+1 audioengr statement regarding the USB converter. I own a Berkeley Alpha USB Converter and it made a big difference for my system. Oh, and don't forget to trust your ears more than all of us who have never been in your room and don't get to hear in real time what you are hearing. This community is helpful and opinionated and diverse in beliefs about what works and what doesn't. You have to live with what you buy; we don't. You know what you like better than anyone else and chances are you will know it when you hear it. Welcome to the journey.
Regards
Al
Regards
Al