Yeah I owned the Amazon(5 pairs infact). It's a little dark compared to say, similar Acoustic Zen silver ref(which I like better for sure). The Acoustic Zen Matrix ref(silver/copper) is your next try! it's as good as any copper/silver made I believe. It works superbly between amp and preamp for certain. It's got incredible bass, very high resolution, extension, and clarity. I think it's worth a shot.
have fun
have fun