Depending on the width of tape, the equalization of your machine, the amount of test tones, and the length of each tone, the tape speed(s), and which fluxitivity level you want, there are different calibration tapes for different needs. They are one of very few companies, (if not the only company) that still makes them fresh.
They're pricy, but worth it. You can send them a money order and have them ship it to you.
