Professional cassette deck calibration procedure, plus why Nakamichi decks are the best tape decks.

How to professionally calibrate playback and recording on any cassette deck, with the bonus demonstration of why Nakamichi decks are better than anything else. I will die on this hill. I've worked on many of the so-called Nak killer decks and not one has the set of features I outline here on this relatively basic CR3.

Peebles Audio Engineering calibration tapes:
https://www.naks.es/