Mark,
I*ve heard Nadja speak at both AES and ARSC - thank you for that reminder!
~ Eric
On 1/29/16, 5:44 PM, "Association for Recorded Sound Discussion List on
behalf of Hood, Mark" <[log in to unmask] on behalf of
[log in to unmask]> wrote:
>Nadja Wallaszkovits has presented some research (at both the AES and ARSC
>conventions) that she and her colleagues at the Vienna Phonogrammarchiv
>have done to reconstitute the mechanical integrity of catastrophically
>degraded acetate-based tapes. The results were dramatic, physically and
>sonically. Perhaps for intellectual property reasons, they have not yet
>fully revealed the details of the chemistry and workflow of this process,
>but it might be worthwhile for you to contact her directly to see if they
>have any insights or suggestions.
>
>Best,
>Mark
>
>Mark Hood
>Associate Professor of Music
>Department of Recording Arts
>IU Jacobs School of Music
>
>
>
>
>
>
>On 1/29/16, 7:13 PM, "Association for Recorded Sound Discussion List on
>behalf of Eric Jacobs" <[log in to unmask] on behalf of
>[log in to unmask]> wrote:
>
>>We have a 1/4-inch open reel tape (TDK Synchrotape ca 1966 Japanese
>>stock)
>>that is quite literally disintegrating and cannot hold any tension. The
>>very slightest amount of tension causes the tape to snap. The tape
>>cannot
>>even hold a leader without snapping. We易ve turned the tape tension way
>>down
>>on our Studer A820, but it can易t be pulled through the transport without
>>snapping.
>>
>>The tape is heavily curled along the edges (only the center 25% is flat)
>>and
>>is anything but straight from exposure to presumably high temperatures
>>over
>>the past 50 years. The outer wraps have bonded to each other. We can
>>deal
>>with the edge curl and the age-induced country-laning by using a custom
>>mechanism that gently increases the tape wrap around the PB head (forces
>>the
>>tape flat) and additional edge guides fore and aft of the PB head that
>>keeps
>>the tape centered on the head. We can even separate the outer wraps,
>>albeit
>>in 1-inch segments that would need to be spliced together 〝 this seems
>>like
>>a bad idea, but I don易t see any other choice if we want to get past the
>>outer wraps.
>>
>>But it易s the fragility of the tape (lack of tensile strength) that is the
>>central issue. If it were possible to 昆back昌 the tape, it might keep it
>>from snapping. But how do you efficiently and reliably 昆back昌 1200 feet
>>of
>>tape that snaps with the slightest bit of handling? And what do you back
>>the tape with? Splicing tape? It might be easier to apply backing to the
>>centerline of the tape rather than the full width because of tape
>>shrinkage
>>and edge distortion, but then the resulting tape pack would probably be
>>quite poor, especially if the backing doesn易t stack precisely on top of
>>the
>>previous wrap. Also, a narrow backing (like cassette splicing tape) may
>>or
>>may not affect the ability to force the tape flat at the PB head 〝
>>essential
>>for a quality transfer.
>>
>>Looking for ideas and suggestions.
>>
>>~ Eric
>>
>> Eric Jacobs, Principal
>> The Audio Archive
>> 1325 Howard Ave, #906, Burlingame, CA 94010
>> Tel: 408-221-2128 | [log in to unmask]
>> www.theaudioarchive.com <http://www.theaudioarchive.com/>
>
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