[Vintage-Audio] Scotch Audio Tape Variations

Tue Feb 22 23:49:26 EST 2005

Looking at this from a different angle, what color is the oxide side of the
tape? The brownish red or the grayish black?

----------
From: Gerry Steffens <gsteffens at pitel.net>
To: 'Vintage home and professional audio equipment from 1975 back'
<vintage-audio at mailman.qth.net>
Subject: RE: [Vintage-Audio] Scotch Audio Tape Variations
Date: Tuesday, February 22, 2005 11:06 PM

Sorry, there is no number on any of the boxes.  The literature only refers
to "Scotch" Brand CLASSIC.   This appears the only designation and it is
used over and over.  It is written with the word classic all in capital
letters, Scotch capitalized and in quotes and Brand capitalized.  It is 1
mil, 1800 feet and back coated.  This Classic tape is in black boxes that
have padded front covers that are attached along the back hinge area and are
identified by chrome appearing lettering in the upper right, front corner.
The boxes also have a plastic insert inside that provides a circle into
which the reel is placed, as opposed to just a round reel in a square box.

The tape without back coating is also "Scotch" Brand CLASSIC but it is
merely in a plain black box, no circular insert, no padded cover, no scotch
plaid or the old red, white and blue and is 1 and 1/2 mil, 1200 feet.

Cheers from Minnesota,
Gerry

Collecting & Restoring since 1959
Gerald Steffens P.E.
Oronoco, MN

-----Original Message-----
From: vintage-audio-bounces at mailman.qth.net
[mailto:vintage-audio-bounces at mailman.qth.net] On Behalf Of Duane B.
Fischer, W8DBF
Sent: Tuesday, February 22, 2005 9:35 PM
To: Vintage home and professional audio equipment from 1975 back
Subject: Re: [Vintage-Audio] Scotch Audio Tape Variations

Gerry, 	

Can you please tell me the Scotch tape numbers, such as 150, 207, 227 etc.?

Thank you.	

Duane Fischer, W8DBF	

----------
From: Gerry Steffens <gsteffens at pitel.net>
To: 'Vintage home and professional audio equipment from 1975 back'
<vintage-audio at mailman.qth.net>
Subject: RE: [Vintage-Audio] Scotch Audio Tape Variations
Date: Tuesday, February 22, 2005 8:22 PM

I have three different styles of Scotch Classic on 7 1/2 inch reels in
original high end plastic boxes.  One has no back coating, two styles do
have and I don't know which is later but following are the two bulleted
descriptions on the circular inserts in the formed portion of the tape box:

Exclusive POSI-TRAK backing improves mechanical handling for longer tape
life and even tape wind

The other back coated tape insert reads as follows: 

Exclusive POSI-TRAK backing improves mechanical handling for longer tape
life and even tape wind while reducing print through

This might lead one to believe that they might have added the back coating
for traction and durability purposes and then realized that print through
was also reduced (because of thickness changes) and then laid claim to that
too.

Note that of my back coated tapes, several have turned to a gummy mess and
have been trashed.  As I remember all of these were Scotch but I am not
certain.

All of these tapes are 1800 foot, 1 mil tapes.

I have another insert I believe to be from Quantegy Grand Master Studio
Master Audio Tape.  This insert also mentions the reduction of print through
attributed to the back coating in addition to a reduced wow & flutter due to
better traction and a more "controlled" tape movement.  This insert is in
the Quantegy box but has no marking to confirm it belongs there.

Cheers from Minnesota, 

Gerry

Collecting & Restoring since 1959
Gerald Steffens P.E.
Oronoco, MN

-----Original Message-----
From: vintage-audio-bounces at mailman.qth.net
[mailto:vintage-audio-bounces at mailman.qth.net] On Behalf Of Sheldon Daitch
Sent: Tuesday, February 22, 2005 10:56 AM
To: Vintage home and professional audio equipment from 1975 back
Subject: Re: [Vintage-Audio] Scotch Audio Tape Variations

I never heard that the backcoating was to reduce print-through, although the
thicker the base stock, and the back coating would add to that, the lower
the
print-through, in theory.

I always thought the back coating was to reduce static in fast forward and
fast
rewind operations. and at least one site:

 http://www.videomaker.com/scripts/article.cfm?id=1540

seems to back that up:

"Many years ago, the 3M company added an extra layer to their audio and
videotapes. They applied a graphite compound to the base side of the tape,
away
from the magnetic coating. Their reason for doing this was to lower static
electrical charges (which build up during fast wind/rewind) and improve the
durability of the tape--especially important for editing. Their
studio-quality
audio tapes and broadcast videotapes were soon known by their dull black
backside appearance.

Today, some tapes are back-coated and some are not. While the advantages of
backcoating were (and still are) real, improvements in tape manufacturing
have
made it a matter of choice for tape makers, and not so much a big deal to
you,
the user."

I have a Teac A-7030 deck and I have problems with the back coated tapes,
when I
leave the auto rewind mode on.  The rewind mode uses a split sensor in the
supply reel idler arm, the two pieces of the sensor are insulated, and when
a
metallic section of tape shorts out the two pieces, it sends the deck into
the
rewind mode.  SInce it relies on a small voltage across the two sensor
points,
the voltage causes some "static" in the playback side, no doubt due to the
conductivity of the back coating.

Sheldon

Gerry Steffens wrote:

> Not sure of the difference between the two Scotch tapes but the back
coating
> is there to reduce the level of print through.  When tapes are wound and
> remain that way for longer (or even shorter) periods of time the magnetism
> from one layer will "print through" to the next layer.  This is
particularly
> true of loud passages.  Minimizing print through was one reason we left
> tapes tails out at the radio station when I was a DJ while in college a
> little over thirty-five years ago.
>
> Gerry
>
> Collecting & Restoring since 1959
> Gerald Steffens P.E.
> Oronoco, MN
>
> -----Original Message-----
> From: vintage-audio-bounces at mailman.qth.net
> [mailto:vintage-audio-bounces at mailman.qth.net] On Behalf Of Duane B.
> Fischer, W8DBF
> Sent: Saturday, February 19, 2005 5:57 PM
> To: vintage-audio at mailman.qth.net
> Subject: [Vintage-Audio] Scotch Audio Tape Variations
>
>
> Hi All,
>
> What is the 'real' difference between the seven inch reels of Scotch autio
> tape
> #207 and #227?
>
> I weighed each on a postal scale, as I thought the #227 felt heavier to
me.
> The
> #207 weighed 13.5 ounces and the #227 was just under 14 ounces.
>
> Both appear to be very high quality, the #227 I am positive is commercial
> grade,
> as it has the black/gray oxide.
>
> Additionally, what was the thinking in the 'back coating" of audio tapes?
> The
> reddish oxide on one side and black on the other.
>
> Thank you.
>
> Duane W8DBF
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **

_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com ** 

_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com ** 
_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com ** 

_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com ** 