dictation cassette

Microcassette, Minicassette and Grundig Steno-Cassette or Stenorette 543 tape
2 small plastic cassette tapes

Minicassette and Microcassette 30 minute tapes

introduction to dictation cassette audio tape transfer

At Greatbear, we carefully restore and digitise all three types of small analogue cassette tape: the microcassette, Philips minicassette and Grundig Steno-Cassette.

Recognising that these formats and their players and recorders did not achieve very high quality, we offer two options and methods of transferring microcassettes, minicassettes and steno-cassettes

  1. transfer using an original microcassette, minicassette or steno-cassette machine
  2. transfer by respooling the tape into a larger compact cassette shell

Method one is quicker and cheaper, giving good results. Method two will give the best possible quality, as a high-performing machine can now be used with better control over tape handling and azimuth, but will take longer and cost more.

We offer a range of delivery formats for our audio transfers. We use the International Association of Sound & Audiovisual Archives Guidelines on the Production and Preservation of Digital Audio Objects, delivering 24-bit/96kHz Broadcast WAV files, together with mp3 audio file or audio CD listening versions. We're happy to create any other digital audio files, according to your needs.

We can provide the appropriately-sized usb media for your files, or use media supplied by you, or deliver your files online. Files delivered on hard drive can be for any operating system MacOS, Windows or GNU/Linux and filesystems (HFS+, NTFS or EXT3).

Due to varying tape durations and extent of physical tape degradation, it’s not always appropriate to create generic prices for our services. We’ve found that assessing tapes prior to confirming costs is a more accurate and fair method to provide the best value transfers for our clients

We offer free assessments - please contact us to discuss your project.

For an introduction to our assessment and treatment processes, please see our guide to "what happens to your audio tape".

dictation cassette format variation

There are three main types of small analogue recording tape: the Olympus microcassette; Philips minicassette and Grundig steno-cassette. These were commonly used for voice recordings and portable recording. Due to their inherent low recording quality they don’t have a wide frequency response so can only feasibly sound acceptable for voice recordings.

Microcassettes and minicassettes look very similar but are not compatible, with Philips minicassettes being slightly larger and not capstan driven. Grundig steno-cassettes are different again, with an integrated tape counter index.

dictation cassette variations we work from

tape manufacturerdictation tape typetape speed centimetres per second (cm/s)track formatsupported
Olympus / TDKMicrocassette2.4mono - dual sided
Olympus / TDKMicrocassette1.2mono - dual sided
Olympus / TDKStereo Microcassette2.4stereo - one sided
PhilipsMinicassetteapprox. 2.4mono - dual sided
PhilipsMinicassetteapprox. 2.4mono - dual sided
GrundigSteno-Cassetteapprox 2.4mono - one sided
GrundigStenorette 543mono - one sided open reel
1960s design reel-to-reel style desktop machine with telephone handset-style microphone

Grundig Stenorette L tape recorder/player with microphone

image when enlarged shows 2 machines, a portable handheld Philips 393 minicassette machine with strap and a larger desk-top Sony Microcassette machine with digital display

Sony BM-840 Microcassette and Philips 393 Minicassette machines

Minicassette and Microcassette with rulers showing dimensions in caption

Minicassette in 5.5 x 3.5 cm shell & Microcassette in 5 x 3.5 cm shell

dictation cassette tape risks & vulnerabilities

The tape in microcassettes can often snap, pull out from the end of one spool hub or become wrapped around a part of a player’s transport or ‘chewed’. We can repair these problems usually keeping the original shell and minimise any loss of the original recording.

Due to the technical limitations of the microcassette format and its portable design, recording quality may not be very high. These tapes are often good candidates for digital restoration. Using a selection of software tools in particular iZotope RX and Sonnox Restore, our many years' experience and a good acoustic environment, we are able to improve the audibility of speech and reduce a wide range of noise types such as hiss, hums and buzzes that can destroy audibility and reduce listening pleasure.


dictation cassette recording history

The microcassette format was developed by introduced in 1969 by Olympus. The tape width is the same as compact cassette, but its shell is much smaller. By using thinner tape and slower recording speeds, recording time was comparable to compact cassette with the MC90 tape offering 45 minutes per side at 2.4 cm/s or 90 minutes per side at 1.2 cm/s. Due to the small tape size, flexible speeds and portable recorders, the microcassette format was popular as a recording medium for dictation and in answering machines.

The Philips minicassette (1967) has a very slightly bigger format cassette shell. It has been used mostly in professional dictation machines, as its capstan-free design makes the transport simple, robust and suitable for repeated and quick forward and reverse winding. Playback speed is easy to alter for transcribing purposes but speed stability and wow and flutter are poor, making it suitable only for voice recording.