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Why does DIRAC completely remove bass response (KEF R3 + sub + minidsp flex)

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Geertidow

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This is the total response of all speakers combined. I figured that is what dirac is supposed to correct.
 

abdo123

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This is the total response of all speakers combined. I figured that is what dirac is supposed to correct.
No not at all, Dirac corrects for individual channels. With a MiniDSP setup you even have to do the bass management on your own.
 
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Geertidow

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MiniDSP thinks differently on the bass management (they say their 2.0 module works really well in a 2.1 system).
By bass mangement do you meen room EQ?
 

abdo123

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MiniDSP thinks differently on the bass management (they say their 2.0 module works really well in a 2.1 system).
By bass mangement do you meen room EQ?

No i mean setting the levels, crossovers and delays between speakers and subwoofers. Dirac in its current configuration can't do that with MiniDSP.
 
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Geertidow

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No i mean setting the levels, crossovers and delays between speakers and subwoofers. Dirac in its current configuration can't do that with MiniDSP.
Oke then I understood correctly. That I have done. No delay in sub and speakers since I have placed them at the same distance (2.50 meter driver to ear) and confirmed by measurements.
 

peng

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Here you see my dirac results, this with no PEQ whatsoever beforehand (XO 90 hz, 18db/oct speakers, 30 db/oct sub).
I still dont know what to make of this. I like the sound of the full range and the 500 hz, but the 300 hz and 100 hz are off.
I used to use DIRAC only up to 300 hz and this was fine.

If you compare it to manual PEQ or no DIRAC, i seem to loose a lot off bass. What am i missing here.
Measurments are at LP using sub, left and right speaker.

I have experimented numerous times on applying PEQ, sub crawls, phase, level adjustments on the sub amp, before, after, or no such adjustments before/after running Audyssey, Dirac and now AARC. There are so many REW graphs on my hard drives, making it very difficult to be 100% sure which is which after a while, but I can tell you in the end, I have concluded that it is not worth doing anything manual. Other than the fun and the acquired knowledge by spending so many hours on it that I now know there is absolutely no point doing anything after than running the RC software by following their instructions to the letter, and then do whatever tweaking the apps allow, run REW to check the results and then sit back and enjoy. Yes, REW graphs may show some minor gain with those other manual adjustments and/or PEQs but the difference would be so minute, even on just the frequency response curve (such as 0.5 to 1 dB) flatter/smoother, I will not be able to hear such difference when listening to music and movies.

Back to your REW graphs, I have never seen anything like that with Dirac in use, but I have never used it with the minidsp+manual PEQ etc., either. I did use the mini/REW/PEQ with Audyssey and had no such bass disappearing either. I went back a couple pages and could not find anything specific about your setup. Can you link to your previous post that describe your system? It seems to me you are using a minidsp flex 2 channel system, and that you are using Dirac Live with manual PEQ? If so, have you tried using Dirac only, with no manual PEQ or any other adjustment?
 
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Geertidow

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As in the original post:

Setup:
Speakers: KEF R3 + Push/Pull subwoofer (10").
Amp: NC252MP for the R3 + NC500 mono for the sub.
Source: MiniDSP flex (balanced) with USB attachted to computer for measurment.
Mic: UMIK-1 (with cal file)
Edit: Crossover: 90 hz with a 12 db/oct roloff for speakers and 30 for sub.
Edit: DIRAC in shown measurements: +4db harman kardan with a slight -1 dB roloff in the higher region (standard starting curtain), full range..

The results you see from the most recent post (today) are from dirac with no peq whatsoever, only an xo. But the correction still seems off. Bass starts late. Full range sounds better than 200 - 300 hz correction. I have never had that before.

Latest measurements done in 2.1 setup using all speakers, mic at MLP
 

tjcinnamon

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I have time alligned the subwoofer and speakers perfectly using req. Impulse response, step and phase are perfectly aligned. Furthermore, xo problems should be worse at the xo region and not over the whole 30 - 200 hz region and should persist without DIRAC. Neither is te case. DIRAC somehow does not even remotely adhere to the target curve the whole section below 200 hz gets pulled down a lot (3 db under the 2 kHz mark). It's just strange that this didn't happen with the genelecs 8030c in the same setup. Luckily the R3 sounds great without DIRAC and some minor PEQ but I would still like to find out why DIRAC seems to completely mess up.
What do you mean by perfectly aligned? Are you saying the delays on the sub flatten the response with the mains in the crossover area OR are you saying that the bass arrives at the same time as the mains?
 

tjcinnamon

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It seems that just restoring default config and reuploading the same filters works.
Apparently there was some kind of software error.
The problem is now that DIRAC does not seem to make it much better after al ;-)
Without DIRAC the curve is pretty nice.
I managed to get away that 80 hz dip by increasing the xo from 60 to 80 hz.
What's your waterfall or spectrogram look like in REW? Betwen calibrated and non-calibrated?
 

tjcinnamon

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I used this method to determine my crossover:
Believe it or not 80 and Large produced the best results with no additional delay applied to the subs!?!?

I went with 80Hz just because it's simpler. My speakers have 2 10" ported woofers per speaker, so large seemed reasonable.

And I use cross correlation time alignment to get my subs to a single time aligned response:
 
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Geertidow

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What do you mean by perfectly aligned? Are you saying the delays on the sub flatten the response with the mains in the crossover area OR are you saying that the bass arrives at the same time as the mains?
I used slow sweeps between 50 and 150 hz with acoustic timing reference and alligning the step, impulse and phase.
+ the sub driver is at the exact same distance as the speakers (coïncidence of the sub crawl method).
So I mean time allignment such as requested by the MiniDSP support crew.
 
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Geertidow

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Geertidow

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It is finally working!
Updating the DSP and XMOS and setting the speaker delay on 2.2 ms did the trick.
Sound is really as it should be although this is still an untreated room.
 

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mdsimon2

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It is finally working!
Updating the DSP and XMOS and setting the speaker delay on 2.2 ms did the trick.
Sound is really as it should be although this is still an untreated room.

The worst part, miniDSP dev team is basically saying I have to allign the sub (already did)

12 years of DIRAC and never has that been an issue. It really feels like an overconfident tech support.
Also since they don't seem to believe me I have really time alligned the sub.

So wait, after all this it was just that you had not properly integrated the speaker / subs? Which was exactly what miniDSP tech support suggested?

Michael
 

tjcinnamon

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So wait, after all this it was just that you had not properly integrated the speaker / subs? Which was exactly what miniDSP tech support suggested?

Michael
Curious, only Dirac with Bass Control does that automatically, correct?
 

mdsimon2

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Curious, only Dirac with Bass Control does that automatically, correct?

That is correct.

Without DLBC I am a big fan of what @abdo123 mentioned earlier in this thread which is getting your sub / speaker crossover to sum correctly anechoically prior to attempting room EQ. Unfortunately this is basically impossible to do with in room measurements but is achievably based on understanding the speaker / sub low anechoic low end response and any delays caused by speaker placement or other things (many active subs have some amount of built in delay due to DSP).

Michael
 
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Geertidow

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So wait, after all this it was just that you had not properly integrated the speaker / subs? Which was exactly what miniDSP tech support suggested?

Michael
No it was the software I think.
I ended up with no delay using the tutorial suggested above and it still works properly now.
The time allignment was something I played around with, but the 0 ms delay gave me the exact same results as 2.2 ms delay.
 

tjcinnamon

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That is correct.

Without DLBC I am a big fan of what @abdo123 mentioned earlier in this thread which is getting your sub / speaker crossover to sum correctly anechoically prior to attempting room EQ. Unfortunately this is basically impossible to do with in room measurements but is achievably based on understanding the speaker / sub low anechoic low end response and any delays caused by speaker placement or other things (many active subs have some amount of built in delay due to DSP).

Michael
I was able to do this with REW and a MiniDSP. Basically align the timing of the subs and mains to flatten that response
 
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