The choice of music ....
We're curious as to why you picked organ and guitar as a WAV v. MP3 comparison. As I've reported here before, the organ sounds good on every loudspeaker (it has a narrow frequency range and limited harmonics) and obviously the (acoustic) guitar has a wider frequency range but almost no dynamic range at all.
Originally Posted by STHLS5
As Mod1 said, what are you actually trying to listen for? You know what the secret of a really good research test is? It's thinking through the likely outcomes, and constructing the test to maximise the comparative differences long before lifting a finger to actually perform the test. In this example, musical selection is of paramount importance.
Alan A. Shaw
Harbeth Audio UK