Oh...it sounds like you may have the Emotiva XMC-1 pre/pro (or similar). I have one also. It has a decent internal DAC; however, HDMI is not the highest quality interface on the XMC-1 for listening to digital music. This forum post explains some of the inherent problems with HDMI audio: http://www.avsforum.com/forum/86-ultra-hi-end-ht-gear-20-000/1296730-hdmi-asynchronous-does-clock-j
For critical listening, I highly
recommend that you use either the USB audio or one of the COAX S/PDIF inputs instead. Also, instead of directly connecting your PC to your pre/pro, buy a network audio adapter like the SOtM sMS-200
, Sonore Sonicorbiter SE or microRendu
, or a Raspberry Pi running Roon Bridge
. These devices are small, lower power, fanless, completely silent, and produce no vibrations. Using one of these devices enables you to remove the PC from listening room. This will lower the noise floor and allow you to hear more deeply into your music, potentially revealing the subtle differences between CD and higher resolution formats, etc.
Until you are able to use a connection that's better than HDMI from a directly attached PC, I recommend against investing in high resolution content. Even then, the DAC in the Emotiva is limited to 192kHz, so that content will have to be sample rate converted to 176.4kHz. If you truly want to experience sampling rates above 192kHz, you will also need to invest in an external DAC.
I don't mean to sound critical if your current setup. I just want you to know what changes are required in order to hear what you are hoping to hear so that you can decide for yourself if this is something worth exploring. I know there are several members of the A-VCOA who would be happy to have you come over to hear the differences in these formats on a more resolving system. I encourage you to leverage that resource. You're welcome to come by my place as well...but I live in San Jose, CA, so it's almost certainly more convenient for you to sync up with Lee or someone who's local to the Atlanta area. :)
I hope this helps...