Compact Cassettes / standard music cassettes and why they should be avoided as main media

The classical compact cassette tape developed by Philips was common for audio storage around the 1970:s to the 1990:s, and still as of writing this there are a lot of them left.

If you have no experience with this type of storage media you may get fooled that it is a quite nice format. But beware, it is not.

- According to many sources online the tapes can only do about 6 bit in quality, compared to compact discs (CD:s) which do 16 bit. So anything you record on a tape is degraded to 6 bit.

- This is an analog media, so it must be recorded and played in realtime if you don't want to experience yet more loss in quality. There are several high speed double decks out there that allow fast tape-to-tape copy which also can be tricked to high-speed copy recorded content to a computer by recording the pitched audio and then speeding it down. But if you do, you will not get the same quality as if you play it in realtime. 

So, if you have content on this type of tape that you would like to get stored on your computer, then you will have to wait at least the time it takes to play it, you cannot just copy it over in high speed like it was a disk or even a DDS tape. Multiply your number of tapes with the playback time, for some of us it results in days required to get it off the tapes.

- It is a sensitive media. Dirty, worn or just bad quality tape decks like to eat tape and wind it up, preferably around some of the the moving pins and gears in the machinery. Suddenly when you try to playback a tape you find that your precious recording is crunched. The only way to fix it is to carefully wind it back in to the tape, clean the machine and carefully try to make the tape flat and playable again. Sometimes you will have to cut out parts that simply are not usable at all due to the mistreatment.

- It is a VERY sensitive media. Winding up, cutting out unplayable parts and taping them together again is not fun at all. Maybe the first time you feel very vintage, but not the 10:th time. Sometimes you will have to open the covers of the cassette to get things right. When you are there you must be very careful. If you try and fail to lift one of the rolls holding the tape you will end up in a real tape sallat, totally ruining your recording.

- The speed vary between tape decks. That's right - different playback devices have different playback speeds. Some even vary while playing. Just because it is a double deck does not mean both decks have the same speed. So 1 min can be 50 seconds on one machine and 1 min and 10 seconds on another. Inside many decks you may calibrate the speed, but with what? You'll need a reference tape, which may be found on eBay, or use a musical cassette with prerecorded music and just hope that the time of the tracks is accurate.

- Some tapes are recorded with Dolby B or Dolby C noise filtering, some are not. As if it wasn't enough problems some tapes need to be played with the Dolby filters activated to be correctly played. If there are no notes on the tape, then you'll have to play and store the tape two times or even three to compensate for no-dolby, Dolby B and Dolby C.

- Some tapes makes the machine dirty as the glue and other stuff comes off. Suddenly your tape deck and cassettes sound exceptionally bad. The reason may be that one or more of the tapes you played has smeared down the heads and the pins in the machine. The fix is easy for the deck, you'll need Isopropylphenol and some tops. For the cassettes it is worse - some have suggested baking the tape for 1 to 8 hours in an oven for 50 degrees, but that bends the cassette covers.

- Tape decks break. Rubber bands inside dry and are sometimes very hard to replace.

- Analog cables have different impedance and decks have an internal balance control, making the balance unsure. If you measure the audio cables with a multimeter you'll find that different cables have different impedance between the channels. The left channel may have much higher impedance than the right, making the sound slightly unbalanced. Then add that many tape decks have a balance calibration like the speed inside (do not touch it if you are not really sure that it is out of balance).

Using cassettes of this type for plain retro enjoyment and fooling around is one thing. But having them as the primary storage media is strictly discouraged. It is very time consuming and sometimes very hard to recover data from these types of tapes. Do not put yourself in that situation.

This is a personal note. Last updated: 2016-03-02 20:57:31.


Don't forget to pay my friend a visit too. Joakim