Have you noticed this? Software EQ + ext DAC

[concorde1]

I use the 8 channel Topping DM7 DAC.

With Equalizer APO for EQ on W10 and CamillaDSP for EQ on Linux.

There is this phenomenon I'm facing where, presumably due to ordering of turning on DAC + computer + EQ software, sometimes something seems to go wrong with the EQ and/or channel routing and it sounds awful.

I have verified the sound issue once by doing a REW freq sweep 20-20k with my system, having been unchanged since an optimum setup, and the measurement showing extreme lack of bass, and much worse linearity. Then when I mess around with turning my DAC off and on and closing/opening EQ APO, the graph returns to perfection again (and it sounds good).

I suspect this is happening sporadically. And I think it might be why I've been going somewhat nuts with sometimes not enjoying my system. I had thought I was imagining it.

When I had a Topping D90 a few years ago, I suspect this phenomenon was happening too. I had measured it to be causing these problems and switched to a different DAC which was fine. I had thought the D90 was faulty.

Now I think there's some glitch happening between the DM7 (and previously D90), and software EQ.

I strongly suspect this is happening on CamillaDSP too.

Worth mentioning: some Topping devices I have or have used have been wired out of phase. I'm sure my PA7 Plus is. (Measurements improve incomparably when wired "wrong".)

Or, at the risk of sounding silly, I just had a strange idea that maybe the phasing of one of my devices (say the DM7) is changing each time I turn it on... If that's possible.

One other crazy idea is that dual-booting could be affecting my PC's time sync subtly and that somehow ruins the USB interfacing.

Chime in if you have any ideas what's going on! Thanks

 

[phofman]

IIUC your issue happens on two totally different software chains: Equalizer APO for EQ on W10, CamillaDSP for EQ on Linux. Then the only common part of the two chains is the USB DAC, right?

 

[SHB]

You have to approach this just like you had a bad cable in an analog system.

Take everything out but the most necessary applications.

Add in one at a time and let that play out for each one to see if it goes wrong. This may not be something that takes a few minutes.

It seems like you’re needing to debug your system. The bug may be in the system or the bug can be in the software.

Either way, this is not going to be something that’s simple or easy.

Sorry to say, this is your personal computer audio hell.

 

[concorde1]

Thanks for the responses.

I will do some debugging with note-taking, and I'll report back once I have determined the actions/events that cause or fix this issue. I'll verify with frequency sweeps in REW.