Re: [ARSCLIST] Best practice: mixed acetate and polyester reels with sticky shed

[George Brock-Nannestad <pattac@xxxxxxxx>]

From: Patent Tactics, George Brock-Nannestad

Eric Jacobs wrote:

> I have Scotch 201 (acetate base) and Scotch 206 (polyester base,
> back coated) in two dozen alternating segments.  The Scotch 206 
> is very sticky.
> 
> I was able to separate the 201 and 206 so that the 206 could be 
> baked apart from the 201 (not to be baked).  The STUDER A820 has 
> only rolling contact when spooling, and I set the tensions very 
> low and the library winding speed at 3 meters/sec.  This allowed 
> spooling of the sticky segments, which had to be done prior to
> baking in order to separate the polyester from the acetate.

----- lovely to hear about good equipment for the purpose

> 
> So here are my thoughts and questions:
> 
> 1.  For future playback, would it be better to splice all the 
>     polyester together, each segment separated by leader, and the 
>     leaders annotated as to the order of the segments?  Ditto 
>     for the acetate.  Pros: Future baking becomes vastly simpler.  
>     Downside: the non-sequential segment order needs to be 
>     documented in the metadata, in the filenames of the preservation 
>     masters, and possibly annotated on the tape itself (on the 
>     segment separation leaders).

----- I would definitely recommend this option. The only way that you can get 
a preservation master is by performing the separation that you described 
above, so you have the option between no preservation master and a re-
assembled one. The original tape only serves to authenticate, and it is now 
vastly more accessible. Obviously this generates metadata. The annotation on 
the tape itself (the leaders) will be an interesting exercise, because you 
need arrows to point to which part you mean. You would not want to reverse a 
piece of tape in the process.

> 
> 2.  Or would it be better to re-assemble the reel in its 
>     original segment order (alternating polyester/acetate)?
>     Pros: we preserve the original order of the tape.  Cons:
>     someone in the future may have to repeat the exercise of 
>     separating the segments yet again for baking?

----- the only problem lies in the authentication: the tape as found 
undoubtedly uses the pieces in the order originally planned, if the splices 
hold up. However, irrespective of whether you use (1) or (2) the pieces have 
been separated in the process, and we only have your assurance that the 
pieces are now in the same order according to (2). If we trust this 
reassembly we could just as well trust that you have brought the two types of 
tape in the order that you yourself describe in the metadata relating to (1). 
But there is no doubt that some authenticity, some indubitable traceablility, 
has been lost in the process. But this way, the surviving tape obtains more 
than mere symbolic value: we get access to the content.

> 
> 3.  I prefer to insert leader between the segments when there is
>     azimuth variation between the segments, as it allows for 
>     easier identification of each segment and cueing each 
>     segment for individual azimuth adjustment (thank goodness
>     for calibrated azimuth adjusters).  Cons: you double the
>     amount of splices in the tape pack.

----- I really enjoyed reading this: this means that you would do it, even if 
the two types of tape did not need different baking and separation per se. 
Splices at an angle serve as a primitive sort of very quick cross-fade - how 
do you deal with this? And the preservation copy you provide would be a-
historical as reproduction goes, because now we have a maximum of high 
frequencies that we did not have ever before. But that is no different from 
extracting sound that was not reproducible on early mechanical reproducers 
from early mechanical recordings.

> 
> To date, I generally perform (2) above - especially if the polyester
> segments do not require baking.  I often get Scotch 201 and Scotch 
> 176 in combination, and this is usually in good shape (ie. no baking
> required).  I perform (3) if there is variation in the azimuth between 
> polyester and acetate segments.
> 
> Just today I was wondering if (1) above would be a better approach
> when dealing with sticky shed in a mixed polyester/acetate reel?
> Odds are, anyone who will attempt to play such a sticky tape 
> in the future will have to go through the exact same exercise of 
> separating and baking.  So why not leave things in a better state 
> for the next audio preservation engineer?

----- I think that your reasoning is sound! I vote for (1). And I would like 
to see convincing arguments in support of (2). And, furthermore, it is my sad 
view that only if the tape in question features in a multi-million court case 
will it ever be played again.

Kind regards,


George