800hz by 2db to hit the curve. That means I cut 2db on BOTH sides at 800hz...?

And hanatsu, being that this is your curve...if I want a bit more "punch" from the midbass...what EQ ranges do I target?

And I won't change anything until I get some more solid measurements of the existing setup. This is my baseline right now, so if I goof something up, I can easily revert.


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## therapture (Jan 31, 2013)

Wow, I don't know what to think about this result. I have been listening to this for a couple days, and I finally got in today and recorded a few runs. Each channel 3x, averaged, and 1/3 smoothed. I'll say that the system is very clear, maybe a little bright on S and T sounds. It's is definitely "bright enough". I did lose some midbass punch, not sure that's an issue. The resulting curve AFTER using the REW generated filters, plus a small amount of level balancing from me, is WAY CRAZY. I think I need to start over or something....or I did something utterly wrong.

red is RH...why are both sides so far from each other, it appears REW did a terrible job of matching the target...

sub is yellow (duh) what is that weird rolloff for the sub at 140hz+ ?


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## Hanatsu (Nov 9, 2010)

Way too much energy in the 500-2000Hz area... down with them 10dB or so. To get punch in the midbass you might wanna look at 80-110Hz. The "snap" however, might actually be much higher up - in the midrange. The sub's curve looks pretty normal, they often roll off pretty steep at some point. 

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## Hanatsu (Nov 9, 2010)

Also try to get a smooth transition between 100Hz ---> 200Hz. 100Hz should be 6-8 dB louder than 200/250Hz then a slight rolloff towards 1kHz or "flat" if you prefer.

Bring down 7-9kHz to decrease the sssshhhh sounds 

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## therapture (Jan 31, 2013)

OK, I tuned it, by hand, using the previous plots. It got a bit better, and it sounds a bit better. But I can't seem to make the 1500 spike and the 4500 dip go away. The 1500 got better, maybe I need to cut some more there on both sides?

This second run is with me in the car, locating the mic on the left and right side of my head, under my chin pointing up, and on my head facing forward and down a bit, for 4 measurements each side. I regained some of the midbass, and I seem to be good there.

purple = right side.










I am going to do one more session, trying to flatten the curve. Thanks for the tips. More to come. I am about out of beer, so when that happens I will be done for the evening as far as tuning.


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## therapture (Jan 31, 2013)

Well, I ran a third tune, saving all 3 in order to my dsp presets. The 4500 band, I tried more boost, and it got so bright I think my neighbors heard the tweeters. So back it went. 1500 came down nicely, but sounded flat and lifeless.

To be honest, each iteration got duller and duller (high end flat, dead, boring) as I tried to tune out the over brightness. I like the FIRST one the best, jagged as it may seem. It's still a solid baseline so I will keep that.

The second tune has a touch more midbass, which I like, so I think I will just work on this one and bring back some of the highs I flattened too much.

The third iteration I just measured, I accidentally tossed the records before I saved them out of REW, but screw it, I don't like the sound at all so it doesn't matter.

Time to just listen to it again for a couple days. I am tired of tuning.


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## Hanatsu (Nov 9, 2010)

Be careful with boosting bands. A 3dB boost require twice the amplifier power at that specific frequency, might put strain on speakers as well and if the dip is caused by cancellations it won't do much good anyway - might just add distortion.

Post a 1/24oct smoothed plot, decay and distortion plot if you feel like it 

Other issues will show up there.

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## mojozoom (Feb 11, 2012)

therapture said:


> This second run is with me in the car, locating the mic on the left and right side of my head, under my chin pointing up, and on my head facing forward and down a bit, for 4 measurements each side.


I'm thinking your averaging concept here might be a problem. Unless your right ear can move itself around the left side of your head or to your chin, that is.

I'd recommend four samples: straight ahead, look at left mirror, look at right mirror, then straight ahead again. This will weight your average to the straight ahead positions, which is how most of your listening is done. I was suprised at how different the two forward facing measurements can be after just turning your head a few times and then back to what should have been the same position.


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## sqnut (Dec 24, 2009)

There will be a point when you will let go of REW and dialing in house curves. Beyond this you are using your ears as the measuring device and playing with the eq to dial in tonality. 

If you have the vocalist at stable at your rear view mirror, each instrument is located at a fixed spot i.e. no smearing and you can't locate your speakers while hearing the music (listen with your eyes closed), if you have these then your L/R balance is good and your speakers are in phase. It may still not sound right but your measuring days are numbered and its time to go by ear. Sure you will get lost along the way and things will get messed up, but you will have your baseline to come back too. Stick with this and over time the baseline itself will get better. 

Let's say you want more in the mid bass region. How does it sound currently? Is the mid bass weak or is it dull? If it's weak try boosting a bit in the 100-160hz region. Try boosting 100/125/160 individually see how each frequency changes the sound. Instead of boosting 4db at 100, try 2 db at 100 and 1db at 160 and see how that sounds. 

If the MB is dull, try cutting some at 200-300 see if that helps. The mass of MB is in the 80-300hz range but the impact and snap is in the harmonics. So, if 1-2khz is set too low the MB will sound dull. 

The point is while measuring and REW etc is good for setting up the basics, you will eventually have to venture out and use the eq manually to get the right sound. To do that you need to understand what boosting and cutting each frequency does to the sound.


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## Hanatsu (Nov 9, 2010)

Indeed. When you're done with measurements you do the rest by ear. At this point it should be fine tuning only though.

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## therapture (Jan 31, 2013)

Well, I have got to say, I have ran into an unexpected...result. Time to try some more housecurves, now that I seem to have a basic grasp on HOW to measure (thanks hanatsu) and thanks to all of you guys that have been nudging me into the right direction.

I was using correlated pink noise to RTA. And I was using some...weird...mic positions. Now I know to use the sweep in REW for my initial runs. I also have my mic position more accurate and repeatable, more closely matched to where my ears/head is in the car.

I have spent the last several hours measuring, tuning, re-measuring, starting over, etc. And one thing that HAS happened, is I have found some consistency. I seem to get the same result after 3 different measurement runs, REW EQ setup, and the results are actually quite different from what I had before changing my methods. The level balancing is quite decent for an initial run, and in REW the target and predicted curves are lining up nicely with less EQ than before (about 15-16 bands). 

One thing...the hanatsu housecurve is BASS/LOWER MIDBASS HEAVY.  Too much for my poor Imagine 6.5's + electronic music, at the level I like to listen at. It has a nice sound at LOW volume levels (very "fat") but is too heavy as the volume rises. I want a bit more "snap" and "kick" to the midbass, just not so low, right now, my Imagines are playing so low and deep I can listen without the sub and get oodles of bass, right to where they start sounding like ass from being overdriven. Even crossed up at 85-90 hz they are delivering prodigous low end but I still need more high end. The upper mid/highs are very subdued, and I need to figure out how to tune it up to where I like. I need about 50% less bass and 50% more mid/treble. I think I will try his newest curve, as well as the Andy W. housecurve again. Now that I have some basic skills started, I think I will find a whole new set of results with those curves. Previously, I did not like the Andy W curve, it was super bright, flat in the midbass, and I hated it, now of course I know, my method of measuring and tuning was at fault and I doubt I heard anything it was supposed to be.

So here I am again, at the beginning. I sent hanatsu my fresh set of flat EQ measurements/sweeps for him to take a look at, but I think I am going to find out the same result if that curve is the target. I am going to load up his new curve and generate some plots, to see how much different it is from this one.

The saga continues! At least I am finding out what I like to hear, and I think it is going to be a bit outside the "pure SQ" curve. I listen a bit louder than most I think, I have a semi-noisy car (exhaust, 6.0 V8), and I probably have some hearing damage on the high end from multiple 15" subs back in my "roaring twenties", so I need a bit more "sparkle".


EDIT: I took my base measurements, re-ran REW for each curve, the Andy W. and the hanatsu-2, I am beat, so I will load them into the filters tomorrow. Maybe then I can post graphs of all three tunes, but not for a couple days, I need to do some more listening and to be honest, I am tired of tuning, I need a break


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## Hanatsu (Nov 9, 2010)

Don't use it initial curve I made. It's too hot in the lower regions when you're listening at higher volume as you said. I used it because it sounded good at moderate volume while driving. Try the new one I made or the MS8 curve, quite similar. Just slightly different preferences 

Now when you're using sweeps you can check distortion, excess group delay and decay plots as well. They are great features to troubleshoot your system.

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## Hanatsu (Nov 9, 2010)

Ah I'll take a look at your measurements later 

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## therapture (Jan 31, 2013)

I'll post some info tonight, I have made some huge success in the last two days with my home grown curve! I had a huge post typed up last night and accidentally wiped the page....!!!

Hanatsu, your curve #2 is my foundation but with some added data points and EQ increases. I'll post it as well tonight after work.


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## therapture (Jan 31, 2013)

UPDATE:

I have refined my own home grown curve, after listening to the system for a few days with a variety of music. Not worrying about what the curve looks like, but letting my ears define the overall tonality, while using test tracks to make sure I keep balance correct from left to right. The system is coming alive and sounding very good.

My curve looks "bright" compared to hanatsu's and Andy's..but whatever is going on, it is good. I spent some time in the hotel room Saturday evening refining the housecurve and plugging it into REW to see what the predicted response would be, and generated some EQ settings to try.

I got to set the 3sixty.3 earlier this evening and do some fine tuning, then some listening. Wow. I am actually jazzed! The sub is clean but powerful. Impact is there from the mid drivers, and I FINALLY got my tweeter balance correct. The image is much more stable and centered, no wandering. Vocals are smooth and crisp. Interesting, to get it smooth and balanced, I had to cut ~7-8 db @1.375k and it made a HUGE difference in the stability of the image! The sub is staying clean, articulate, and I can easily get what I need with just a couple clicks up or down on the remote bass level of my DSP. I did have to retune to a 102db level in REW from the baseline of 100db so I could get some range out of the remote level without having to max out the knob on older music.



I still have not ran sweeps of this setting, but I will tomorrow night.

My home grown curve, borrowed a bit from the sub section of hanatsu's 2nd revision:

*******************************************************

20 10
25 12
33 10.5
40 10
50 9
60 6.5
70 4.5
80 3.5
90 2.5
100 1.5
150 1
200 1
500 2.5
800 2.5
1200 3
1500 2.5
2200 2
2500 2
3000 1.5
3500 1.5
3800 1.5
5000 1
6500 1
9000 1
10000 1
12000 1
15000 1
20000 .5

This is the target curve I made (blue, duh), just using the un-EQ'ed left and right averages as an indicator of where I was. Not really understanding what the weird dip at 125hz and 4.5k are an indication of. If I try and boost 4.5k to level it out, it's way too harsh and bright. Cranking on 125hz gets too muddy and sloppy as well.


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## crazhorse (Mar 9, 2010)

Just got my mic today..... so just getting started with REW.... been going over the threads, understanding some things and not so much others. Heres a eq filter REW suggested after doing some quick measurements. On the suggested freq there are a bunch at the 100 hz area, do you just adjust the closest freq to get closer to the curve or ?
Also on the measurements of the drivers, I'm running HAT imagines active... with a sub, do you measure each as in left side tweet, and mid or together left tweet/mid and right tweet and mid. Equipment is a alpine ixda305, rf 360.3 alpine pd5 amp, hat imagines and a jltstealth box (has a 10" sub in it)


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## therapture (Jan 31, 2013)

Sorry, I need to merge two threads...can this be done?

http://www.diymobileaudio.com/forum...on/149484-freq-response-big-dips-cause-2.html


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