Mark,
I bet you're about to embark on a rediscovery of your collection. After a month with M3s, I've come to appreciate the different ways good recordings can be made. Acoustic instruments should sound natural. Take Miles Davis's Kind of Blue and John Coltrane's A Love Supreme. They're both well recorded but quite differently. The Columbia studio for Miles was a spacious converted church which gives depth to the recording. For Coltrane, the smaller studio of Rudy Van Gelder and closer microphone placement give more immedate, intense results with less resonance. Each style matches the material. What's great about the Axioms is how they let both shine. Kind of Blue is a forgiving record, but it still opens up in detail with better speakers. Steely Dan records are the same way to my ears. Trane's horn on A Love Supreme can sound harsh or weak (or both), but the M3s keep the energy without screeching -- it really brought home to me the frequent reviewer's praise for the extended, smooth treble from Axiom's titanium tweeter.
So I guess the bottom line is a good recording is one where technique complements the music and doesn't call attention to itself.
