Audio Cassette Speed Calibration Test Tape 3150 HZ

Brand new test tape for calibrating the speed of your cassette decks.

Specs:
- 440 HZ A tone (for quick check with instrument tuner) (or MIDI note 69)
- 3150 hz tone for setting speed with frequency counter and checking wow and flutter
- Recorded in stereo, not full-track

Speed tolerance: 0.16%

Notes
The speed variance to move a half tone from A 440Hz to A# at 466.16 Hz is 5.9%. That's a lot .Most cassette decks should be operating well within half or a third of that range. But if you're doing tape copies you need a much tighter tolerance to avoid cutting off the music or having a huge empty space at the end of the sides, especially on longer tapes of C-50, C-60, and longer 

We have compared the speed of our test tapes against old test tapes from Sony, TEAC, and Nakamichi. Our test tapes play back the 3150 Hz tone with comparable variance as we found with those old test tapes. The variance of our tapes is +- 5 Hz or 0.16%. When adjusting speed your target is 3145 to 3155 Hz. But most of you won't have a frequency counter so we've included a 440HZ A tone to calibrate with any guitar or instrument tuner. You should be able to get within 0.5% using the 440 Hz tone.

If you want to dub your own tapes consider this:

1% speed variance on a 30 minute side is 18 seconds per side
2% speed variance on a 30 minute side is 36 seconds per side
3% speed variance on a 30 minute side is 54 seconds per side