Hi @Glockers 

Thanks for your post!

It depends on how the Port connects to your HiFi. If you are using the digital output, then Port will not use it’s DAC and your HiFi’s DAC will need to support 24 bit sound too.

If you are using analogue outputs (RCA) then the Port will perform the conversion, at 24 bit.

That’s not what “pass-through” means. Sonos passes through the volume/EQ commands to a compatible downstream amp/receiver. Other than that it’s the same as “fixed”.

Yes  I am using the digital output. So the Port will maintain the 24bit and not downscale it with its DAC. Interesting as I always understood that it was the Sonos DAC hardware that couldn’t handle 24bit.
 

and “pass through” is Sonos terminology and as they explain it the digital feed is passed through the Port bypassing the Port DAC. Nothing to do with volume commands as I understand it.

With the digital output the signal doesn’t touch the DAC, by definition.

In any case the Sonos players have always had at least 24-bit DACs (32-bit in the case of Port). Even in the early/mid-00s any decent DAC chip was 24-bit. The digital volume adjustment requires 24 bits.

What changed relatively recently was the ability to decode 24-bit input content.

Not so. https://support.sonos.com/s/article/3652

Pass-Through

When Port’s line-out level is set to Pass-Through, Port stays at a fixed volume and sends volume commands to amplifiers that support pass-through. You can control volume using the Sonos app, a universal remote, or your voice if you have a voice assistant enabled.