SQUEEEEEEEEEEEEEEEEEAK!!!! Is that what you hear when trying to play back an old Ampex or Scotch backcoated open reel tape? When you put the tape on the deck and play it, is it leaving a lot of gooey, gummy residue behind on the heads and guides of the replay machine? If it is, you're facing the problem a lot of engineers and hobbyists alike are facing at the moment. It goes under the name of "sticky-shed syndrome", where over time, the tape's binding materials break down and takes your recorded material with it.

What tapes does this affect? Primarly ANY backcoated tape, but the Ampex series 406, 407, 456 and 457 tapes are affected (their studio mastering/grand master series), and recently the Scotch 226 and 227 tapes have also been known to have this problem. This all started in the 80's, when various tape manufacturers dumped the use of a carcinogen in favour of this new formulation, that they deemed brilliant and that it would last at least 20 years, no problem.

Unfortunately, when it came time for engineers around the world to remaster their back catalogue for CD release, out the problems came. Some tapes were so sticky they wouldn't play, others just gave a high-pitched squealing which then made the machine slow down and eventually stop, and others still left a white powdery substance on the heads. It was later discovered that by baking these tapes that they could be restored long enough in order to get a few extra passes from them - long enough to transfer to another medium.

The recommended practice is to put these tapes in a convection oven for temperatures between 50 and 65 degrees celsius, for a period of up to 8 hours. I can say with confidence though, that any standard household oven also works, having recently restored 200 reels of old programme material from a radio station that no longer exists. Once you have baked a tape, take it out and let it cool overnight. Load it onto the deck, and I guarantee you'll have your precious masters playing and playing well at least for a few weeks, which is ample time to have them transferred onto a better, more stable format.

The best tape decks to use for this purpose are those with rotating guides. The Teac and Tascam series of decks are recommended, as well as the professional Studer A810 series. If you've come this far with your material, make sure to make an everyday working copy, as well as one to keep in a safe place.

It was known much later that Ampex had closed, and picked up again under the new name of Quantegy. This company are still marketing open reel tape in Australia as well as digital formats, however they now use a new formulation and are telling us that the problems of the past should never happen again. We live in hope...

Baking works well for any width of tape you happen to have, from quarter-inch right through to 2-inch. Having done it myself, I can say the method works, and it works well. If you're not game enough to do the baking yourself, Quantegy will do it for you for a set price. But take my word for it. Once you've got the material off the tape onto somewhere else, then who cares what happens to it? You can't re-use it for future recording and playback as it will revert to its' sticky state within a few weeks, and if anything, can make great doorstops!

Related link:

http://www.tangible-technology.com/tape/baking1.html