Tape Deterioration on NOS LP Tapes

[Edward Huggins]

About 10 years ago I bought a decent stock of Quantegy LP tapes (7" and 10") from "Studiospares" so as to future-proof myself for new R2R recordings.
I was right as it's almost impossible to find LP tape these days.
Even so, although these tapes are still in their sealed boxes, what degree can I expect there to be of some kind of chemical deterioration?

[Bazz4CQJ]

Did you follow the recent thread on "Signal Levels" like me? It was the first time I heard the term "sticky shedding syndrome" (SSS).

Doing a little Google research, it seems that some makes suffer badly from it and other much less so. Assuming that your packaging is just a plastic film (as distinct from a metalised bag) that will probably not have made much difference, as water vapour diffuses at significant rates through all such films.

Apparently, tapes suffering badly from SSS can benefit from being "baked" to remove moisture, but it seems to be short-lived benefit. Beyond that, I'm still on my learning curve. I have just a couple of tapes dating back from the sixties, which are important to me, but I've not owned a reel to reel for >30 years, so have nothing to check them out on.

B

[paulsherwin]

These tapes are not known to suffer from SS. The problems mainly affect American pro and semipro formulations of the 1970s. There are obviously no guarantees though, and some people have reported quality control problems with Quantegy tapes over the years.

Just unwind a few metres of tape from the spool. If it comes away easily with no adhesion then it's probably going to be OK.

[brenellic2000]

I also bought several new Quantegy reels as reserve stock when they recommenced production, but my 1970s BASF LP35LH reels have yet to fail me!

All tapes can suffer from long term storage, so run them through every so often. Keep them in a cool, dry place, normal humidity and away from radiators (heat increases print though on recorded tapes).

[jamesperrett]

Originally Posted by paulsherwin

These tapes are not known to suffer from SS.

Ampex rebranded themselves as Quantegy in 1995. As far as I know they didn't change the formulations when they rebranded so the problems with Quantegy tapes will be the same as with 1990's Ampex tapes (which started going sticky a while ago). If you need LP tape take a look at LPR35 from Recording The Masters - this a remake of the old BASF formulation.

[paulsherwin]

The sticky shed problem seems to be largely down to a particular Dupont binder which most American manufacturers used at one time or another, mostly for standard play semipro/pro tapes. I would hope that Quantegy knew about this problem and were using a different binder. However, I've certainly heard horror stories about some Quantegy tapes. Googling will find lots of anecdotal stuff.

I agree that LPR35 and its later versions don't seem to suffer from SS. European tapes generally don't, but Ampex in particular became a de facto pro studio standard in the 60s, leading to desperate baking efforts to recover material 10-20 years ago as the SS issue became apparent.

[TIMTAPE]

Yes I'm pretty sure there were problems with some tapes after Quantegy bought out the Ampex manufacturing facility, but it was as much with the long play tapes (457/407) as the standard play (456/406). I believe though the binder issue was eventually sorted out. The problem can be knowing which batches were affected.

I'm not sure "desperate" would be the best description. Careful baking of SSS affected archive tapes has been routine practice for many years, is normally quite safe if done with knowledge and skill, and I suspect will continue to be, although I've read reports that some baking times have had to become extended and/or temperatures higher due probably to the longer time window for the tapes to have absorbed moisture from the air.

[red16v]

Just to divert a little if I may please. On the 'Signal levels' thread I have started my project to convert my 40 year old tapes from my Akjai X201D to my iMac for preservation. Some of the tapes are squeaky as they pass through the tape path, some are clearly shedding oxide (and lots of it in some cases!), some reels seem reluctant to 'unwind' off the supply reel.

Does the team have any suggestions to try and help me get over these problems? Naturally I have heard of baking tapes, is this something I can try as an amateur at home - unfortunately I don't have any spare tapes with which to try any suggested techniques.

PS, I did find that putting some old fashioned plumbers ptfe tape around some of the guides post has reduced the problem in some but certainly not all cases. Looks like some of the tapes are trying really hard to 'stick' to the guide posts and are reluctant to move through the tape path - even in full rewind mode. No doubt these symptoms are familiar to some here who have tried the same thing.

Maybe deserving of a new thread if the moderator would prefer? Any suggestions welcome.

[paulsherwin]

It sounds as if you do have sticky shed problems. You can bake the tapes yourself, but that is a lot of palaver for just a few tapes - you can't just stick them in a domestic oven for 30 minutes at regulo 2. People who do this professionally use custom built ovens. There is plenty of info if you google.

You could pay to have the tapes baked and digitized if they are important to you. Several forum members can do this.

[Peter.N.]

I have a quantity of tapes, some of which I recorded in 1959 on a Philips 3542 (pick of the pops David Jacobs) I tried them on an old Elizabethan I had here and they sounded terrible so I thought about throwing them out, I'm pleased I didn't though because a friend on mine brought up a quality tape recorder and they sounded brilliant on that.

Peter

[paulsherwin]

Tapes made before the late 60s don't usually suffer from SS, though they can deteriorate for other reasons.

[jamesperrett]

Originally Posted by paulsherwin

The sticky shed problem seems to be largely down to a particular Dupont binder which most American manufacturers used at one time or another, mostly for standard play semipro/pro tapes. I would hope that Quantegy knew about this problem and were using a different binder.

Ampex claimed to have fixed the problem by the late 1980's but the tapes I have from that era have gone sticky. I was surprised when I first started to encounter it on these newer tapes from our studio but I don't think Ampex ever really got to the bottom of the problem, despite their claims and protestations. They symptoms would have been well known at the time of the Quantegy rebranding but not the solution it appears. Unlike most manufacturers at the time (3M, BASF, Agfa, etc), Ampex/Quantegy were not a chemical company so I wonder if they lacked the in-house expertise to fix the issue.