is it true that sony erricson "K" series and "W" series differ in sound quality??? it looks so weird to me when i checked its specifications in the gsmarena.com site. because, k series for eg: k790 has a polyphonic feature of 72 channels, while the w series for eg: w850i has polyphonic feature of 40 channels only... my question is, which one sounds better? and i also heard that w stands for walkman series.... so the walk man series should sound good right??? if that is the case, why sony people are keeping low quality products in the walkman range??? what does this 72 channel, 64 channel or 40 channel in polyphonic feature means??? pls anyone explain in detail so that i can choose which series is better in sound output... and why??? thanks in advance.