Thank you for taking on this project. If there is anything I can
contribute from the Left Coast, please let me know.
Three questions immediately come to mind which could lead to some testing:
Why do some audio tape formulations seem to last the test of time and
other formulations are (almost) guaranteed to be SS? Generally, those
tapes that are guaranteed to be SS are much newer formulations.
Does the back-coating of those tapes that are back-coated contribute to
tape degradation? There has been some testing , mostly by Charles
Richardson, that suggests that the back-coating may lead to SS over time.
Why are we now seeing evidence of SS with digital audio (and some DV)
tapes? These formulations and manufacturing procedures are completely
different than analog audio tape.
Corey Bailey Audio Engineering
On 6/1/2016 9:59 AM, Richard L. Hess wrote:
> I am cross-posting this to all three ARSC lists to throw a wide net,
> but PLEASE let's continue the discussion on the main ARSC list or by
> email to me directly, preferably at [log in to unmask]
> Recently, I have been in discussions with a group who has analytical
> equipment that might be useful for analyzing tape degradation, and
> they appear interested in running some tests. We may not need massive
> amounts of testing. A few well-thought out tests may be of immense
> Benoit Thiebaut of the Prestospace project ran a test for my 2008
> paper which presented evidence that there was no loss of lubricant in
> tapes--the lubricant was still there, but yet the tape squealed. This
> led to a test by Ric Bradshaw at the IBM tape lab in Tucson showing a
> low glass transition temperature for a squealing tape (about 8 °C).
> These helped in the understanding of why cold playback and D5
> lubrication both could be used to stop squealing.
> The first step is for all of us to chime in about what we think needs
> to be analyzed.
> Here is the first one:
> I have great concern for the apparent increase in binder-base adhesion
> failure. This is happening with both acetate and polyester base films.
> We should be aware of Tom Fine's conjecture that the dry (and cold)
> storage recommended for (and apparently good for) polyester base film
> tapes may be drying out and damaging acetate base film tapes.
> We should also be aware that Ric Bradshaw has suggested that baking
> tapes may lead to binder-base adhesion failure. And, of course we need
> to remember that one never bakes an acetate tape.
> What do YOU want tested?
> The second step will be to collect samples for analysis. Apparently
> 25-50 mm of material is adequate (smaller can be used). For separating
> tapes both separated and non-separated samples would be useful.
> Metadata is important to understand context and should include as much
> of the following as is known: manufacturer, type, date of manufacture,
> presumed storage conditions over time, any known treatments,
> observations at time of playback, and anything you can think of that
> might be useful.