I've been in this situation a few times where I would like to directly comare two audio files sonically to each other.
Maybe to decide on a different mix or to compare "full dynamic range" versions with the original CD tracks.
Is there a program that can play back two comparable audio files at the same time and switch the output from one to the other at the click of a button or a key, so that the sound continues at the same point on the other file without pausing or having to open another player instance?
abx, available in the Ubuntu software repositories, is designed to perform audio ABX testing. It allows you to determine if you can discern audible differences between two samples.