Best auto-reverse R2R for pre-recorded 4-track tapes ?

[goldear]

I would look for one of the closed loop Drive Technics, RS-1700, I believe. If the heads and rollers are in good shape, you may be just amazed at its performance.. They used to outperform A-77 all the time and gave a HS B-77 a real run for the money. The wow and flutter is extremely low, tape tension is no problem and frequency response and signal to noise are more than adequate. I think the Revox has better LF linearity because of the head design and its much easier to calibrate and work on. But the Technics doesn't have the brake issues A-77 or B-77 can have.

I agree the Omega loop Technics machines have excellent transports. And the build quality is excellent. I can't remember if the 1700 features auto-reverse or not though. But there is a single regard in which I dislike the Technics machines though: I find that they subjectively sound slightly "sterile" to my ears. I don't have that issue with the Sonys (nor Revoxes nor Tandbergs, from among the world of consumer machines). YMMV.

 

[Wilhem]

The Technics RS-1700 could play and record in forward or reverse. It uses a photo-optic sensor to read through clear base film or leader to sense the end of the tape to reverse in the record or playback mode at then end of the tape on "side A" or to reverse again only in the playback mode at the end of "side B" for continuous playback.

 

[KentTeffeteller]

The RS 1700 will also set you back a small fortune for a nice example. There are no parts either, the Sonys with roto-bilateral heads weren't that good. Keep your A 77 or get a B 77 in nice condition, and get up and change reels manually. The ReVox will keep running with care when X 2000 machines become parts decks or landfill. The ReVox brakes are not the problem, the problem with them is their users/abusers. If you feather the brakes meaning rewind/fast forward/then stop or opposite, the brakes are fine. I have had A and B 77 machines in home and professional use with proper operation who's brakes never needed replacement. I'd much rather work on a ReVox A or B 77 or a PR 99 than repair any Akai machine or any X series Teac. Read thy user manual, follow it's advice.