How to soften harded pinch rollers? (+ worn tape heads)

[RoadrunnerOZ]

You’d need a notch on each counter reel so they all are at the point you want to cease drive - like say 0007 to come to final rest at 0000 (with an override so it doesn’t stop playing at 0007 when you start again!). Each counter reel any number will repeat at 1, 1/10, 1/100, 1/1000 revolutions and so on but if every reel is notched the notches will all line up only at a unique number so a series of micro switches wired in series or a roller bar and one switch could work.
Fun thought!!

 

[C.B. - Boudio]

It are only three reels (but that doesn't matter). The microswitches, indeed in series, and as such connected to the remote control socket, with a swich in parallel to override them. I just have to come up with something to 'drive' the switches without obstructing the movement. The notches are an interesting path.

 

[RoadrunnerOZ]

It depends on whether the remote control is open circuit for stop or closed for stop whether the switches would be in parallel or series and the override in series or parallel with the micro switch bank. You’d need the switches to trip a self latching relay to hold their status. If the remote is a momentary switch it’s different again!
Edit: the friction of a micro switch may cause the counter reels to not return to zero on pressing the reset button.
Maybe a pinhole through each reel with an LED on one side and sensor on the other to trip the stop.

 

[Brian Roth]

The sync system on the 24 track machines was to record SMPTE time code on one track to use as exact tape position location actual to tape, this being fed back when approaching the sync point by slowing the machines and reading actual position off tape via high speed cueing. With 2 track machines you’re relying on the tape counter which can be out a bit but can still work as long as you zero your counters at start.

The Lynx synchronizer had specific cables that connected from the main unit to each controlled machine. In addition, software was tweaked for each specific machine. In the setup screen, you "told" the system what particular machine was at the other end of the factory supplied cable.

In the case of the machines in our system, tape counter tach pulses were fed back from each machine so the Lynx could "count on it's fingers" and make an excellent estimation of tape position during fast wind. Each machine was required to have a servo capstan that the Lynx could tweak to nail the synchronization of the multiple machines as determined by the SMPTE time code recorded on each machine. The analog tape machines produced SMPTE time via an audio signal recorded on a track (IIRC it was called longitudinal time code....LTC) while the Sony BVU video machine produced Vertical Interval Time Code (VITC). Whatever, it all magically worked quite well.

Something that seems totally foreign in year 2024 is the concept of "pre-roll". You had to park the machines 5 or 10 seconds before the point where you wanted to begin working. That gave the Lynx time to "tweak" the tape position/speed of each machine once you began to start. Pre-roll was a parameter in the Lynx setup screen. So, when you used the Lynx as an autolocator, it would intentionally park all machines to the selected "X seconds" preroll position.

One reason we chose the Otari MTR-90 MK III was it's well-known ability to "play nice" with synchronizer lock-ups. And, we had muddied the waters further by adding an early version of ProTools into the synched system! The Lynx handled all the chores quite reliably.

Bri

/EDIT....sorry for a large veer from the original topic of pinch rollers and tape heads.

 

[RoadrunnerOZ]

The Tascam I modified had SMPTE and tach pulse reading controlling servos, acceleration and braking settings programmable for each machine and dropped the decks into cue mode at destination with a very short brake time. It only needed about 1 sec auto preroll as the cue sensing parked with both machines in sync - we looked at the Lynx and tested but someone from Tascam had the Tascam as a demo unit floating around so I modded that, made adapter cables and it worked better than the Lynx in the end. Even with 14” reels IIRC
I remember some early cassette machines (maybe Sony) using metal foil tape end sensors instead of tape pressure sensors.

 

[Brian Roth]

@RoadrunnerOZ ..... I don't recall the Tascam system at the time we were shopping for a SMPTE sync setup. I'm guessing early 1990's....but that was three decades ago! Could the Tascam device integrate video machines and VITC?

All I recall were the Lynx and Adams-Smith products, and the Adams-Smith didn't integrate with ProTools at that time. We had some really specific needs for doing "post sweetening" for video production.

Bri

 

[RoadrunnerOZ]

@RoadrunnerOZ ..... I don't recall the Tascam system at the time we were shopping for a SMPTE sync setup. I'm guessing early 1990's....but that was three decades ago! Could the Tascam device integrate video machines and VITC?

All I recall were the Lynx and Adams-Smith products, and the Adams-Smith didn't integrate with ProTools at that time. We had some really specific needs for doing "post sweetening" for video production.

Bri

The Tascam could sync up to 4 machines including VTRs. It had self learning for braking and acceleration. We bought it in 1992 after we got the Studer machines. I think it was an ES50/ES51 Synchronizer/Controller. As far as I know it’s still in place but only being used on 1 Studer as the second machine got sold. Had built in transport, record and play functions so it became the remote for each or both machines.
Edit: you used the primary tape machine as the master for any digital recording devices and they had to be able to read SMPTE master.

 

[Gold]

I have three Studer A80 2tr. I had them completely gone over. I had a number of original Studer black rubber pinch rollers. I decided I wanted new ones so went with Athan. I used the cleaner he supplied. I had a couple go sticky on me.

The original Studer pinch rollers looked dirty and maybe a little hard. I used naptha and elbow grease. They cleaned up nicely and have worked great for a couple of years now.

 

[Brian Roth]

Man, the years sure have flown past for me....lol! Dates and projects specifics are fading from memory!

How did that Tascam interface with, say, a Sony BVU machine? As I recall, Sony used a variant of RS-422 for the "editor interface".

Bri

 

[RoadrunnerOZ]

Not sure there - we implemented a Sony 32 track digital recorder but I can’t remember the recording format but it did sync to SMPTE - it slaved off the master tape machine or you could use it as master as it generated time code as well.

 

[Gold]

Not sure there - we implemented a Sony 32 track digital recorder but I can’t remember the recording format but it did sync to SMPTE - it slaved off the master tape machine or you could use it as master as it generated time code as well.

Sony multitrack digital was DASH format. It was 24 tracks on 1/2” tape. Later 24 or 48 tracks on 1/2” tape.

Mitsubishi was 32 tracks on 1” tape. I think the format was called ProDigi.

 

[RoadrunnerOZ]

This was a self contained unit with no tape deck transport - about 4RU - it may have been a hard disk recorder - sat on top of the console at the rear

 

[Brian Roth]

This was a self contained unit with no tape deck transport - about 4RU - it may have been a hard disk recorder - sat on top of the console at the rear

So....no pinch roller to become sticky!

 

[RoadrunnerOZ]

Nope ‍

 

[C.B. - Boudio]

Very interesting to hear about the equipment in the last 'serious' days of tape recording!

/EDIT....sorry for a large veer from the original topic of pinch rollers and tape heads.

Doesn't matter to me, I love hearing those examples of what used to be done in practice.

 

[RoadrunnerOZ]

Editing was done on a splicing block - cutting tape at chinagraph marks on the tape at the right spot to not truncate a kick or snare hit. One track I did for an AC/DC tribute album had over 60 edits - cut segments taped together from 4 separate full song takes on the one reel pair (2 Studers A820’s synced together). We went through each take and ticked off on a chart good lines from each verse, chorus etc, scrolled tape and marked, cut and numbered each segment of tape then hung them on dowels all around the control room and stuck them all back together. The track was Jailbreak by Yothu Yindi for Sony BMG on an album called Fusebox - the producer was Kevin “Caveman” Shirley, I was engineer.

 

[Brian Roth]

@RoadrunnerOZ ..... Cool song!

Re. Studer A-820 machines, I found this pic:

https://medias.audiofanzine.com/images/normal/studer-a820-241941.jpg

Barely visible to the right in the pic you can see a Studer A-800 as well.

I know the Studers were pricey. How much $$$ for a pair when they were new? Estimate is fine! <g>

Bri

PS for @C.B. - Boudio here's some fun bunch of tape editing done on a Revox. The song itself begins around 1:30 into the video.

 

[RoadrunnerOZ]

I know the Studers were pricey. How much $$$ for a pair when they were new? Estimate is fine!

I think they were originally around $65K each - we got two barely used for $22K if I recall.

 

[RoadrunnerOZ]

Splicing block 2”:

 

[CalavoBob]

I got a hold of a Studer 827 that had done that. It had been in storage before I got it. The pinch roller had melted into an ooze that pooled over the top deck plate, dripped down into the pinch roller mechanics below the deck plate, and continued dripping through the transport electronics, into the audio card cage and finally into the power supply at the bottom of the deck. It took me about a month to get all the goo cleaned out but it's running fine now with a new Athan pinch roller on it.