I would definitely re-house the cassettes as others have suggested, I have
had very good success with this.
I have also baked 'open' cassettes and have even, in severe cases,
eye-dropped a little isopropyl alcohol over the tape, let it evaporate
before baking with one side of the shell removed.
First port of call has been the rehousing.
On Thu, Feb 21, 2013 at 7:20 AM, Karl Fitzke <[log in to unmask]>wrote:
> Greetings, and thanks right away for your interest and potential help with
> the following:
> We have a set of approximately 30 SKC Brand, GX and LX model, Type I
> cassette tapes on hand to transfer. They are 60 minute tapes.
> The original field recordist is from New Zealand, where these tapes were
> A number of the tapes start squealing after five to twenty minutes of
> play, and this happens on at least three different Nak CR-7A machines (dual
> The squeal is a rather constant tone in amplitude and frequency (2 kHz or
> so is a guess). The decks have even stopped themselves in some instances.
> The squealing in some instances has stopped when I stopped the deck,
> remove the cassette from it for inspection, replaced, and played again.
> But, only to likely start again a little later.
> Tapes have been fast forwarded and rewound before being played. I believe
> the squealing has happened when the tape is packed even better, e.g. after
> a play on one side (which didn't have noticeable issues). But play of the
> first side may not have been monitored very closely by personnel, so don't
> give that all too much weight.
> I've occasionally seen conical wrapping at the outside of the pack (the
> outside 1/8" or so, thinking radially).
> I've transferred some of these tapes to new Maxell shells, removed
> friction sheets in the original shells, removed pressure pads in the
> original shells, loosened case screws in both shells, threaded tape on the
> inside (instead of outside) of the posts near the cassette shell rollers in
> the Maxell shell.
> I checked W/F specs on all machines. They are okay, or just out of spec,
> which does not concern me here (yet).
> The best I've done is maybe reduced the amplitude and regularity of the
> squealing with playback of one tape I recall, but I haven't gotten rid of
> My current belief is that we have lubricant issues, and I'm off to
> read/reread everything I can find in old emails from Richard Hess, Marie
> O'Connell, Steve Smolian that I saved for future reference, like the ones
> I've forwarded below.
> I'd be happy to hear anything else someone may have to offer. Even moral
> support! ;-D Thanks again for your interest.
> Best wishes,
> Karl F.
> Karl Fitzke
> Audio Engineer
> Macaulay Library
> Cornell Lab of Ornithology
> 159 Sapsucker Woods Road
> Ithaca, NY 14850
> [log in to unmask]
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