HI Everyone. I'm thinking of buing one of the following amps. Yamaha RXV350,(5.1), Yamaha RXV 450(6.1), or Sony 597(6.1). I have a Sony DVD/SACD DVPNS 700 player, A Sony minidisk deck and i'm currently using an.....hmm...well,an antique amp. by sony. i'm listening mostly to jazz and movie soundtracks and i just love treble.Which one of the following models you think will have better sound quality and better responce to higher frequencies? thanks!!!!