Can anyone identify this amp?
 

It's a valve amp with 2 large output transformers, 4 x ECL86, the neon in top right was added later.

Re: Can anyone identify this amp?
 

Stereo 20 would appear to be a Leak model, perhaps supplied as either kit or open chassis for installation into the user's own cabinet as all I can find online are bare chassis. This is only a guess though & the valve complement does not match what I have found for the 1958 Leak, this being: 4 x EL84, 3 x ECC83, 1 x GZ34.

Re: Can anyone identify this amp?
 

Pretty sure that it`s nothing to do with Leak - They had separate pre and main amps and the shape is all wrong, nor as far as I know, did they ever use ECL86s.

Re: Can anyone identify this amp?
 

I have to agree it's unlikely, any idea why it would be badged as Stereo 20 (perhaps someone attempted to "piggyback" on Mr. Leak's good name?)

Re: Can anyone identify this amp?
 

"stereo" and "20" are pretty common names with amplifiers of that age - it looks like a low volume manufacturer , design probably based on a Mullard circuit - could even be a kit.

Re: Can anyone identify this amp?
 

Picture too poor to be sure but this has similarities.

Cheers

Mike T

Re: Can anyone identify this amp?
 

I have one of these although it's not in working condition. They were sold by a long defunct company called RSC Hi-Fi Centres Ltd which advertised in PW & PE in the sixties. The Stereo 20 was available in kit form or as a ready built chassis. The ready built version sold for 14 guineas in 1967. RSC's mail order operation was in Leeds but there were some retail outlets mainly in the North.

Alan

PS Post crossed with Mike's.

Re: Can anyone identify this amp?
 

Some photos here:

********************gallery/K9mQY

Yes, I think I remember RSC having a presence in a fading Newcastle shopping arcade in the late '70s.

Paul

Re: Can anyone identify this amp?
 

a bit more info
it also has 2x zaeux 12ax7 / ecc83
and some more pics

Re: Can anyone identify this amp?
 

I'm pretty sure that those aren't the original output transformers. The mains transformer has also been moved from its original chassis location.

Alan

Re: Can anyone identify this amp?
 

yes going on mike t rsc advert it appears to be different op tranys also the mains transformer has been removed and a separate power supply has been added to the left side looking from the rear and to the right is a magnetic and ceramic preamp

we also had a rsc in Sheffield closed early 70s
a shame cause it was a good shop

Re: Can anyone identify this amp?
 

Lots and lots of ready built or kit amps in PW [that would be very welcome now] back in the mid sixties. Relatively cheap but generally out of reach for many of us teenagers :(. We used to plug in guitars to valve radio PU sockets-sometimes with a separate speaker for more volume or to protect the one in the set8-o

Dave

Re: Can anyone identify this amp?
 

They look like generous sized output transformers for 10W or so. Looks like someone who had some idea of what they were doing has had a go at an RSC amp. It should give a good account of itself when up and running. Pity about the ECL86s, they're getting rather expensive to replace if they're tired compared with EL84s and separate triodes.

Re: Can anyone identify this amp?
 

I am sure they are not, they look very much like Leak transformers, it will be interesting to see them from below.

Brassbits, are they black or dark charcoal grey?

Alan

Re: Can anyone identify this amp?
 

They are black and appear newish no makers name or markings, with ohm output selector on top of each one

Re: Can anyone identify this amp?
 

It is highly unlikely they will have anything to do with Leak. They look similar to the type as used in the well regarded "Tripletone Stereo 8-8" which has the same valve line up.
The specification on the OP's amp is good (and with a high sensitivity) just think what it would cost to buy a new amplifier of this specification today!

Re: Can anyone identify this amp?
 

When first aquired many moons ago I started reverse engineering the RSC Stereo 20's schematic but suspect that the relevant piece of paper has now disappeared into the ether. I too wondered whether it was based on a Mullard design although the closest I've found so far dates from 1962 and is reproduced here on The National Valve Museum's website:

http://www.r-type.org/articles/art-003f.htm

The pre-amp stage is quite different of course as it uses a single triode EF86 rather than the RSC's ECC83. Otherwise the push-pull configuration of the ECL86s is quite similar.

Sadly the mains transformer in mine has shorted turns due to overheating. Anyone have a spare they don't want?!

Alan

Re: Can anyone identify this amp?
 

ajgriff
Alan does your amp have the 9 pin chassis mounted plug as on mine on the top at the side of the cap

Re: Can anyone identify this amp?
 

With reference to post #17, I notice the advert pictured in post #6 does indeed attribute the design basis to Mullard.

Re: Can anyone identify this amp?
 

So it does. Probably where I got the idea as I have a 1967 version of the advert.

Alan