Audio DiffMaker is a freeware tool set intended to help determine the absolute difference between two audio recordings, while neglecting differences due to level difference, time synchronization, or simple linear frequency responses.

The difference recording  that results is only what has changed between the two recordings.  If anything – a change of component, a treatment, mechanical damping, etc. – is having any audible effect on the audio signal in a system, the difference recording will have audible content. The end result is primarily intended to be evaluated by ear.

Presented at the 125th AES convention. “Detecting Changes in Audio Signals by Digital Differencing“

www.libinst.com/Audio DiffMaker