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Hi

I've had a MiniDSP DDRC-24 since April. When I first installed it I was super happy with the performance. Then I lent it to a friend to test out. I recently got it back and remeasured my room response. Something is now seriously wrong. The new correction totally messes with the phase of the sound, sending the image to very wrong parts of the sound stage and sometimes way outside the speakers. Additionally the bass issues are not fixed and in many cases worse than without correction applied.

I tried:
- reverting back to old, known good versions of DDRC-24 software and Dirac live
- using 90 vs 0 degree mic calibration files
- only applying correction from 50Hz to 500Hz
- remeasuring the room response 4 times

Nothing here worked and the 3rd point makes me wonder if something is screwed up with impulse response correction as the issue is still there after i reduce the correction frequencies.

The only thing that gives a reasonable result is loading an old session from when I first got the unit.

The only other variable that I can think of that has changed is that maybe I updated the firmware to the latest (1.14)

Can anyone please shed some light on this issue? Are there any known problems with the firmware or anything else I'm using?

My setup:
Naim UnitiQute 2 -> MiniDSP DDRC-24 -> Naim NAP200 -> Naim Ovator 400

UMik-1 and MacBook Pro (Intel running Big Sur) for measurement and filter generation

cheers,
D.

Do the measurements look sensible, and like what you had before?

Frequency measurements are totally sensible, and very similar to what I had before. The impulse responses look weird to my eyes

Have you compared measurements with Dirac on vs off in REW to see what is going on? 

You're probably best contacting miniDSP support to be honest but the more info. you'll be able to give the easier it will hopefully be for a solution to be found.

Thanks. I will def contact MiniDSP support (are any MiniDSP techs on these forums?). Haven't tried measuring yet but for sure there are phase issues. when a formerly centred part of the image jumps outside the speakers, its kind of a giveaway

yurisequin wrote:

Thanks. I will def contact MiniDSP support (are any MiniDSP techs on these forums?). Haven't tried measuring yet but for sure there are phase issues. when a formerly centred part of the image jumps outside the speakers, its kind of a giveaway

Level issues for at least part of the frequency range could do something like that I think.

Generally it's users rather than miniDSP staff who post on this forum. That's why it's described as 'Community Support' as distinct from miniDSP Support, whch you can contact via the link at the top of the page.

Just for completeness, it seems the problem has been confirmed and is connected to the newest Dirac update:
www.minidsp.com/forum/announcements/1939...-under-mac-osx#56980
A simple fix for now is to revert to an older version. 

My problem looks different and I discovered 2 potential causes: I have an acrylic coffee table asymmetrically positioned between the sofa and the speakers (to the left). When I tried measuring the room again I removed it from this area and also removed the back cushions from the sofa (foe better mic access). This seems to have completely rectified the issue. 

The problem mentioned in the article you linked seems to show a reduced bass response in 2.1 systems. Mine was clear phase issues - not only reduced bass - in a 2.0 system.

thanks for sharing though.
 

Great that you solved it!
The post that I linked shows phase problems everywhere because the summation is not at a constant +3dB, although it is indeed worst for the bass. Thus, I thought this could have been it but good that it was "just" a room problem. It is surprising how a small reflection can totally destroy the sound stage but I also had that many times. 

I didnt mention that I moved the table back after measurement. still sounds great. its just that it was confusing the measurements.