i might just get me a pro to try it out

This or Xonar Essence STX II?

This looks promising

Very much looking forward to trying some of these audio cards.

These cards really worth it over even really good on board audio? I have a ASUS ROG Crosshair VIII Hero X570 
 
I have separates - Rotel Pre-amp RC-1572 and a Rotel 200W x2 channel Amp - It's a 2.1 set up - SVS sub rounds it out.
 
Right now I use Optical out from the PC, the Rotel does have USB connection to the PC but it creates problems if I want to switch to CD -and then later switch back.  The device drops entirely.  So it seems USB is out.
 
 

bkleinke
These cards really worth it over even really good on board audio? I have a ASUS ROG Crosshair VIII Hero X570 
 
I have separates - Rotel Pre-amp RC-1572 and a Rotel 200W x2 channel Amp - It's a 2.1 set up - SVS sub rounds it out.
 
Right now I use Optical out from the PC, the Rotel does have USB connection to the PC but it creates problems if I want to switch to CD -and then later switch back.  The device drops entirely.  So it seems USB is out.
 
 

It's definitely one of the best audio options available and I would say I can notice a difference but how much that matters is going to be up to the listener. With you having audio equipment it seems like you would be a good fit. On the other hand someone who has gone to a lot of loud rock concerts and uses $29 speakers from Walmart might not notice an improvement. 

OBE, and btw they will be out of stock for a while since AKM fire destroyed the source of the DAC.

Hoggle
 
It's definitely one of the best audio options available and I would say I can notice a difference but how much that matters is going to be up to the listener. With you having audio equipment it seems like you would be a good fit. On the other hand someone who has gone to a lot of loud rock concerts and uses $29 speakers from Walmart might not notice an improvement. 

 
What connections were you using before and after the upgrade?  I.E. are you using the DAC in the sound card by using outputs direct to a speaker - or a TOSLink or coax connection to a receiver or preamp (in which case the DAC in the sound card is not used)?