Thanks for the comparison. Very well written. I am just surprised you didn't include the other N9xx device, N91. That should have made a perfect comparison.
Audio Quality The Nokia N91 has been praised with an impeccable reputation of the best sounding mobile phone ever produced (the majority of stand alone portable music players can hardly compete with it either).[5] N91 uses a special DSP-33 chip set made by Toshiba and a powerful in-built Harman Kardon amplifier to boost up its volume while using acoustic, resulting in louder, deep bass and rich sound with perfect low and mid range frequency which has not been achieved by any iPod or Sony Walkmans.[6] Test conducted, the N91 wins over iPod Nano in its signal to noise ratio, output power at full volume, and output at 10–100 Hz.[7]