azimuth adjustment when you transfer and convert cassettes to cd

Cassette tapes run at a very slow speed of 17⁄8 inches per second (ips) with a very small track width of 1.59mm

Cassette decks when they left the factory or a service centre should have been aligned to a standard reference for the position of the record and play heads. Unfortunately they often weren’t all the same and over time the alignment can drift, get knocked out or manually ‘fiddled with’ by an owner.

What this means is that unless you’re playing back your tape on the machine it was originally recorded on, you may not be getting the maximum quality as the angle of the head to the recording or azimuth will not be optimal.

Without calibration tones recorded at the start of the tape (which is very unlikely on most domestic cassette tape recordings), you must set the playback azimuth manually. A few high end tape decks, namely those made by Nakamichi, either had a easily accessed Azimuth Adjust or could even automatically adjust this throughout the tape. The Nakamichi Dragon was one such tape deck and could be the best, if working well, for high quality playback.

If you want to transfer or convert a cassette to CD and adjust the azimuth yourself this is the easy way to do it:

  1. Look at the tape path (everything the tape will move across) and if it looks brown and dirty get some isopropyl alcohol and give it a good clean with a cotton bud.
  2. If you haven’t demagnetised your deck for a while now would be a good time to do it..
  3. Power up your cassette deck, which hopefully works correctly and doesn’t have too much speed instability!
  4. Pop your tape in the cassette well and start to play.
  5. Turn your amplifier’s volume up and if you can put it in Mono.
  6. Now, look under the tape machine’s playback or combined record and playback heads you should see a small screw or nut possibly with anti tamper paint on it.
  7. Using an appropriate tool, turn this nut or screw a little left or right while listening to the audio.
  8. You should hear the recording, especially if it has a lot of high frequency content such as cymbals etc. get bright and dull sounding or more technically get more in or out of phase.
  9. Your aim is to get the most in phase or bright sounding playback.
  10. Sounds better now?? Great, start to record using you favourite computer audio software. We like SoX for the control but there’s a huge range out there.