so audio tapes work by basically magnetizing certain areas of a tape more strongly than others, right?
couldn’t you use different frequencies on a tape as digits in a base-n (where n is the number of different frequencies) system to store more data than a binary system would?
no, you cannot (and would not want to) do that. the magnetic surfaces can only be set to point in one of two directions. the encoded data does not lie in these cells, it lies between the boundaries of them. all the native disk controller sees “field exists” or “field doesn’t exist” at the cell boundaries. making them be able to see anything more complicated than that would probably cause your soft error rate to skyrocket which would necessitate that you do a whole lot more error-correcting which is expensive in terms of disk usage & i/o throughput. im sure your cell size would also have to be made much, much larger too
another problem you’d run into is that if a read/write head were to pass over a heavily magnetized area encoding a relatively high digit in our base-whatever number system, it’d probably pick up a capacitance such that if the next cell encoded via a weak magnetic field, the capacitance would cause the read/write head to read that cell as one with a slightly stronger field than it actually does
the question of “how do you get these fucker capacitance out of the god damn computer” is worth a nobel prize or two. so don’t ask “what if i just get rid of that”. the only solution would be to have a larger cell size, further cutting any performance you might gain with your change
in the end, you’d end up with a disk that holds like 100MB, has a 22KB/s throughput, and costs seven thousand dollars
fundamentally what you are saying is a possible way of storing data but its complexity would make it functionally worse in all aspects compared to what we have now
audio data is encoded exactly the same way digital data is, just with no attention paid to cell boundaries. the magnetic field switches from left to right just like it does with digital data, but this is meant to bounce the read/write head as to create a waveform matching the pressure waves comprising the recorded audio