The Acoustic Guitar Forum

Go Back   The Acoustic Guitar Forum > General Acoustic Guitar and Amplification Discussion > RECORD

Reply
 
Thread Tools
  #1  
Old 01-02-2019, 12:17 PM
Bob Womack's Avatar
Bob Womack Bob Womack is offline
Guitar Gourmet
 
Join Date: Dec 2000
Location: Between Clever and Stupid
Posts: 26,989
Default Tape baking gone bad

I've spoken of baking tape on the forum before, HERE and HERE. The basic issue is that tapes are self-destructing and the only way to resurrect them is to literally bake them at low heat (130') for three hours. The fellow who has been doing my baking for me has been having trouble with the fumes from the baking process asphyxiating him so he bought a toaster oven so he could bake the tapes out on his veranda. Here is the result of his first run on a tape with a plastic reel:


Lovely, huh? Like that upper flange? I've just transferred the tape. There's lots of creasing and warpage to the tape causing wow. flutter, and scrape flutter. The creasing could be ironed out (if I had the time and this was a priority job) but the warping is causing major vertical mis-tracking across the head stack and I don't know of any way to remedy that.

Bob
__________________
"It is said, 'Go not to the elves for counsel for they will say both no and yes.' "
Frodo Baggins to Gildor Inglorion, The Fellowship of the Ring

THE MUSICIAN'S ROOM (my website)
Reply With Quote
  #2  
Old 01-02-2019, 12:22 PM
Brent Hahn Brent Hahn is offline
Registered User
 
Join Date: Jul 2017
Posts: 3,065
Default

Warping -- as in, the tape used to be straight but now it's curvy, so it slides up and down over the heads? Never heard of that.
__________________
Originals

Couch Standards
Reply With Quote
  #3  
Old 01-02-2019, 12:35 PM
Al Acuff's Avatar
Al Acuff Al Acuff is offline
Charter Member
 
Join Date: May 2017
Location: Santa Fe, New Mexico
Posts: 758
Default

AFAIK a convection oven is the correct tool for baking old tape. That’s what we used when I worked at a mastering facility. Never had a problem.
__________________
Al Acuff
Al's Folk Music Blog
Alan Acuff Music
Reply With Quote
  #4  
Old 01-02-2019, 12:36 PM
Bob Womack's Avatar
Bob Womack Bob Womack is offline
Guitar Gourmet
 
Join Date: Dec 2000
Location: Between Clever and Stupid
Posts: 26,989
Default

Yup. Hold the tape up in a line and it looks a little like a snake. I assume it is from contact with the near-molten "fronds" that developed from the upper flange. This is the thinner, long play Ampex 406 tape. I wonder if the thicker, sturdier Ampex 456 mastering tape would have done it?

Incidentally, this about our fiftieth project in the series. That's pretty good odds for rescuing forty year old tape but it's a shame nevertheless.

Bob
__________________
"It is said, 'Go not to the elves for counsel for they will say both no and yes.' "
Frodo Baggins to Gildor Inglorion, The Fellowship of the Ring

THE MUSICIAN'S ROOM (my website)
Reply With Quote
  #5  
Old 01-02-2019, 01:23 PM
Brent Hahn Brent Hahn is offline
Registered User
 
Join Date: Jul 2017
Posts: 3,065
Default

Quote:
Originally Posted by Al Acuff View Post
AFAIK a convection oven is the correct tool for baking old tape.
But if you want that savory browning and bubbling, you need the toaster oven if not a full-on broiler.
__________________
Originals

Couch Standards

Last edited by Brent Hahn; 01-02-2019 at 01:41 PM.
Reply With Quote
  #6  
Old 01-02-2019, 01:33 PM
Edgar Poe Edgar Poe is offline
Registered User
 
Join Date: Aug 2017
Posts: 642
Default

Sounds to me like the tapes have been wound too tight and sat too long.
I advise rewinding tapes periodically and wind them slightly loose. If wound too tight, you can also get two problems, layer to layer transfers, and layer to layer adhesion. Neither is good. If you can't push on the edge of the wound tape and compress it slightly, it's too tight. I know smooth wound flat sided reels of tape look cool, but they are not always wound right and can be troublesome.

Ed
__________________
"Quote The Raven, NEVERMORE !"
Reply With Quote
  #7  
Old 01-02-2019, 01:38 PM
Edgar Poe Edgar Poe is offline
Registered User
 
Join Date: Aug 2017
Posts: 642
Default

Quote:
Originally Posted by Bob Womack View Post
Yup. Hold the tape up in a line and it looks a little like a snake.

Bob
Is this looking on at the flat edge or thin edge of the tape ? If from the thin edge, that can be from being wound too tight. The tape actually stretches, and when relaxed it springs back and causes warp. Which can cause a warble sound.

Ed
__________________
"Quote The Raven, NEVERMORE !"
Reply With Quote
  #8  
Old 01-02-2019, 01:46 PM
Bob Womack's Avatar
Bob Womack Bob Womack is offline
Guitar Gourmet
 
Join Date: Dec 2000
Location: Between Clever and Stupid
Posts: 26,989
Default

Quote:
Originally Posted by Al Acuff View Post
AFAIK a convection oven is the correct tool for baking old tape. That’s what we used when I worked at a mastering facility. Never had a problem.
Yep. I asked the producer in charge to get an air drying oven but he tried this instead.


Bob
__________________
"It is said, 'Go not to the elves for counsel for they will say both no and yes.' "
Frodo Baggins to Gildor Inglorion, The Fellowship of the Ring

THE MUSICIAN'S ROOM (my website)
Reply With Quote
  #9  
Old 01-02-2019, 02:05 PM
Bob Womack's Avatar
Bob Womack Bob Womack is offline
Guitar Gourmet
 
Join Date: Dec 2000
Location: Between Clever and Stupid
Posts: 26,989
Default

Quote:
Originally Posted by Edgar Poe View Post
Sounds to me like the tapes have been wound too tight and sat too long.
I advise rewinding tapes periodically and wind them slightly loose. If wound too tight, you can also get two problems, layer to layer transfers, and layer to layer adhesion. Neither is good. If you can't push on the edge of the wound tape and compress it slightly, it's too tight. I know smooth wound flat sided reels of tape look cool, but they are not always wound right and can be troublesome.

Ed
These tapes were wound onto their reels with pack mode, meaning about twice playback speed. The rest of the tapes are nicely packed. Before I play them back, if they are tails out, I rewind them in pack mode to yield a good pack and then play them back. If they are heads I wind them to the end in pack mode and then rewind them in pack mode. In this particular case, when I saw the damage, I chose to pack at playback speed and to record as packing as a precaution.

They also were excised from a tape library after twenty years and thrown away, only to be saved by an obsessive librarian apparently, and chucked into casual storage. Fifteen years later they were offered for archive, and I am getting the results - untouched probably since recorded in 1978.
Quote:
Originally Posted by Edgar Poe View Post
Is this looking on at the flat edge or thin edge of the tape ? If from the thin edge, that can be from being wound too tight. The tape actually stretches, and when relaxed it springs back and causes warp. Which can cause a warble sound.

Ed
This is looking at the flat side of the tape, as it passes through the headblock. On this tape only you can actually see the tape move up and down in relation to the vertical plane of the head stack. So there's an actual vertical warp. As I played the spool I could see that the curvatures matched the locations of the globbed upper flange as they relaxed onto the tape. The rest of these tapes have been well-packed and have come to me in good condition.

Honestly, I wish I were working with the Ampex ATR102s I used to work with instead of Sony APR5003s. Due to having all servo motors and a servo lock system they handled tapes better. But these are excellent Sony console professional mastering machines.

Bob
__________________
"It is said, 'Go not to the elves for counsel for they will say both no and yes.' "
Frodo Baggins to Gildor Inglorion, The Fellowship of the Ring

THE MUSICIAN'S ROOM (my website)
Reply With Quote
Reply

  The Acoustic Guitar Forum > General Acoustic Guitar and Amplification Discussion > RECORD

Thread Tools





All times are GMT -6. The time now is 04:12 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright ©2000 - 2022, The Acoustic Guitar Forum
vB Ad Management by =RedTyger=