It's not really a myth!

We've discussed on this list how ALL acetate-backed media may eventually develop vinegar syndrome, 
and we also discussed how different types of acetate tapes may exhibit different related behaviors 
that all might relate to vinegar syndrome. So that's just about every tape pre-1959 or so.

Then you get into the polyester tapes, which do seem to last longer. However, the sticky-shed 
tapes -- which are a sizable plurality if not the majority of tapes used in the US professional 
commercial sound recording business from about 1970 to about 1997. I've stated here before and I'll 
stick by the assertion that sticky-shed tapes cannot be baked and played over and over without 
degrading the audio quality. My experience is, I start to hear it after 3 or 4 bakes. Also, we have 
the issue of the required baking times increasing substantially over more recent times.

So, the "indestructable" smugness, even if it's warranted, applies only to a relatively small era, 
about 1959-1970.

Having just worked with 1957 acetate tapes and 1959 polyester tapes, I can tell you that the acetate 
tapes were in much worse shape and it was thus quite a bit harder to clean them, play them and 
recover the audio. I have zero confidence that those acetate tapes will be playable "forever." I 
think they get more brittle and the oxide more likely to fall off in the normal course of a tape 
transport all the time. And, if they develop full-on vinegar syndrome, forget it.

If I were a record company doing a realistic assessment of my copyright assets, I would consider 
pre-polyester tapes extremely perishable, early-era polyester/pre-sticky-shed tapes least perishable 
but worth watching closely, and sticky-shed tapes likely limited to a few bakes and playbacks and 
probably will get to where baking won't make them playable, so longer-term perishable. And by the 
way, I'd also consider early digital tape storage formats highly perishiable because of evidence 
that certain U-Matic types and DAT types get sticky, plus the fact that playback hardware is 
becoming rare for some formats.

Regarding Robin's posting, I don't think there's any blanket "wisdom" about old tapes getting 
"dulled out," but I have heard stories about older tapes that were used to cut a lot of LP masters 
get so they don't Dolby-track well and other things related to certain frequencies falling off more 
than others over time. I think it could be that the tapes passed over slightly magnetized transport 
parts or heads here and there, or were exposed to weak magnetic fields for long periods of time, or 
even lost enough oxide for it to be audible just because they were played so many times. After all, 
playback is not a frictionless exercise.

-- Tom Fine

----- Original Message ----- 
From: "Dave Radlauer" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, April 07, 2015 7:44 PM
Subject: Re: [ARSCLIST] More tales of woe from the tape vaults

> There is an urban myth among *civilians* that tapes, or their contents, are
> somehow *evaporating* or going away over time.
> Dave Radlauer
> -- 
> hm# 510-848-8323
> cell# 510-717-5240