Hi, Abhi and Tim,

Great discussion. The cupping is a real issue, but so is edge waviness.

On the suggestion of Friedrich Engel (retired BASF Historian), I once 
reviewed the only carbonyl iron tape I've ever seen. This was one of the 
first Magnetophon experimental tapes from circa 1935. It was so badly 
cupped that it was like a carpenter's steel tape and could support 
itself extending from the reel.

Hydration was Herr Engel's suggestion, I tried about 24 hours with the 
tape in a pancake form on a support over about an inch of water in a 
sealed container. It ran beautifully and was more like a satin ribbon 
than a tape measure.

HOWEVER, I have repeated that once or twice since with far less success. 
The hydration probably reduces the strength of the tape.

The worst over-hydration I've ever seen was a damp 1-inch Scotch 201 
acetate tape. The acetate had swollen so much that the first half inch 
at the hub had been deformed and the closest layers had been forced 
through the slot of the hub, causing a bump. Of course it was worse on 
the track one side (which was recorded while only about five tracks had 
been used) and the tape had been wound tails out so the pack was tight 
and the first song of the album was most damaged!

I put a pressure pad hard against the head (while adding extra pressure 
to the pinch roller to keep the tape on speed). My hands were very 
cramped a half hour later. Then Paul MacDonald from Cape Breton Island, 
Nova Scotia who is a musician and excellent recording/mastering 
engineer, spent days with it picking out a similar piece of music to 
cover the bumps using Sound Blade software. It turned out beautifully.

If the edges are wavy, then certainly tracks 2 and 3 would be a better 
choice, if the cupping is tamable.

It is such a difficult line to draw between doing no harm to the 
original and capturing the best possible transfer which will likely be 
the last transfer made (unless you really miss the mark). If you are 
doing risky procedures, it is important to inform the clients about the 
problems and risks before proceeding.

Cheers,

Richard


On 2021-11-21 4:55 a.m., Tim Gillett wrote:
> Hi Abhi,
> 
> I suspect your experience with the old acetates is common. When
> brittle they can break easily but at least they break cleanly and
> can  be spliced back together again. The other issue which is common
> is "cupping" on the oxide side. The top and bottom edges of the tape
> are OK on the tape head but the centre section doesnt want to sit flat
> so the sound is often muffled or weak. We can increase the tape
> tension across the head but it risks breaking the tape.  Sometimes
> a temporary felt pressure pad, or small artist's brush, or even a
> fingertip as you did can be used to press the centre section against
> the head.
> 
> The problem you mentioned with the Lafayette acetates could be that
> they were recorded on a Brush Soundmirror machine which only recorded
> in the centre of the tape, leaving the top and bottom edges
> unrecorded. A "cupped" acetate tape is the worst for this as it keeps
> that most important part of the tape off the head. The reason the
> Studer machine didnt play them well is probably that it was an NAB
> half track machine which would have missed the centre part of the
> tape. You're right that tracks 2 and 3 of a quarter track machine
> would read it much better.   Actually a very good playback can be
> obtained from a Soundmirror tape with a four track (four channel) 1/4"
> head  using tracks 2 and 3.
> 
> Best wishes,
> 
> Tim Gillett
> 
> Perth, Western Australia
> 
> ----- Original Message -----
> From: "Association for Recorded Sound Discussion List"
> <[log in to unmask]>
> To:<[log in to unmask]>
> Cc:
> Sent:Sun, 21 Nov 2021 04:58:17 +0000
> Subject:Re: [ARSCLIST] 220V/50Hz 1/4" Open Reel Audio Playback Decks
> 
>   Hi Richard,
>   Wow! You have no idea what it means for a little guy like me to
> contribute to this forum!
>   First, just a very quick background. Although I was born and brought
> up in the U.S., I spent all of my adult and professional life in India
> (I am of Indian origin).
>   I used to work in the recording studio of the Gramophone Company of
> India. It used to be a wholly owned subsidiary of the GC of UK. Later
> it became independent.
>   GC of India has a tape archive with acetates starting from around
> 1955. They are almost entirely EMI tapes and are in excellent
> condition. There’s no problem of brittleness and they play fine on
> A80’s and 807’s.
> 
>   Now I work independently, usually with smaller archives or individual
> collections. The name brand tapes that I get, e.g. Scotch 111 or
> 141, usually play fine on my A807. However, given the tropical
> climate in India and the lack of maintenance of the tapes, warping is
> a frequent problem.
>   A few years ago, I inherited a dozen Lafayette brand tapes from my
> uncle. The tapes were purchased in 1960 and recorded between 1961 to
> 1965.
>   These tapes are mostly brittle. Instead of A807, for most of these
> tapes I had to use an Akai GX-4000D quarter track deck to play half
> track recordings. Yes, I know I broke every rule in the book but I
> couldn't think of any other way.
>   Interestingly, for some of these tapes played on the Akai, I got a
> better playback from tracks 2 and 3 compared to tracks 1 and 4. Of
> course, I had to reverse them on my DAW.
>   A few years ago I got an acetate similar to your Vermont tape. I
> actually had to unwind several hundred feet of tape from the reel,
> somehow thread the tape onto my Akai without any reels on either side,
> and hold my index finger softly against the playback head while
> playing.
>   So, basically, the brittle acetates that I've encountered are due to
> lack of maintenance or a cheap brand of tape.
>   Coming back to Dave's original post, I was thinking to myself when I
> first read it that it might be nearly impossible to find a machine
> that can satisfy all of his conditions. But, then, I don't have any
> experience with the ATR 100 or APR-5000.
> 
>   Best wishes,
>   Abhi (short for Abhimonyu)
>   ------------------------------------------
> 
>   Abhimonyu DebAudio Consultant and Digitization
> Specialisthttps://www.linkedin.com/in/abhimonyudeb
> 
>   On Saturday, 20 November, 2021, 09:53:59 pm IST, Richard L. Hess
> <[log in to unmask]> wrote:
> 
>   Hi, Abbimonyu,
> 
>   This issue comes up in regard to many different machines. When I had
> my
>   A80s, I used them for acetate tapes on a regular basis. I haven't
> used
>   an A807 for a long time (as I preferred the A810 over the A807 for
> many
>   reasons, and the A80 over the A810).
> 
>   In many respects, I think that the Sony APR-5000 is the gentlest of
> the
>   list I posted. On the  other hand, I had no bad feedback from the
> two
>   A807s (refurbished by Roger Ginsley) that were sold into an archiving
> 
>   project in Pakistan to use alongside their Tascam BR-20s (which I did
> 
>   not suggest for the current project because many versions were not
> made
>   with power supply voltage selection).
> 
>   However, to answer Tim Gillette's rephrasing of the question, we
> might
>   consider machines that start the capstan motor when going into play
> so
>   you are not banging the stopped tape into the full-speed capstan. The
> 
>   Sony APR-5000 works that way and mutes the audio for a short period
> of
>   time at startup.
> 
>   You weren't missing something and it is good that you posted. Perhaps
> I
>   didn't provide enough weight to that criteria.
> 
>   I'd be interested in hearing more about the fragile acetate tapes
> that
>   you encounter as I've been surprised at how well the Scotch 111 and
>   Audio Devices acetate tapes have held up. I've even been pleased with
> 
>   the paper tapes I've transferred as well. The only really fragile
>   acetate tape I've come across was one that sat behind a wood stove
>   through several Vermont winters. One face was welded together and
> broke
>   on ever rotation of the supply reel.
> 
>   The one thing that seems to fail for me are splices onto paper
> leader. I
>   have to remake all those splices after baking in many instances, but
>   that's with back-coated polyester tapes.
> 
>   Cheers,
> 
>   Richard
> 
>   On 2021-11-19 8:41 p.m., Abhimonyu Deb wrote:
>   > Given the notable list of people who have replied so far, normally
> I would keep my mouth shut.
>   > However, I do think everyone is missing an important point.
>   >
>   > Dave mentions that the machine should be able to play fragile
> acetate tapes. The A80’s, 807’s and Otari 5050’s that I’ve
> worked with would fail miserably here unless I’m missing something.
>   > Abhimonyu Debhttp://linkedin.com/in/abhimonyudeb
>   >
>   >
>   >
>   > On Saturday, November 20, 2021, 6:42 AM, James Perrett
> <[log in to unmask]> wrote:
>   >
>   > On Sat, 20 Nov 2021 at 00:55, Richard L. Hess
> <[log in to unmask]>
>   > wrote:
>   >
>   >>
>   >> Long ago, a company I think called
>   >> "DarkLab" in Germany made EIA to DIN adapters out of plastic.
>   >>
>   >>
>   > They still make them and sell them on Ebay. I bought some a few
> months ago
>   > but haven't used them yet.
>   >
>   > James.
>   >
> 
>   --
>   Richard L. Hess                  email:
> [log in to unmask]
>   Aurora, Ontario, Canada                            647
> 479 2800
>   http://www.richardhess.com/tape/contact.htm
>   Track Format - Speed - Equalization - Azimuth - Noise Reduction
>   Quality tape transfers -- even from hard-to-play tapes.
> 
> -------------------------
> Email sent using Optus Webmail
> 

-- 
Richard L. Hess                   email: [log in to unmask]
Aurora, Ontario, Canada                             647 479 2800
http://www.richardhess.com/tape/contact.htm
Track Format - Speed - Equalization - Azimuth - Noise Reduction
Quality tape transfers -- even from hard-to-play tapes.