Hi Martin
I was asking the selfsame question a while back and would like to give my 0.02 c worth! When I auditioned the Audio Aero Prima Mk II (and compared it with a cheap universal player through a good DAC which included the VDA*2), I found that the gap narrowed so much that I actually preferred the latter combo to the standalone CDP. When I swopped the cheap Hitachi TOSLINK cable with a glass one, the improvements were even more evident. Granted there may be differences in the digital out from various CDPs or universal players, I think the differences are narrower than the benefits one would gain by feeding the digital out into a good DAC. This allows you the choice of a plethora of DACs which could be tube based, Non-OS, battery powered, etc.
I have not heard the VDA*1 but my impressions of the VDA*2 with VAC*2 were very favourable indeed. I will leave others who have actual listening experiences between the two CIAudio DACs to chime in but knowing Dusty's style and reputation, I think you will hear a bigger improvement upgrading your DAC to the VDA*2 than you would by retaining the VDA*1 but changing your CDP. He has a 30-day trial and nothing beats comparing the two VDAs side-by-side. If you have the opportunity, try and get hold of one of the CDPs you mentioned and hear it through the VDAs. Good luck!
Best regards
Dennis
