(06-24-2020, 10:47 AM)jezsinglespeed Wrote: Yep, don't know if I'm out of depth here. My HiFiBerry DAC+ (RPi 4, Moode 6.5.2) is set to reduced volume as per instructions on HiFiBerry Website. Effectively it shows the Digital line in alsa mixer as 86% (-4dB gain) with is as close to the 90% HifiBerry recommend without introducing distortion (assuming its digital clipping in chip implementation) when I set Max ALSA volume to 96 in moode and Volume Control disabled. Anything higher than this - distortion, anything lower - distortion free and awesome sound quality and usability. Hope this helps.
I don't have any distortion even on max ALSA value (digital) and MPD volume set to Disabled (0dB), it happens only when EQ is enabled. This is related to software side, not the DAC itself. And as I said before, the only possible solution is to enable Software volume control and lower it to about 80. The ALSA slider is the hardware volume inside the DAC itself, and it has nothing to do with how the datastream is being fed to DAC input by MPD and DAC driver. Apparently, EQ filter, which resides on software side, is modifying the datastream in such a manner, that it introduces distortion (it sounds like a flow of sand at some fragments of a random track, can't explain better).
