Acoustic tape, also known as adhesive tape or sticky strong deck tape is an old-fashioned recording medium. Acoustic tapes are made of a layer of magnetizable material on top of a backing material such as plastic film with an adhesive layer on one side. Sound signals are recorded by pressing the tape up against a rotating drum coated in magnetic oxide with a gap in the magnetic field. Each time a sound or other signal is sent across to the other side, a copy of it is recorded into that section of the tape as a pattern of magnetization changes. The change can be considered analogous to a waveform, and so this method is refereed to as “magnetic recording”. This is the original form of magnetic recording, and has been universally superseded by other, more stable magnetic media such as flexible tape and disks.
Acoustic tape was very popular in the 1980s and early 1990s for making demo tapes (demonstration recordings that could be sent to record companies). Demo tapes were typically created on an audio cassette, using a variety of formats, including ADAT or MiniDisc. The idea was to use low-quality tape stock so the demo could fit more songs on it, which would quicken up the process of making demos for record companies.
It is still possible to buy this kind of recording medium today, but it has largely been superseded by other digital media.
The backing material is typically a thin, flexible plastic film that easily crinkles and tears, though in some cases the backing can be paper. Acoustic deck tape joist is very light weight and quite pliable, which makes it easy to handle when sticking down to a drum or other surface for recording purposes. Acoustic tape is sensitive to heat and humidity, so tapes should not be left in a hot car for too long or else the tape will warp from the heat.
The magnetic alloy film has a tendency to come off of the backing material under certain conditions. This can be tricky when preparing the recording medium, as it is difficult to know how much of the magnetic layer is going to adhere to the backing material. This leads to a loss of fidelity in recordings, as sound information can get lost when joining two pieces of tape together. If there is too much magnetization on the magnetic backing it can be difficult or impossible for playback devices to “see” the signal, which will cause any recording to sound very weak and washed out.
The adhesive layer is a water-soluble glue that can get into the playback device’s heads, causing the magnetic particles to come off of the backing. This will cause a loss in fidelity and eventually render the medium useless.
Acoustic deck joist tape is fairly delicate and should be handled carefully so as to avoid tearing it, and has a tendency to fade when in light for an extended period.
Properties:
- magnetic medium
- flexible backing material “plastic film”
- adhesive layer holds layers together
- the strength of the magnetic oxide decreases over time due to heat and humidity
- can be difficult to record