Question about word length


I started my trial period a few days ago. I’m really impressed by roon so far. The user experience is pretty much above everything I have tested so far (for the last 15 years).

I’m not using computer audio on a daily basis (I’m usually sticking to record and CD playback) so please forgive me if the answer if obvious.

My DAC is supposed to accept resolutions up to 16/48. At least this is what the Advanced tab is telling me in the USB DAC properties in Windows 10 64.

So here is my question. I downloaded a 24/48 album from HDtracks. I can play it using roon no matter if I select 16 or 24 bits in the driver settings of the connected USB DAC (JPLAY Asio driver). If I select 16, roon down-samples it (visible in the Audio path). If I select 24 no conversion is displayed in the Audio path (but the file still plays!).

If I try to play the same file using JPLAY I get an error. JPLAY cannot play the file because it is 24 bit.

I’m not really sure how this is possible and I was wondering if somebody can help me shed some light on this.

Many thanks in advance.

What DAC is this?

Its a custom made DAC using 2x PCM58 as far as I remember.