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Re: [ARSCLIST] Re print-thru - tails out
> I've been told by at least one person who worked at
> Ampex that one of the reasons that German made tapes
> don't "ride up" on the tape pack (and therefore don't
> require a top reel flange) is that the oxide side isn't
> as highly polished as is common with American brands.
> The rougher surface traps less air, so the wrap settles
> down immediately without floating above the previous
> wrap. It's that floating that is the major cause of
> tape not packing evenly on fast wind.
See the following email from MRL President Jay McKnight:
Subject:Country Laning, was Re: [AMPEX] Back Coating. When and why?
Date:Tue, 17 Feb 2009 17:29:25 -0800
From:Jay McKnight <mrltapes@xxxxxxxxx>
Organization:Magnetic Reference Laboratory (h)
To:Goran Finnberg <ampex@xxxxxxxxxxxxx>
References:1 , 2 , 3 , 4
Tuesday, February 17, 2009, 3:53:10 PM, Goran Finnberg wrote:
GF> Kurt US Recording:
>> back coated, with the intended purpose to reduce
>> static buildup and to allow a better
>> tape pack on library wind or even high speed wind.
GF> Sorry no for the: Allow better tape pack when winding thing.
We at Ampex first saw backcoated tape (from AGFA or BASF) in the later
1950s. It high-speed wound really well, and we assumed that it was
because of the backcoating, and that American tapes wound poorly
because of the air being forced out at wind speeds causing the tape to
get pushed up and down randomly. But we later found that the problem
with the American tape was simply that they were not slit straight, and
the AGFA (BASF?) tapes were slit straight.
You can prove this for yourself: Fast wind an American roll of tape.
Take a pencil and mark the reel flange where the tape has "popped" up
and down. Then rewind and forward wind again. You will find that the
"popups" are *in the same places* that they were before. So it must be
(at least mostly) in the slitting.
Do it with an AGFA or BASF roll. You'll see a flat pack.
GF> Uneven wind is due to country laning as shown by a pdf from MRL.
See it at:
Magnetic Reference Laboratory, Inc
The Mastering Room AB
Learn from the mistakes of others, you can never live long enough to
make them all yourself. - John Luther