Jim, I had both the Prime IIa and Basic IIIa as my main Dacs running off a Data Basic II transport. The sonic difference is most noticeable where runs of notes are played closely together. For example, on the song Glad from Traffic's John Barleycorn, over the IIIa the recurring piano riff takes on added dimension. The riff sounds more cascading than before, the individual notes more identifiable, its musical identity more evident. The IIIa also lets you hear more deeply into densely layered mixes. For example, on the Beatles Abbey Road version of Here Comes the Sun, it's easier to latch on to the electronic keyboard part. It's not that it sounds louder in the mix but the increased clarity allows you to follow this sometimes buried melody all the way through. When I first heard it through the IIIa it was exciting, like a new discovery.
One could say the Basic IIIa dissembles the performance more, making each part more distinguishable from another. By comparison, because it doesn't call attention to these fine details, the Prime IIa sounds more relaxed. Which one is more "correct" is anybody's guess. Bottom line and maybe most importantly, the move to the Basic IIIa ended my search for something better than the IIa. If you go that way, let's hear how the IIIa mates using the Sony as a transport.
