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Back in early 2014, I sent Charlie Richardson an old Ampex 7.5IPS alignment tape, which is on Ampex 
406 tape, circa 1970. The tape was definitely sticky-shed, in fact the first couple of layers I 
wound out by hand pulled oxide to the adjoining backing layer. Richardson treated the tape with his 
"Rezorex" process, which apparently uses a chemical peel to remove the back-coat layer, which 
Richardson contends is the source point of sticky-shed. I transferred the tape in May 2014 with no 
problems, then put it on a shelf in ambient metro-NYC indoor environment. That first playback was on 
an Ampex AG-440B. I just rewound and played the tape again, this time on an Ampex 352. Still no 
sticky-shed evidence, and the audio was fine (test tones were 10dB below reference tone, for the 
most part, azimuth tones allowed stable adjustment). Richardson had left a little bit of the end of 
the reel with the back-coat still on, and that tape was solidly sticky-shed. I will keep on playing 
this tape once a year to see if it goes sticky again.

I think a more scientific test of this process would require sacrifice of both a sticky-shed test 
tape and a high-fidelity music recording on sticky-shed tape. Although Richardson wants tapes not to 
have been previously baked and played, which he contends damages the tape, I'd want a reference 
transfer after one bake. Then let the back-coat layer be removed, and do a transfer with the exact 
same equipment and compare both measurements and careful listening, see if the chemical peel does 
any sonic damage. In the case of my old test tape, all I'm saying is that the tones are at the 
announced levels, and this tape could be used in a pinch to align a tape deck, although I'd want to 
bet on a modern MRL tape if it were for anything critical.

One other thing. The tape with the backcoat removed is not as thin as I thought it would be. It 
seems to move through the transport just fine. I didn't observe any obvious edge-curl or 
country-lane motion, and it fast-winds just fine through all the static guides on an older Ampex 
transport.

I'd want to do more testing with very familiar high-fidelity music recordings to make sure the 
process doesn't do any damage to audio, but for at least a year and a half, it does seem to prevent 
a return of sticky-shed's mechanical symptoms.

-- Tom Fine