Christoph's Tape Pages - FAQ “lubricating” Tapes

Question:
I got some old tapes from my father (or bought them at an online auction). However, after a short period of operation with these tapes, my device sounds very muffled and becomes increasingly slower (even when rewinding). A brown or black coating (depending on the type of tape) has also formed on the tape heads and tape guides.

Answer (short):
Dispose of the tape in the trash, remove the reels, and meticulously clean the heads and tape guides with alcohol.

Answer (long):
Unfortunately, over the years it has become apparent that recordings on reel-to-reel tapes are not as stable over time as was thought when the tapes were manufactured. In addition to problems with the copy effect and declining hearing dynamics, at some point the symptoms described above also began to appear. The reason for this seems to lie in the hygroscopic (water-attracting) properties of the magnetic layer applied to the carrier film. The moisture dissolves the magnetic layer from the carrier film and, together with the magnetic layer, forms this lubricating film. Almost all types of bands and manufacturers seem to be affected by this bad habit. Some more (and/or earlier), some less (and/or later). This process can be delayed by storing the product in low humidity and at a constant temperature, but it cannot be prevented. However, there are a few bands where this has never happened, at least not yet. Unfortunately, it is very difficult to pinpoint this to a specific type of band, as it sometimes even seems to depend on the production batch. The only type of tape where this has never happened (at least for me) is the “Revox Type 601.” At the other end of the scale are the famous “Shamrock” bands. Some of these were already greased at the factory. According to statements by the few remaining tape manufacturers, tapes from current production are no longer affected by this problem due to changes in their chemical composition. The coming decades will show what to make of this statement.

Solution:
First of all, the solution described is not cheap (hardware, if not already available), time-consuming, labor-intensive, and probably not stable in the long term. So it's really only worth it for truly important recordings (master tapes, your child's first sounds, etc.). A truly excellent, illustrated guide on this topic was published some time ago by “Herby S.” Since I have no intention of reinventing the wheel, I am making it available for download here, with the kind permission of the author (PDF file, approx. 500 kB).

One more note:
I recently saw an offer on this topic in an online auction. The offer was to coat such tapes with a special agent. As a result, they promised to fully restore the tape. Unfortunately, I can't say what to make of this, as I haven't had any tapes restored there yet. If anyone has already taken advantage of this offer, I would be grateful if you could send me a short report of your experience by email.

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These pages were last modified on: 14.02.2026 at: 18:05:42