Tape Recorders

Reel to Reel & Cassette Deck Repair

Most electronic repair services do not include reel to reel and cassette deck repairs – and if they do it is important to make sure that they have the necessary tools to not only service, but also calibrate them.

Here at M² we have the necessary reference tapes to complete alignments on both reel to reel and cassette decks.

Reference Tapes and Alignment

For reel to reel playback alignment we use full-track Magnetic Reference Laboratory (MRL) reference tapes. We stock the three most common speeds of 1/4″ reference tapes: 3.75IPS, 7.5IPS, and 15IPS. We also have 1/2″ at 15IPS, 1″ at 15IPS, and 2″ at 15IPS for the larger formats.

MRL Reference Tape

For cassette deck Playback alignment we stock the full-track A. N. T. Audio reference tapes. These include the 200nWb/m Dolby Tone Tape level setting, and the 70uS Combination Tape which contains HF and 3kHz tones for azimuth alignment and speed adjustment, respectively. For mechanical adjustments we carry a mirror cassette and a torque meter cassette. The mirror cassette has a 45 degree mirror built into the cassette shell for aligning the tape path, while the torque tape is used for measuring and setting the take-up torque.

Alongside the playback reference tapes, we also carry a large assortment of blank tapes for record alignment.

Blank Tapes for Reel to Reels:

  • RTM SM900
  • RTM SM911
  • RTM SM468
  • Capture 914
  • Capture 930
  • BASF LGR30
  • Maxell UD-XL 35-180

Blank Tapes for Cassette Decks:

  • Fuji DR-1
  • Maxell UR
  • Maxell XLII
  • Maxell MX
  • RTM Fox C60
  • Grundig C90 Ferric
  • BASF Ferro Extra I
  • Denon HD8 II
  • Sony HiFi 60
  • TDK SA90
Blank Cassettes

If the tape you wish to have your deck set for is not listed, we recommend bringing a blank reel or cassette with you so that we can set the bias and record levels for optimum performance.

If no tape preference is given, reel to reels will be aligned based on their reference fluxivity. Consumer machines that typically run at a lower flux level will be set for SM911, and semi-pro & professional decks that run at higher flux levels will be set for SM900. These tapes are chosen by default as they are current production tapes.

The default cassettes used during record alignment for Type I 120uS, Type II 70uS, and Type IV 70us, are Maxell UR60, Maxell XLII, and Maxell MX respectively.

Head Lapping

What is head lapping?

As heads wear, a flat spot in the center of the heads forms, causing the tape to not make contact with the apex of the head. This causes a reduction in high frequency response. Relapping is the process of removing material from the tape head until the original shape is achieved. This can only be done with perm-alloy or cobalt heads, and not with glass/ferrite or cassette deck heads.

Maurizio was trained by a Studer technician in head lapping, and has successfully lapped many heads from all kinds of tape decks. The process is done by hand, and very carefully to ensure the correct shape of the head is achieved.

Revox A77 Heads, Top – Before, Bottom – After Lapping.