Old tapes worth keeping.

April 9, 2008 8:19 AM

How should I store these 20-year old cassette tapes with historic value?

At some point, I plan to transfer the information on the tapes to a digital format and googling tells me it won't be insanely difficult. I've also read this question/answer but I think I am not comfortable sending out the tapes due to some sensitive content. In the meantime, I want to keep the tapes in the best condition possible so that when I have the time/resources to do the transfer they will be in good shape. The microphone used seems to be quite high-quality, as there is a lot of audio detail that obviously I would like to preserve. In a standard home environment, what is the best storage solution for these tapes?

posted by typewriter to technology (9 comments total)

Keep them in cases and store them in a cool, dry place away from magnetic fields.
posted by kindall at 8:37 AM on April 9

You want to keep them in your fridge, or possibly your freezer, in sealed containers away from any dirt (or food). Fluctuations in temperature are extremely damaging to audio tape (or any type of magnetic tape, for that matter). A stable temperature is the most important thing to keep in mind here.

The Library of Congress recommends keeping them at "a constant 65 to 70° F and 45 to 50% Relative Humidity (RH). Widely fluctuating temperature or RH severely shortens the life span of all recordings. Environmental conditions shall not fluctuate more that ±10 F or ±10% RH over a 24-hour period. Keep recordings away from light, especially sunlight and unshielded fluorescent lights." That's for medium-term storage (up to ten years). For the long term, "Storage areas should be kept at a constant 45 to 50° F or colder (do not store magnetic tapes below 46° F as it may cause lubrication separation from the tape binder) and 20 to 30% RH for magnetic tapes (open reel and cassette)."

You should also store them upright, and not flat. This prevents the tape from "sagging" over time and damaging itself due to gravity. Keep them in waterproof cassette containers, and for added measure (since they'll probably be in a fridge) in some kind of waterproof box.

Here's an extensive list of resources on the preservation of audio materials. One more thing to consider: you've got to have the tapes in good condition to play them back to digitize them, so keep that in mind. Once they're digitized, you've got another conundrum on your hands: preserving the digital materials.
posted by k8lin at 8:49 AM on April 9 [2 favorites]

Wow, k8lin, that is more complete an answer that I could've hoped for! Thanks. Presumably, the tapes should be completely rewound? I'm nervous that rewinding them will put unnecessary stress on them.
posted by typewriter at 9:01 AM on April 9

Thanks!
Wikipedia's page on Preservation of magnetic audio tape says to play them through entirely before storing, which I meant to include in my original post. You're right: playing causes less stress than rewinding, which pulls the tape more. Rewind only when you're ready to transfer the tape onto another medium.
Also, my first Library of Congress link was broken, so I'm linking it again here. It's a really great resource.
I'd recommend, if you have the budget, buying a mini-fridge, especially if you have more than two or three tapes to store. Another option might be to donate them to a local archives, museum, or historical society, with the stipulation that they give you a copy and that the tapes are "closed" until the sensitive material is no longer sensitive.
posted by k8lin at 9:32 AM on April 9

If you can, fill whatever they're sealed in with some nitrogen or argone. It will help preserve them longer. You can order small tanks of these online relatively cheaply, since they're used in those open-bottle wine preservation machines.
posted by spiderskull at 10:50 AM on April 9

"You want to keep them in your fridge, or possibly your freezer"

Doesn't this run counter to the LOC recommendation "do not store magnetic tapes below 46° F"?

The average fridge is at 35-38 degrees.
posted by Paid In Full at 10:55 AM on April 9

Depending how many tapes, and what it's worth to you, you could go to wal-mart, et-al and pick-up one of those cheap mini fridges intended for pop cans and stuff. Presuming it has a temperature control, you should be able to set it higher than your main fridge, and you won't have as much issues with condensation, or the defrost cycle in your typical freezer.
posted by hungrysquirrels at 3:32 PM on April 9

Well, at the moment I can't afford a fridge for the tapes but I think a nice cool basement closet is in order. The temperature is constant and not damp. But storing them is actually quite complicated so I might focus on getting them digitized as soon as possible. Thanks all!
posted by typewriter at 6:52 PM on April 9

Update: A respected University library will archive the materials as well as properly handle the more sensitive items. Since they are no longer with me, for the curious, the tapes were from a certain student protest which ended with a universally condemned human-rights violation by big-name country almost 20 years ago.
posted by typewriter at 10:22 PM on August 17