the answers in detail to your questions could (and do)fill books.....
walters said:
What does the Tape Heads do to the audio signal?
Does the Tape heads compress the audio signal?
Does the Tape heads Magnetize or Demagnetize the audio
signal?
Does the Tape heads Saturate the audio signal?
most tapes use a metal oxide (think rust) coating that will take and hold a magnetic field
the audio signal comes into the recorder and drives what is like a tiny eletromagnet in the head the tape passes over. this is not a digital process and if the signal is overdriven the entire volume and frequency information can not be accepted by the tape but the tape does its best, and clipping (overdriving) in this process is much less noticable (and some even like it) than on digital, where clipping can cause very nasty artifacts.
there are read heads and write heads in a tape recorder. the speed at which the tape passes over the heads also effects the signal to noise ratio, faster (up to a point) is better. tape formulations also play a role as that effects their magnetic coercivity.
very few people will argue that digital recording on a computer is faster and easier.
very few people will argue that a cassette tape is as good or better than an average digital system.
were the debate mainly lies is in high end digital versus high end tape, like using a 2 inch video tape machine for audio. a lot of people, with much experience, are on both sides of the issue.
I feel sure apl could give you a much better explaination then me, but i guess he just decided to blow you off.
oh, yeah, tape oxide or pure metal coating formulations are argued over also.