How to set optimum Spotify audio format?

[Nutul]

Hi all,

I'm always looking to improve sound quality and trying to do that for the Spotify renderer as well. But I struggle a bit with how to select best settings for my hardware.

I have two RPi's, both connected to an USB DAC (a Peachtree audio decco65 dac/amplifier and a Highres microstreamer).

Not sure if you can see the attached picture, but in Spotify Config I set bitrate to 320 and the audio format to S24 as the DAC is 24bit. However I'm doubting a bit if the latter setting is correct. How to I find out the max output format my DAC supports?

I've tried suggestions like aplay -L and librespot --device ? commands in terminal but they do not give me a supported format. 

Any suggestions how to proceed on this one, many thanks for your support in advance!

I believe that if the supported format of your dac is S24 you might want to use S32

Cheers, Al.