WiiM Pro connecting to Denon AVR-S960H

[Dru2k]

WiiM Pro has TI PCM5121 DAC which can decode 384khz/32bit and outputs 192khz/24bit
The Denon has a 32bit AKM DAC; unspecified model; is advertised as premium AKM 32bit DAC which would mean it likely decodes 768khz/32bit and outputs 192khz/24bit.

I am not a fan of the HEOS app. I am trying to figure out what is the technically best way to listen to high res audio specifically Plex FLAC/amazon HD streaming.

My thinking is the Denon has the better DAC in this instance; so might as well just feed it a digital signal? I currently have it connected via TOSLINK with WiiM Pro audio output set to 24bit 192khz FIXED resolution. It's working great no issues.

Would there be any reason to use COAX or RCA instead? And feel free to correct my thinking on this topic.

 

[harkpabst]

My thinking is the Denon has the better DAC in this instance

If it's unspecified we don't really know. Even if the chip was specified we don't know if the implementation is better done in the S960H or in the WiiM Ultra Pro. So, it's virtually impossible to judge the "technically best" solution.

I currently have it connected via TOSLINK with WiiM Pro audio output set to 24bit 192khz FIXED resolution

Why fixed resolution? A high fixed sampling rate and bit depth is not necessarily better, because every source with lower native resolution has to be upsampled by the WiiM Ultra Pro. Fixed resolution is mostly a workaround for DACs that create popping or crackling noise when switching between resolution settings.

Would there be any reason to use COAX or RCA instead?

Coax is technically identical to optical as far as the signal is concerned. Unlike coax or RCA, the optical connection does not carry an electrical ground (or any electrical connection), which can be beneficial. Some optical inputs don't support 192 kHz sampling frequency (or not reliably).

In the end you have to decide for yourself if you really hear a difference between the different connections. Be warned that even slight differences in level will almost always make you prefer what's playing louder. Even if you hear a difference, make sure to not just go with the first impression, but judge if there really is an improvement ... or just a difference.

 

[Mr Ee]

Rather than frantic switching and volume matching, just try both for a few days each and see which you prefer.
However, for me, pretty much anything is better than the wiim pro analog output. I don't know why @harkpabst keeps referring to the ultra
As for fixed 192khz output from the pro, imo unecessary unless you have a particular reason to set it.

 

[Dru2k]

Thank you for replies; I was setting it at fixed resolution because I am trying to make sure I can play 24 bit 192khz reliably without stutter as harkpabst mention some optical inputs do not support 192 khz reliably. It's a new AVR to me so just making sure it can handle that sampling rate properly. Once I feel its working at that rate without issues I will turn off fixed resolution. I've been in scenarios where 16 bit / 192khz will play without stutter but 24 bit / 192khz will stutter but changing the cable or loosening the plug at receiver end will all of a sudden get rid of the stutter.

This particular AVR I've noticed that same cable same WiiM but different optical inputs will result in different playback ability. Output 1 can get up to 24bit, 94khz but Output 2 can get up to 24 bit / 192khz. I'm assuming there may be some dirt or damage in output 1? Because it should be identical DAC.

I really doubt I or anyone can tell the difference between optical and coax with proper volume leveling; that is why I posed this question. I think I am content with just sticking with optical. I however can tell the difference between 320kbps spotify and FLAC audio so figured I might as well optimize my system as best as I can.

 

[harkpabst]

Output 1 can get up to 24bit, 94khz but Output 2 can get up to 24 bit / 192khz. I'm assuming there may be some dirt or damage in output 1? Because it should be identical DAC.

Even if it's the same DAC there could be different TOSLINK receivers in use. At least in theory. Unless this was explicitly specified by Denon I'd rather think of irregularities and varying quality spread.

I think I am content with just sticking with optical.

Certainly a very reasonable idea.