Hi,
Is there any software with which I can check how much hearable data is lost roughly?
I am working on a diploma thesis, and I want to know if there is any other way (besides listening to the encoded files) to check the quality loss.

Greets,
trashorr

There are methods for getting "Objective" difference grade or similar, that gives approximate quality of the degraded signal. There have been many discussions about this. Recent one is
http://www.hydrogenaudio.org/forums/index....=30&t=59835
You might also search for EAQUAL or for PQevalAudio.