From: "Richard L. Hess" <[log in to unmask]>
> Hello, Goran,
> A friend of mine (who would rather not be dragged into more
> conversations about this) who worked in the Ampex Standard Tape Lab, and
> who is not part of this list, reported to me that no one could explain
> why, but some cassettes that were recorded would lose high frequencies
> if stored for about a year. The loss was substantial. While Don no
> longer has any notes on this, I have generally found his memory and
> knowledge to be reliable. His recollection is that the 15 kHz loss was
> in the neighbourhood of 10 dB in the worst examples.
> I have grilled him on this, and he is convinced that it happened and it
> was not due to external magnetic fields.
> One theory that was proposed at the time was magnetostriction due to the
> relatively small radii of the guides in the cassettes.
> He used Dragons and other top-end cassette machines in the lab. He was
> responsible for a while for manufacturing Ampex standard "test"
> [calibration] tapes for audio and video.
>
In my own case, I would be cheerfully ignorant of any HF loss on my
long-stored cassettes...! Two serious head injuries and 68 years of age
have cost me not only most of my high-frequency hearing...but also
much of my hearing in general. I hope that within the next couple of
years I can invest in one or two state-of-the-art hearing aids...?!
This is probably why I can be happy with the sound of a ceramic
cartridge whose 1-volt signal can be directly fed into a "Line In"
jack...?!
Steven C. Barr
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