[Audiovista]

While getting educated on digital filters, I found an interesting presentation, linked below. Starting on page 26, there is an audiophile friendly description of psychoacoustics basics and fundamentals of audio compression, including MP3. After reading this, I must confess that I have new appreciation for the good ole MP3 and all the thought that went into creating that format.

http://cv.cs.nthu.edu.tw/upload/courses/14/uploads/CS3570_Chapter5_part2.pdf
 

[Speedskater]

MP3 is digital data compression, which is very, very different from analog audio signal compression.

[Audiovista]

MP3 is digital data compression, which is very, very different from analog audio signal compression.

Sure. The "dynamic range compression". Which can also be done in digital domain. Invented for good reasons, today often abused.