The Acoustic Guitar Forum

The Acoustic Guitar Forum (https://www.acousticguitarforum.com/forums/index.php)
-   RECORD (https://www.acousticguitarforum.com/forums/forumdisplay.php?f=43)
-   -   Analog! The sights, the sounds, the smells... (https://www.acousticguitarforum.com/forums/showthread.php?t=513559)

Bob Womack 06-13-2018 08:55 AM

Analog! The sights, the sounds, the smells...
 
I just started a new project at the studio: digitally archiving and mastering analog recordings of a TV program from the '70s. Someone found the archive of 1/4" tapes and we are bringing them back. A colleague bakes the tapes for two hours in an oven and I then transfer them to a DAW and master them. There are often breaks of months between analog projects these days o I can forget what I used to experience during the many years of analog recording, so sessions like these are a great reminder.

The first thing you are reminded of is the sounds. You flip the switch on the front panel and a relay inside kicks. Clunk. These tape decks were large, complicated electro-mechanical wonders, and they required cooling fans. As I recall this one had two. Then shifting from play to wind or stop required solenoids and physical brakes. Ka-clunk. There's no question why we put all the gear in a separate machine room and used remotes at the console. People used to call the long, narrow machine rooms "zeppelin hangars."

https://scontent-iad3-1.xx.fbcdn.net...5c&oe=5B784F17

The next thing you are reminded of is the cleaning. Hygiene is everything. First you wash your hands and then the machine. A bit of dirt a fraction of the width of a human hair on a head will cause dropouts or at the least a loss of high-end frequency response, so you keep the gear clean enough to eat off of. In fact, it doesn't matter whether or not the gear looks clean, you clean it before and after you use it. After as a courtesy to the next guy, though he will likely clean it as well. Before, because it is your professional reputation is on the line with every second or record or playback. We are using industrial Isopropanol here, and both technical swabs and Techwipes. Then, depending on hours in use, you demag the tape path as well. Next you set up the machine to the tape you are going to use. We got by that often by buying ridiculously large lots of tape from the same batches, thus obviating the need for re-EQing and biasing. However, a tape from another house demanded the full Monty.

Next you are reminded of the waiting that analog recording entailed. A tape that has been stored for a while has to be rewound and repacked to protect it from stretch and to give it every chance to playback smoothly. This tape is thirty years old Ampex 407 stock and irreplaceable so I used pack mode (about 3x playback speed) both directions to get a nice, smooth pack. Meanwhile you are treated to the unique smell of tape oxide wafting off the deck. It is an interesting, musty smell, but it brings back the beginning of my career immediately and intensely.

Just winding such an old tape, even having been baked, even wound at pack speed, makes it shed oxide and backing, so you have to clean the machine once again before you attempt playback. Today's tape also shedded some sort of white, cakey powder. I have no idea what it was but every crumb had to go.

Next you align the path from tape deck to console to DAW with tone from the tape. Then you punch in and roll the tape.

http://www.in2guitar.com/images4/apr5003.jpg
This tape was properly stored tails-out. Yesterday's was heads-out. You get to watch genuine VU meters dance as the tape plays. When finished, you carefully secure the end of the tape with splicing tape to maintain the pack.

And of course, as soon as the tape is finished it is time to clean the machine. And the cycle goes on.

Bob

RRuskin 06-13-2018 09:33 AM

"white cakey powder" = mold.

Bob Womack 06-13-2018 10:11 AM

Quote:

Originally Posted by RRuskin (Post 5755910)
"white cakey powder" = mold.

Thanks. And here I thought they had been held in a reasonably climate-controlled environment.


Bob

srick 06-13-2018 11:02 AM

Bob - you are bringing back fun memories. In college, I was very active in our radio station. Plus I had a first class commercial license, so I was often in the guts of the machines.

Ah... Along with that lovely "chunk" from the solenoids, there was the the smell of burnt resistors, blown capacitors and the total disaster when the overnight dj spilled his Coke into the console:)! This was college after all!

srick 06-13-2018 11:03 AM

I have never heard of baking the tape - what is that achieving?

KevWind 06-13-2018 11:18 AM

Quote:

Originally Posted by RRuskin (Post 5755910)
"white cakey powder" = mold.

Well if it is from the 70's it could be refined cocoa leaves, left over from a wild recording session :D

Bob Womack 06-13-2018 12:15 PM

Quote:

Originally Posted by srick (Post 5755995)
I have never heard of baking the tape - what is that achieving?

Tape is hygroscopic - it absorbs the moisture in the air around it over time. There was a period, roughly 1977-2000, when the tape formulations became worse about this. We didn't know it until years later. The part of the tape that absorbs moisture is the binder or adhesive that holds the oxide and back-coating to the backing. Once it has absorbed moisture two things happen: oxide and back-coating shed and the binder becomes gooey. They both shed onto the tape heads and guides and become a sticky, abrasive mess. This is called "Sticky Shed Syndrome."

Through 3M research we've learned that the best basic, first step treatment to salvage a tape is to bake it at about 120'F for two hours. This removes the humidity, restoring the adhesive property of the binder. Once you bake the tape you have about thirty days to transfer the tape before it reverts to its previous state, as long as you keep it in a cool, dry environment. There are also other treatments that can be done, but you have to send the tape to a specialist to get that treatment. I sent the 2" multitrack masters for a film soundtrack that I recently archived and mastered to CD to Sonicraft in NJ and they did a wonderful job.

Tape needs the exact opposite of guitars. It does pretty well being stored at 40% humidity at 65'F.

http://www.in2guitar.com/myhistory/tapedeck2sm.jpg

Bob

DupleMeter 06-13-2018 09:07 PM

Aah analog...the sights, sounds & smells...

...and that feeling you get in the pit of your stomach when you realize you left all the tracks armed for that quick punch in :(

Bob Womack 06-14-2018 05:55 AM

I forgot to mention that the interviewee on this show was Rear Admiral Jeremiah Denton. He was a Naval aviator who was shot down over Vietnam and made a POW at the Hanoi Hilton. When forced to participate in a televised propaganda broadcast he blinked the letters "T-O-R-T-U-R-E" in Morse code with his eyelids to let the government know what was going on in the POW camps.



Bob

jstroop 06-14-2018 08:11 AM

Aaahh, you’re taking me back to my radio production days. One word: Ampex.

Bob Womack 06-14-2018 09:22 AM

Quote:

Originally Posted by jstroop (Post 5756772)
Aaahh, you’re taking me back to my radio production days. One word: Ampex.

Yep. Before we were a Sony house we were all Ampex. Our 2-tracks were ATR-102s and the multitracks were MM1200s.

http://www.in2guitar.com/images/pps3atrssm2.jpg

My room had three of the ATR-102s. We sold thirteen of ATRs to ATR services after we went over to the Sony machines. They are now rebuilt and all over the world as the most desirable tape transports in the world.

I asked Michael Spitz at ATR to send me one of the cueing handles for old time sake and he sent me this lovely hand-turned early version:
http://www.in2guitar.com/images/atr100knob.jpg


Back in my college days I worked on A352 and A440C decks. Manly stuff! They'd tear off your fingers if you didn't know what you were doing. HERE are a few fun stories from analog days.



Bob

jstroop 06-14-2018 05:53 PM

Lovin’ this walk through the shadows of my memory. Producing for a radio station was the most fun (and almost the worst-paying) job ever.

jstroop 06-14-2018 05:56 PM

Interesting factoid previously unknown to me ...

“Ampex's first great success was a line of reel-to-reel tape recorders developed from the German wartime Magnetophon system at the behest of Bing Crosby.”

(From Wikipedia)

Bob Womack 06-14-2018 06:49 PM

Quote:

Originally Posted by jstroop (Post 5757318)
Interesting factoid previously unknown to me ...
“Ampex's first great success was a line of reel-to-reel tape recorders developed from the German wartime Magnetophon system at the behest of Bing Crosby.” (From Wikipedia)

After the war, Bing sent a team into Germany to "obtain" the German's technology because he wanted to be able to time-shift his shows with the best sounding recordings possible. The Germans had added to magnetic tape recording an AC bias signal that reduced distortion and smoothed low-frequency response. He then paid to have the technology replicated and developed into the modern recording technology we use via the company he was an officer of, Ampex Corp. In 1955, an engineer at Ampex named Ross Snyder came up with the idea of converting individual track heads on the record head to playback in order to allow overdubbing of multi-channel tracks without taking the previous recording down a generation. He called it "Sel-Sync." Les Paul took delivery of the first multitrack with Sel-Sync and developed the techniques for its use, and my job (recording engineer) was created.

I basically owe my job to three people.

Bob

jstroop 06-14-2018 07:32 PM

Quote:

Originally Posted by Bob Womack (Post 5757374)
After the war, Bing sent a team into Germany to "obtain" the German's technology because he wanted to be able to time-shift his shows with the best sounding recordings possible. The Germans had added to magnetic tape recording an AC bias signal that reduced distortion and smoothed low-frequency response. He then paid to have the technology replicated and developed into the modern recording technology we use via the company he was an officer of, Ampex Corp. In 1955, an engineer at Ampex named Ross Snyder came up with the idea of converting individual track heads on the record head to playback in order to allow overdubbing of multi-channel tracks without taking the previous recording down a generation. He called it "Sel-Sync." Les Paul took delivery of the first multitrack with Sel-Sync and developed the techniques for its use, and my job (recording engineer) was created.

I basically owe my job to three people.

Bob

Bob, do you realize what nerds we are?


All times are GMT -6. The time now is 03:58 PM.

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=