Soundfield
1K Club - QQ Shooting Star
I was prompted by Sonik Wiz’s posting about the VIDOX units: https://www.quadraphonicquad.com/forums/index.php?threads/vidox-decoder.25998/post-410387
to investigate other super rare (or effectively non-existant) decoders. One that has always intrigued me is the ReVox A274 and in doing a spot of research discovered that our own Quad Linda had posted a photo of it in a thread that I’d missed somehow: https://www.quadraphonicquad.com/forums/index.php?threads/amp-revox-a-724.16160/post-150885
A little bit of back story. The Studer Revox brand was created in Switzerlad by Willi Studer and became famous in the fifties and sixties for its high quality professional reel-reel machines. It later diversified into high end consumer audio. One of its first major complete hifi ranges was the A700 series:
As a teenager I was completely smitten by the rugged industrial chic and the high technology. In particular I desperately wanted the amazing looking A720 Digital FM Tuner – Preamp:
but was orders of magnitude beyond anything I could afford. My love affair carried on though, and I’d later own what many have considered to the one the finest FM tuners ever made, the B760, but that’s another story!
The point is, that in addition to the preamp and the A722 stereo power amp, there was mention of a matching quad decoder / amplifier for the series, the A724. It was covered in several press releases and apparently made an appearance at HiFi shows. I kept an eye out for it but for some reason it never seemed to appear.
The picture that Linda posted is probably of the only one still in existence. It was taken by one of a small number of ReVox enthusiasts given access to the private STUDER ReVoX Museum in Regensdorf as it was being closed in 2009 (as, sadly, the independent ReVox company was wound up). He took several photos of it actually (some showing the A722 stereo power amplifiers from the same series):
and he says that they are of the “ ReVox A724 Quadro Power Amplifier” and “Of this device only 5 pieces were built, but never came to the market”
It would appear with the closure of the museum, all of the vast collection, representing decades of European equipment manufacturing, was then sold off.
I managed to track down the fate of that A274. On a German audio forum I found this posting in 2013 (thanks to Google Translate!)
“I offer here one of the very rare A724! in their possession for more than 25 years and would now like sell to a "real" collector or fan. Maybe it's the last of the 5 pieces that were made, which still exists? The device is visually in good condition. (There is a bit of paint peeling around the port for the Quadro headset. The device was in the ReVox Museum until this was dissolved. Before the exhibition, the device was revised by the expert of the museum. Since then, the A724 was no longer in operation. The device can be picked up in Central Switzerland or by arrangement in Dogern (Southern Germany).
Asking price: the highest bidder, but at least EUR 4'000.00”
Yes, that’s an eye watering €4,000 !! So I was rather surprised to see that subsequently, in 2014, the original poster added the note:
“The A724 is sold!”
Whether it went for the asking price I guess we’ll never know.
The A724 was scheduled for release and the Studer Revox A700 series worldwide brochure (1973/4):
Proudly shows the unit:
After a long search, the only on-line copy I can find of the brochure is very small and low resolution so it’s difficult to make out the specification page:
I’ve enhanced it and managed to read it. Having done so, after all these years, I’m very disappointed! You can see from the photo that having fitted 4x30 W amplifiers there wasn’t much room for any particularly sophisticated decoder. The text reveals that it was a “20-40 blend” RM/SQ decoder. So that’s about as basic as you could get, and as Sony discovered with its early ‘no logic’ decoders, next to useless.
So I guess that’s the reason this thing never made it to market. ReVox had rushed to design this unit and get it to pre-production really early (1973) – but unfortunately this basic type of raw decoder just didn’t work! I’d always assumed that the A274 was some high performance device in line with the rest of the A700 series – the fact that it wasn’t, almost certainly meant ReVox didn’t want to be associated with it. Doubtless having spent a lot of money on it and having burnt their fingers, there was probably no internal appetite to re-enter the field when a few years later decoding advances would have allowed the ReVox engineers to have designed a very high performance unit indeed. C’est la vie.
Just glad I didn’t spend €4000 on it now I learn what was inside it!
to investigate other super rare (or effectively non-existant) decoders. One that has always intrigued me is the ReVox A274 and in doing a spot of research discovered that our own Quad Linda had posted a photo of it in a thread that I’d missed somehow: https://www.quadraphonicquad.com/forums/index.php?threads/amp-revox-a-724.16160/post-150885
A little bit of back story. The Studer Revox brand was created in Switzerlad by Willi Studer and became famous in the fifties and sixties for its high quality professional reel-reel machines. It later diversified into high end consumer audio. One of its first major complete hifi ranges was the A700 series:
As a teenager I was completely smitten by the rugged industrial chic and the high technology. In particular I desperately wanted the amazing looking A720 Digital FM Tuner – Preamp:
but was orders of magnitude beyond anything I could afford. My love affair carried on though, and I’d later own what many have considered to the one the finest FM tuners ever made, the B760, but that’s another story!
The point is, that in addition to the preamp and the A722 stereo power amp, there was mention of a matching quad decoder / amplifier for the series, the A724. It was covered in several press releases and apparently made an appearance at HiFi shows. I kept an eye out for it but for some reason it never seemed to appear.
The picture that Linda posted is probably of the only one still in existence. It was taken by one of a small number of ReVox enthusiasts given access to the private STUDER ReVoX Museum in Regensdorf as it was being closed in 2009 (as, sadly, the independent ReVox company was wound up). He took several photos of it actually (some showing the A722 stereo power amplifiers from the same series):
and he says that they are of the “ ReVox A724 Quadro Power Amplifier” and “Of this device only 5 pieces were built, but never came to the market”
It would appear with the closure of the museum, all of the vast collection, representing decades of European equipment manufacturing, was then sold off.
I managed to track down the fate of that A274. On a German audio forum I found this posting in 2013 (thanks to Google Translate!)
“I offer here one of the very rare A724! in their possession for more than 25 years and would now like sell to a "real" collector or fan. Maybe it's the last of the 5 pieces that were made, which still exists? The device is visually in good condition. (There is a bit of paint peeling around the port for the Quadro headset. The device was in the ReVox Museum until this was dissolved. Before the exhibition, the device was revised by the expert of the museum. Since then, the A724 was no longer in operation. The device can be picked up in Central Switzerland or by arrangement in Dogern (Southern Germany).
Asking price: the highest bidder, but at least EUR 4'000.00”
Yes, that’s an eye watering €4,000 !! So I was rather surprised to see that subsequently, in 2014, the original poster added the note:
“The A724 is sold!”
Whether it went for the asking price I guess we’ll never know.
The A724 was scheduled for release and the Studer Revox A700 series worldwide brochure (1973/4):
Proudly shows the unit:
After a long search, the only on-line copy I can find of the brochure is very small and low resolution so it’s difficult to make out the specification page:
I’ve enhanced it and managed to read it. Having done so, after all these years, I’m very disappointed! You can see from the photo that having fitted 4x30 W amplifiers there wasn’t much room for any particularly sophisticated decoder. The text reveals that it was a “20-40 blend” RM/SQ decoder. So that’s about as basic as you could get, and as Sony discovered with its early ‘no logic’ decoders, next to useless.
So I guess that’s the reason this thing never made it to market. ReVox had rushed to design this unit and get it to pre-production really early (1973) – but unfortunately this basic type of raw decoder just didn’t work! I’d always assumed that the A274 was some high performance device in line with the rest of the A700 series – the fact that it wasn’t, almost certainly meant ReVox didn’t want to be associated with it. Doubtless having spent a lot of money on it and having burnt their fingers, there was probably no internal appetite to re-enter the field when a few years later decoding advances would have allowed the ReVox engineers to have designed a very high performance unit indeed. C’est la vie.
Just glad I didn’t spend €4000 on it now I learn what was inside it!
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