Leak Stereo 20

[Arkless Electronics]

perhaps, whatever just going by what I was told and heard .... had both ...graphite definatley better, . each were restored by the same person , what he don't know about vintage valve amps ain't worth knowing

The only change in transformer specs happened while they were still the bronze colour (from spec. 3921 to 8778 about'63 ish). AFAIK there were no silver ones. There were a few very early ones made in almost the Marantz "champagne gold" but more pinky than Marantz... Most though were the bronze colour and there was a later change to black/graphite which itself had a change to a darker black. Even rarer were the export only matching Varislope pre amp with a gold front panel which was for USA export only.

They do indeed sound very good... there were a few design miscalculations in the original and a few things which with modern hindsight can easily be improved, all can be done in such a way as to be completely set back to standard if needed. With some mods they can really sing! much more modern still in terms of grip and transparency can be achieved such as they will rival any modern valve amp of similar power... and probably beat most Where do they stand in standard form? Better than Quad but short of Radford is the easy answer...

One of the best sounds I've ever heard was from a Stereo 20 I REALLY modded for a customer who became a good friend (now sadly no longer with us).. regulated PSU's for each stage etc.... feeding into rebuilt ESL57's. Truly jaw dropping

[petrat]

Stereo 20s are ace ... lovely, bouncy, musical things, with more than enough detail to satisfy.
Actually, I have yet to hear an EL84 amp that I don't like.

[jandl100]

Stereo 20s are ace ... lovely, bouncy, musical things, with more than enough detail to satisfy.
Actually, I have yet to hear an EL84 amp that I don't like.

Me, too. The EL84 is my favourite power valve, I think.

I don't get on with EL34 amps at all.

I've owned Leak St20 a couple of times. Excellent. Lots of grip and they let the pizzaz through.

[Jonboy]

The only change in transformer specs happened while they were still the bronze colour (from spec. 3921 to 8778 about'63 ish).

This perhaps is when they changed the output transformers to 20% ultra linear from the original 43% making the sound more open and perhaps powerful, so no i don't think that the line Urban myth applies and still say the graphite sound better