RE: Looping on Revoxes (a treatise)

["Goddard, Duncan" <goddard.duncan@mtvne.com>]

http://www.dgmlive.com/diaries.htm?artist=&show=&member=3&entry=7559

 

it's "just" two tape decks side-by-side.

 

prepare for some spoddiness-

 

the important stuff isn't really mentioned in these eno-instructions, like

how to disable the unused reel motors....

how to synchronise the two capstan motors, or disable one of them, so the tape doesn't go slack or break.....

the exact angle the two machines have to be parked at so that the tape isn't fouling any of the deck.....

how to defeat any tape-motion sensors that might not be moving in this configuration....

how to wire up the remote so that one deck starts in play at the same time as the other starts in record.....

 

THEN- do you use the decks in mono or stereo? do you also use the play head on the record deck to give you a short echo aswell as the eno delay?

do you use an external mixer (more flexible) or the revox's own input mixing (more compact)?

 

the one with the red background looks as if it concerns itself with the level control & mixing side of things, & the one with the yellowish background MAY be to do with which deck starts first & what happens to the free tape between the decks. the writing isn't clear enough to read, but I don't think there's enough of it to cover things like modifying the reel-motor switches so that only the unused spool carrier is disabled (& not both as would usually be the case), or wiring both machines' remore sockets to a single stop/start switch...... what I can see is instruction relating to which audio level control does what in this context....

 

on the red diagram, you can make out where the guitar is supposed to be plugged in, how audio gets from the second deck back to the first, & which meter the user should be watching. you can see that the record controls are not even shown on the right-hand deck, because they are not relevant.

 

the yellow diagram appears to be a more generic (non-A77-specific) version of the same thing, though there is some notation referring to the slack tape between the decks. I wish I could read what our renaissance-man-parfumier had to say by way of warning-

 

"watch out for this going slack or snapping!"

 

would be my guess..... &- 

 

"if it snaps, try swapping the decks over.... then it will go slack instead- somewhat less disastrous!"

 

they are certainly revox A77s in the red diagram, though I've seen a picture of fripp at work with two G36s, an older revox that uses valves (tubes). interestingly, the G36s are shown on their ends, while the decks in these diagrams appear to be normally oriented. 

 

yes, I have done this a few times myself, & with many different sorts of deck. :-) 

 

I have in the past pondered the benefits of fine-tuning the capstan speeds of the decks to avoid the aforementioned slack tape problem, of cross-connecting the capstan servo oscillators to force the decks to run at the same speed (this solves nothing if the diameters of the capstans differ even by a tenth of a thousandth of an inch), of disabling the pinch-roller on the record deck so that the play deck is doing all the pulling, of mounting a new head & modifying the tape path of a single deck to perform this technique.....

 

I've used two uher portables to do this, too- got a picture somewhere......

 

why? when there are so many digital delays & samplers available, why bother?

 

well..... when I first tried this, back in 1979 with an old ferrograph & an EMI L4 portable, it was hit & miss. I managed to get the capstan speeds matched reasonably well, & had the two very-different machines suitably positioned so that the tape flowed properly. what made it worth-while was the quality of the recordings, & the way the folded-back audio varied according to how worn the tape was at any given point. it was more..... tidal.... than any solid-state equivalent I've ever heard. I still keep a number of A77s & can play with this configuration whenever I want, luckily.

 

anyone else got any experience of using the two-deck setup? anyone know what "skysaw" was? I can't make out anything on that picture, & it seems to have been quite important to RF, since he goes to the trouble of crediting BE with it's invention on the sleeve of "exposure".....

 

duncan.