Last updated 2011-03-05

This page supersedes the blog page for a listing of tapes that have degraded in some way or another. This page is a list of tapes that we will attempt to keep current. For detailed information see the author’s 2008 ARSC Journal article on tape degradation (click here).

Remember that all of these degradation modes are triggered by a combination of one or more of the following:
–original formulation
–batch variations including incomplete reactions during manufacture
–storage history over the tape’s life (temperature, humidity, pollution)

Classic Sticky Shed (Sticky Shed Syndrome or SSS) (generally responds to incubation/baking)

Caution: Playing a tape with advanced SSS can rip the mag coat off the base film and leave it attached to the backing. If in doubt, it is MUCH safer to bake a potential SSS tape than play it. This especially true as the SSS effects are often worse at the centre where the pressures are higher.

The Ampex Tape Baking patent is available here.

Agfa PEM 468, PEM 469 (a half-year’s worth of batches pre-1990) Note, there are mixed reviews on these tapes and most of the bad tape was recalled and transferred at Agfa’s expense. See below,   however, for other Agfa issues. Unike Ampex/Quantegy, we do NOT recommend baking Agfa tapes as a matter of course.

Ampex/Quantegy 406, 407, 456, 457 (1970s-1980s)
Note: Reports indicate that these problems may exist in tapes made in the 1990s
and later, even under the Quantegy name.

EMTEC SM911 As of 2009-01, there are two confirmed reports that 2003-vintage Emtec SM911 is showing the first stages of SSS. A short bake seems to help it. We don’t yet know for how long before it reverts. I hope RMGI has fixed this! Later reports indicate that this may be shed only, without the stickiness AND that it was limited to one or two batches which were mostly replaced. As of this writing, it has been confirmed that batch number B0134007 was involved. This tape may be better placed with the Agfa, below, under non-sticky shed. Please do not assume that either the prior BASF tape nor the later RMGI tape of the same part number suffers similar issues. We do not know how extensive the EMTEC issues are. As of now it seems to be very limited.

Audiotape/Capitol Q15 (early 1980s) Note: This tape may or may not respond to baking.

Scotch/3M 226, 227, 806, 807, 808, 809, “Classic”, and “Master” are the primary SSS tapes

Scotch/3M 250 has also exhibited some tendency towards SSS

Scotch/3M 908, 966/986, 967, and 996 has as of 2009-01 been reported with some instances of SSS. Many other reports do not show this. Looking at the list of 3M tapes on the AES website (click here), and especially the binder types, can provide some help in understanding the progression of failure from SBS to SSS. Seeing the groups there can help predict the performance of a tape not listed above (or below under SBS)

Sony ULH-72-370-BL (stock number X-2441-247-0) was reported by John Schroth at Media Transfer Service in Rochester, NY. This tape responded to baking.

Lighter edge-shedding (generally responds to wiping)

This section was added 2011-03-05 but represents several years of experience with this variant on the SSS degradation. This type of degradation presents some evidence of classic SSS,  but the main difference is that it is not as far advanced and it seems to be much worse at the edges of the tape than in the middle. This may be an interaction between the binder/mag coat and the air.

Tapes with this degradation modality can be played well after a wipe with Pellon. This procedure can be integrated into the rewind process for tapes which are tails-out. A strip of non-woven,  non-fusible interfacing fabric like Pellon-brand can be cut into approximately inch-wide strips on an office paper cutter (using several folds of material. That is then wrapped around a dowel or pencil and then held so the mag coat runs over the smooth surface. The “tail” follows the tape direction and the fabric is slowly unwound. Generally two or three inches (5–8 cm) is adequate for a 20-minute album side at 15 in/s.

One wipe substantially reduces the risk of some of the edge degradation products lodging on the head and increasing spacing loss (which affects higher frequencies more).

Scotch/3M 201 shows this behaviour. This is the first “low noise” tape from 3M and was available in 1.5 mil acetate (201), 1.5 mil polyester (202), and 1.0 mil polyester (203). So far, I have seen this problem only with the acetate-based version (201), but it is worth checking the polyester versions (202 or 203) for this degradation modality. Obviously, the acetate version could not be baked and this was the impetus for searching for a reliable method of addressing 201.

Scotch/3M 206/207 shows this behaviour on a limited basis, based on poorly stored samples. This tape is starting to get a bit stiffer than when new and reports are coming in that wiping it will remove the edge shedding and allow a good transfer. This shedding, of course, can get lodged between the tape and head and increase high-frequency spacing loss.

EMI Tape (with black mag coat and a dull red back coat) from circa 1973-1974

The difference between this modality and the back coating turning to powder and causing spacing loss is that the residue from this degradation, while much less in quantity and density of a classic SSS tape is still slightly sticky and not a loose powder. In other words, it needs to be cleaned off, not blown or vacuumed off.

Soft Binder Syndrome (SBS) (generally responds to cold playing)

In advanced states, this condition results in a squeal, but does not have the huge amounts of gooey shedding of classic SSS or even the lighter edge-shedding. Cold playback works in many cases, but playing with a lubricating film of decamethylcyclopentasiloxane (also known as cyclomethicone and )D5 also works well. Marie O’Connell’s wet playback system also works well.

Melody 169 (a seconds brand of Scotch)

Scotch/3M 175

Sony PR-150

TDK 150H (Thanks  John Schroth at Media Transfer Service in Rochester, NY–he used the O’Connell Wet Playback method on these, so it is uncertain if cold playback would work.)

Some unknown bulk-loaded cassettes do respond to cold playback. A few do not but may be coaxed into playback via lubrication with D5 (see our ARSC Journal paper for more details).

Note that the concept of “Loss of Lubricant” is still widely discussed but, as of yet, in polyester-based tapes with polyester-polyurethane binder systems, we have yet to see any documentation that the lubricant is actually disappearing. We had some Sony PR-150 tested and it showed what appeared to be a normal lubricant load.

Pyral (type numbers unknown for this French tape-does not respond to baking may respond to cold playing)

Back-coat turning to powder and causing spacing loss (seems to respond to wiping)

Agfa PEM-526 exhibited this odd behaviour. See our article here. A similar condition was reported with

Agfa PEM-469, see this article. Do NOT bake these tapes. It won’t help and may hurt.

Vinegar Syndrome (Acetate Tapes)

This category is different from all of the above. The above refer to variants on polyester (PET/Mylar(tm)) basefilm tapes with polyester-polyurethane binder systems. These tapes are acetate-based tapes and here the rule is DO NOT BAKE! Most of these tapes are from the 1950s and 1960s, though some were made in the late 1940s, and acetate tape was made into the early 1970s. Any acetate tape can suffer from vinegar syndrome, and it is discussed in more detail in my ARSC paper with references to research conducted on acetate film. The listing here are for the worst players that I have come across or heard about.

This search of my blog will provide a listing of related articles.

Kodak Acetate- & Durol (Triacetate)-based tapes are the primary acetate tapes that we continue to see suffering from vinegar syndrome.