Very interesting discussion. Fred, what are your opinions on which
machines are the "great reproducers"?
Thanks,
John Haley
On Thu, Mar 27, 2014 at 9:39 AM, Fred Thal <[log in to unmask]> wrote:
> Hello Tom Fine,
>
> Let me comment on some of your good observations, which I have pasted-in
> below.
>
> > The idea of "playing vintage tapes on vintage tape machines" is a mute
> point nowadays.
>
> I wish this were so, but sadly it isn't. Witness that a fragile (and
> obviously irreplaceable) Sinatra master was destroyed just last year,
> simply by being played back on the wrong equipment. The machine in
> question is regarded by some as being very modern, in relative terms.
>
> Sadly, there are many such cases, although understandably not widely
> reported.
>
> By the way, couldn't we argue that all analog tape machines could be
> termed vintage today?
>
> Wouldn't it be more useful to define some of the basic tape transport
> architecture classes that distinguish these machines from one another,
> and then classify the various machines accordingly? For example:
> Recorder/reproducer or reproducer? Servo constant-tension or constant
> torque? Servo-capstan or hysteresis synchronous capstan? Force-guided
> or precision guided transport path? Pin lifter or roller lifter at
> headblock?
>
> For practical examples of what these differing machine architectures
> might mean in historic transfer work today, consider an acetate master
> that has the oxide layer falling off. Or a mylar master that is
> exhibiting soft binder syndrome.
>
> Would mounting either of those master reels and re-winding on a
> transport with fixed pin lifters be responsible practice?
>
> What about edge-forced guidance through a headblock? Or needlessly
> pulling the fragile tape over an erase and then a record head? First,
> do no harm.
>
> > By the time of all the later-generation professional tape machines,
> > things like speed stability and scrape-flutter were well understood,
> > so playback was more precise.
>
> Yes, achieving satisfactory speed stability was in many cases
> accomplished by adopting constant-tension and servo capstan designs.
>
> But as I see it, the matter of scrape flutter is not so simple.
>
> The project leader for the Ampex ATR-100 certainly understood scrape
> flutter, but he knew that precision guidance through the transport
> would add tremendously to the manufacturing cost. Further, he
> correctly understood that you could not insist that customers use only
> certain brands of tape. (Especially if these were tapes not
> manufactured by Ampex!) So forced guidance through the headblock was
> designed in. It was a huge scrape flutter generator, yet regarded as a
> necessity. And it remains difficult to argue that his approach was
> wrong.
>
> > It adds up and it's audible.
>
> Correct. Scrape flutter is audible and the components of flutter add
> vectorially. This makes the choice of the reproducer quite important,
> exactly as you have observed. We have been saying (for about 20 years
> now) that ideally, the reproducer's flutter contributions should be
> lower than the recorded flutter on the tape, by an order of magnitude.
>
> I hope that re-issue producers always first listen to a historic
> master played back on an ultra-low flutter reproducer, before
> committing to trying to fix something with subsequent processing in
> the digital domain. People are often surprised at what can be
> retrieved from an old tape when it's played back on a great
> reproducer.
>
> Fred Thal
> ataestuder.com
>
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