Hi, Nigel and all,
I converted two A77s to high-speed by slotting the motor shafts and
using machine screws and nuts to secure the motors. The first time I
did it, I carefully calculated the required offset and had a
machinist at my job mill the holes precisely for me. The second time,
I copied what had happened the first time very carefully with a round file.
While I prefer other methods of doing this type of transfer, this is
a possible route.
I have two options at present to do slow-speed transfers:
(1) for up to 12.5" reels in a variety of track formats, I use my
Sony APR-5000s and run them at 3.75 in/s and -50% varispeed. I have
an MRL 1.88 in/s cal tape that I use to set the 3.75 in/s
preset 3 to be as flat as I can get. I use 88.2 ks/s transfers for
15/16 in/s tapes and then play them back at 44.1. (or 96/48, depending).
(2) Use the Racal Store 4DS for speeds down to 15/16 in/s, but then
have to convert the constant flux "EQ" to NAB in the computer. These
have quarter-track heads built in and only take up to about 8.5" reels.
At 06:30 PM 2010-05-08, [log in to unmask] wrote:
>Unfortunately, you cannot simply swap the capstan shaft to change
>the speed pair. The capstan motor housing is drilled differently
>for each speed pair to achieve the correct position for the capstan
>centre, pinch-roller pressure, correct tape-wrap, etc.
>A few electronic components also need changing but that's minor
>compared with "moving the holes" in the capstan motor housing.
>All the Best
>From: Association for Recorded Sound Discussion List
>[[log in to unmask]] On Behalf Of Shai Drori [[log in to unmask]]
>Sent: 09 May 2010 04:49
>To: [log in to unmask]
>Subject: Re: [ARSCLIST] Seeking Revox B77 or C274 Slow-Speed Tape Machine...
>Don't know if this is helpful but I have a box full of capstan shafts
>for Studer revox. I'm sure one of them at least is the right speed or 1
>7/8 -3 3/4. Let me know
Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.