Cassette tapes were first produced at a mass scale in the early 1960s and became popular in the 1980s. Long before DVDs and cloud storage became popular, audio tapes and reels were used to record information. Magnetic tapes have a lifespan between 10 – 30 years and has been used to record and store sound, numeric and textual information, motion, and still images. While magnetic media adds on to the kind of artifacts, we can use to capture and store, their transience and degradability have been a concern for archivists and librarians.
To understand the reason for the degradation of audio tapes/reels, we need to delve into the components that form these tapes. Tapes have three parts – a magnetic layer, binder, and backing – all of which are potential sources of failure.
All these components are susceptible to damage in the following ways:
Instabilities in the magnetic particle (top layer): If there is any change in the magnetic properties of the pigment that stores the recorded information, the recorded signals are irretrievable. The magnetic particle can become unstable due to demagnetization by an external factor like a hand-held metal detector, or suffer normal wear and tear.
Loss of lubricant in the binder: Lubricants reduce the friction of the magnetic top coat of the tape, reducing tape wear. With time, the level of lubricant decreases due to normal wear and tear, frequent consumption, degradation, and evaporation.
Substrate deformation (backing film): Polyester that is used as a substrate backing is chemically stable. However, excessive tape pack stresses, aging, and poor wind quality can cause deformation of the polyester in the substrate, thereby distorting the tapes.
Various factors result in the damage of audio tapes and reels. We have listed five of them below:
While storage options are aplenty now, audio tapes and reels are still of sentimental and historical value to librarians, archivists, and old people. While audio reels will degrade with time, some ways in which the decay can be contained are:
Having said all of that, it is best to create a back-up and copy of the information in modern formats to ensure there is no information lost.