Audiophiles: Touring factory EQ curve doesn't change with volume!

FaintReality

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@josby - how did you connect your laptop to the OEM head unit?

I was going to take some measurements of the stock ex head unit, but there is no auxiliary input. Will a male to male USB cord work?
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josby

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@josby - how did you connect your laptop to the OEM head unit?

I was going to take some measurements of the stock ex head unit, but there is no auxiliary input. Will a male to male USB cord work?
No, I don't think so.

I used Room EQ Wizard's WAV file generator to create files containing pink periodic noise ("Pink PN") then put them on a USB stick and played those while using REW to measure. Make sure the sequence length is the same as the FFT length used when measuring (read the REW help file on Pink PN).

I connected a Honda speaker plug adapter into the factory connector, then clipped the wires into alligator clips on a cable I made. The other end of the cable has a 1/4" TRS tip on it that I can plug into my USB sound card's input.

The catch with that is the potential peak voltage output on the speaker connector is a lot higher than my sound card's max input voltage, so I knew I'd likely end up with clipping and maybe even fry the sound card. A voltage divider circuit can be used, which I tried first, but later realized that I could generate a bunch of Pink PN sound files at lower dBFS levels. I made one at -80 dBFS, one at -70, etc. That way the peak level in the track is not high enough to produce too high a voltage to the speaker wire even when the headunit volume is up high.

So I'd start measuring with the -80 one, then go to -70, etc. until I saw the red clipping indicator in REW light up, then I'd back down to the previous one and use that one when measuring that particular headunit volume level.
 
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FaintReality

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Ok, so I created a Pink PN wav file and saved to my SanDisk 64gb Cruzer Glide and headed to car. Plug in both front and console USB port with no luck. Thinking maybe it only reads MP3's, I jumped online and used a free converter, saving a copy as an MP3 format. Car still won't read my USB flash drive. Now what?
 
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Seems to be a somewhat common problem with this thing not reading some flash drives. I haven't had the problem so I'm not sure how to solve it, but check this thread: http://www.civicx.com/threads/usb-flashdrive-wont-read.5095/

I think it may be more of an issue with larger flash drives, so if you have another smaller one, that may be the easier thing to try. The one I used is 16GB.
 

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I'll try a smaller flash drive. Was it able to read the WAV file or did you convert to another format?

* edit - new, smaller flash drive did the trick. Played wav file from both USB ports.

Thanks josby
 
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Well, it's possible the LX/Sport radio may behave differently than this - I haven't measured one and it's definitely a different unit than the Touring. So take this with a grain of salt. But if I had to bet, I'd guess it will behave the same.

Don't think of it as the bass decreasing at higher volumes - think of it as bass increasing at lower volumes.

I would calibrate it around volume 30-35. Better to go too high than too low. You could calibrate it at 40, but the signal level of the calibration track is probably at the maximum, while the level of most music won't be, so calibrating at 40 would probably waste some headroom. Calibrating at anywhere from 29-40 will give the same sound profile, just with a lower max volume if calibrated at 40, and the possibility of distortion at volume 40 if calibrated at 29.

Once you have that calibrated, the effect will be that at volumes 29-40, your amps will be getting exactly the signal that's in your music. Below volume 29, the bass level will be slightly higher relative to the rest of the music. Down to volume 20, the increase is pretty slight, though. Below volume 20, the increases get bigger. At that point your music should be pretty quiet. At that quiet level, the extra bass will make things sound better.

So basically you want your amp gains set such that your normal driving-alone-and-jamming-to-a-song-you-love volume position is in the 30's, and your it's-dark-and-I'm-lost-so-I-turn-the-music-down volume is somewhere in the teens. :D

So, I was finally able to connect my laptop to the JL Fix86. The eq curve was kinda flat from the stock radio at Vol 30. However, my speakers are super bright and the doors suck with the mid bass, so I had to EQ the crap out of it. Didn't spend much time with it, because the battewry died on my lap top. But, I'll post pics of the eq curve pre and post Fix86 so you can see the difference.
 

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@josby

Alright, I recorded multiple pink PN full range times at different dBFS levels. For the attached graph, all were taken with the -24db tone with the exception of the 'volume 5' response which was tsken with the -12db tone do to the noise floor level.

Basically, I played the tone, turned volume to 5, took RTA measurement and saved. Then the same at volume 10, 15, 20, 25, 30 and lastly volume 35.

When looking at graph, all look linear and have the same measured spl gap across the full range with the exception of volume 5 which I think is due to the inaccuracy as it's too close to the noise floor level.

Do you see any flaws here? Safe to assume the EX sedan has no volume dependant EQ adjustments and we can safely tune at any volume level and retain full control of stock HU & steering wheel volume controls?

* disclaimer - all measurements were taken from passenger seat with the mic held in place between top of seat and bottom of head rest. Fader and bass/mid/treble were set to middle and SVC is set to off. For those of you trying to tune, do not use these frequency responses as they are not accurate and were only used for comparisons against various volume levels with all else remaining the same.

Honda Civic 10th gen Audiophiles:  Touring factory EQ curve doesn't change with volume! 20170809_122820


Honda Civic 10th gen Audiophiles:  Touring factory EQ curve doesn't change with volume! OEM DSP on
 

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Upon further inspection when overlapping graphs, it looks like the built in dsp does indeed cut the lower frequencies when volume is raised.

In the graph below, I overlapped volume 15 (red) and volume 35 (blue), and you can see there is a ~3db cut centered at 75hz.

Honda Civic 10th gen Audiophiles:  Touring factory EQ curve doesn't change with volume! Volume 15 vs 35
 

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Upon further inspection when overlapping graphs, it looks like the built in dsp does indeed cut the lower frequencies when volume is raised.

In the graph below, I overlapped volume 15 (red) and volume 35 (blue), and you can see there is a ~3db cut centered at 75hz.

Volume 15 vs 35.jpg
Where in SoCal are you located? Maybe you can help me tune my car with your RTA? :)
 


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Where in SoCal are you located? Maybe you can help me tune my car with your RTA? :)
I'm out of the AV about 30 miles north of magic mountain. Today is the first time using the REW software so I'm just learning as I go and am no expert. I will be starting my install soon and will have much more experience when I start tuning my setup.
 

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The red is the EQ pre JL Fix86 DSP and the orange is post. (For LX/Sports models)
Honda Civic 10th gen Audiophiles:  Touring factory EQ curve doesn't change with volume! CivicJLFix86
 

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The red is the EQ pre JL Fix86 DSP and the orange is post. (For LX/Sports models)
CivicJLFix86.jpg
Looks like a pretty big cut. How does it sound? How about the volume loss, still plenty loud? Does the fix-86 offer different house curves or just sets the response perfectly flat and then allow tuning to personal taste from there?
 

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Looks like a pretty big cut. How does it sound? How about the volume loss, still plenty loud? Does the fix-86 offer different house curves or just sets the response perfectly flat and then allow tuning to personal taste from there?
There is a tab where you can adjust the EQ for each side (Fronts, Rears, L and R) to taste. The Fix86 does a pretty good job a At leveling thing out and giving you a good starting point - it does get plenty loud.

However, I think my installer is incompetent. There might be some phasing/polarity switching going on with the wiring — my ears literally hurt, even at lower volumes. There's also an extreme lack of bass. So, I haven't been able to tune it right to give a good assessment. But, visually, it looks like the Fix86 is doing its job.

There's another DSP than you can link up to the Fix86 called Twk88. Now, that gives you unlimited possibilities for setting up and tuning your system, hence the name.
 


 


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