>I have identified this as the reel being part of a Van de
>Graff generator. When the voltage exceeds the breakdown of
>the air gap, tick, there is a spark. The trick is to ground
>the reels. Some reel tables are painted with an insulating
>coating. I have used a variety of tricks to ground the
>reels.
>
> I recall seeing this on ReVox A77s and Studer A807s, but I
> can't recall seeing this on a Studer A80 or A810, nor a
> Sony APR-5000.
>
> Cheers,
>
> Richard
>
>> On Thu, Feb 3, 2011 at 11:28 AM, John
>> Dawson<[log in to unmask]> wrote:
>>> Does anyone have any tips for avoiding pops caused by
>>> static elctricity during playback of analog open reel
>>> tapes? I only encounter this problem in the winter when
>>> the heat has been running and it is very dry. Bringing
>>> some sort of humidifier into the studio is not ideal.
>>> This winter, I haven't had this problem until I started
>>> transferring tapes with long playback times. Right now I
>>> am working with 1800' 1 mil based polyester tape played
>>> back on a Studer A810.
>>>
>>> Thanks,
>>> John Dawson
I had a terrible problem with this last year (on an A-80RC),
which got progressively worse. I figured it was a problem
with the head, so I tried replacing the caps on the
headblock and the wires from it. Didn't help. I finally took
it to Tony at IEM (http://www.iemmag.com/About_Us.html). He
determined that the ground to one channel of the playback
head was faulty, and used some kind of conductive paste to
fix it. This almost totally eliminated the problem, but not
entirely. I still get random spikes on either channel,
perhaps two or three in a 30min reel, where there were
dozens before.
I have found that Wavelab is great for repairing those
spikes. I use the global analysis (error tab) to identify
them, and the Waveform Restorer to zap 'em.
The reel-grounding idea seems interesting, but how do you
ground a plastic reel?
-Matt Sohn
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