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I suspect you may be onto something there…

Just because I really like the video…

XIPH Digital Audio Video Transcript:

When we digitize a signal, first we sample it. The sampling step is perfect; it loses nothing. But then we quantize it, and quantization adds noise. The number of bits determines how much noise and so the level of the noise floor.

What does this dithered quantization noise sound like? Those of you who have used analog recording equipment might think to yourselves, “My goodness! That sounds like tape hiss!” Well, it doesn’t just sound like tape hiss, it acts like it too, and if we use a gaussian dither then it’s mathematically equivalent in every way. It is tape hiss.

Intuitively, that means that we can measure tape hiss and thus the noise floor of magnetic audio tape in bits instead of decibels, in order to put things in a digital perspective. Compact cassettes, for those of you who are old enough to remember them, could reach as deep as 9 bits in perfect conditions. 5 to 6 bits was more typical, especially if it was a recording made on a tape deck. That’s right; your old mix tapes were only about 6 bits deep if you were lucky!

The very best professional open reel tape used in studios could barely hit 13 bits with advanced noise reduction. That’s why seeing ‘D D D’ on a Compact Disc used to be such a big, high-end deal.

Note that one thing this means is that 5-6 bits is actually not too bad 😉