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Leak Stereo 20

Discussion in 'classic' started by Tony L, Jan 31, 2012.

  1. kevinrt

    kevinrt pfm Member

    Are the black (-ve) speaker terminals a ‘signal ground’ on the Leak Stereo 20?

    It’s with reference to connecting a wire from a subwoofer to ‘signal ground’. The manual warns that the black speaker outputs are not signal ground on all amplifiers.


  2. Tony L

    Tony L Administrator

    The Leak inputs and outputs, like much vintage kit, have continuity back to mains earth.

    PS Always worth having a multimeter for this sort of thing, makes life so much easier.
    kevinrt likes this.
  3. Alex S

    Alex S carbon based lifeform

    After a few more days I can say the Marshall/EI long plates really are great in my Leak/system. I’ll see how long they last.
  4. foxwelljsly

    foxwelljsly Me too, I ate one sour too.

    I’m dropping my father’s stereo 20 off to Mike for a service in a week or so, but am clueless about valves.

    I think this thing is stuffed with 20 year old sovteks, during which time, the amp has been used a lot. If they’re still working, is it worth replacing or upgrading them?

    My pockets do not extend to NOS Mullards, but might stretch to something cheaper.
  5. Tony L

    Tony L Administrator

    The small ones should be fine, hopefully the rectifier too, though the EL84s are likely end-of-life. If you know someone with a valve tester I’d test them all. The results aren’t conclusive of an imminent fail but can give an indication as to where they are in their life. Obviously any noise or imbalance are good clues too. My advice is always to have multiple valve sets so you can easily contrast and compare against a known good/new valve.
  6. chiily

    chiily PFM Special Builder

    I bought four of these EL84-SOVTEK (Sovtek) from Watford Valves and three Sovtek 12AX7LPS Long Plate from

    They sound pretty good to me.

    I do have three EI ECC83s on the way though. :)

    Edit: I forgot that I've bought a quad of Soviet (CCP marked) 6P14P Reflector A-GE valves. I've not tried them yet; another good buy from Ukraine.
    Last edited: Dec 1, 2022
    Mike P, foxwelljsly and myles like this.
  7. chiily

    chiily PFM Special Builder

    Interestingly, I tried the 6P14Ps last night. The sound was quite a bit sharper, if that makes sense, certainly added quite a bit to stage depth.

    More listening over the weekend to come.
  8. Mike P

    Mike P Trade: Pickwell Audio

    Yeah, they are a bit crisper aren't they.
  9. myles

    myles Intentionally left blank

    Could you provide a link please?
  10. chiily

    chiily PFM Special Builder

    I'm wondering if they are too crisp for the Fortes. Hmmmmm...

    I did have a moan in the "what ya listening to now" thread about the terrible hack someone has had with remastering Scary Monsters and Super Creeps, it was so flat. Reverted to the FLAC I have of the CD and boy was the sound crisp...and then I remembered the album and that has guitar that sounds like it would cut you open...gawd it sounded great, so maybe the Fortes are more balanced than I thought.
  11. chiily

    chiily PFM Special Builder

    foxwelljsly and myles like this.
  12. Amormusic

    Amormusic pfm Member

    I feel like I've owned my one of these long enough now to form a full opinion upon it... My amp now has many-many-many hours of playing in my living room, each of them filled with a smile.

    It really is a very special amp, and does an astounding job of just removing the kit from the room. No longer are there speakers, wires, etc. etc. there is just the musician/band etc. performing to me in my room. Instruments are like actual instruments, voices have texture and definition, and it just sounds so... um... right.

    I've heard a lot of amps. Mostly they're good, and some can excel in one way or another. This amp excels in that it is a musical-machine, a bringer of joy, a wild grin to your face. It's hard to write it down.

    In a word. Special.

    For 60 year old tech and kit. This absolutely spanks so many things I've heard. We're not even in the same country of the same ballpark.

    I took it to a bakeoff and someone commented "when it's right, it's right" - so true - all the years and supposed advancements of tech... Pah... Stick the Leak on it will blow em away :)
    Alex S, Fizzy, Pkay and 2 others like this.
  13. Amormusic

    Amormusic pfm Member

    I love it. Can you tell :)
  14. foxwelljsly

    foxwelljsly Me too, I ate one sour too.

    Cheers, just bought a bunch of el84s and ecc83s from this chap to get us going after I pick up the freshly restored Stereo 20 from Mike.
    Darmok likes this.
  15. chiily

    chiily PFM Special Builder

    Cool, enjoy the Leak they are quite special and certainly not pipe and slippers.
    Mike P, Fizzy, Amormusic and 2 others like this.
  16. Fizzy

    Fizzy New Member

    I'm glad there are a few like minded souls here. I've owned my Stereo 20 for nearly 30 years. It was well restored before I got it and has only required minor fettling and new valves since despite regular use. Currently running Tung Sol valves and sounding as fabulous as ever through ESL 57s.
    Quad74, chiily, Amormusic and 2 others like this.
  17. Mike P

    Mike P Trade: Pickwell Audio

    What ECC83 valves did you buy?
  18. foxwelljsly

    foxwelljsly Me too, I ate one sour too.

    Voskhod military valves. I have a saved search to find a better one for the primary one. Be interesting to hear these when I collect the amp. The el84s I've ordered are reflectors.
  19. Mike P

    Mike P Trade: Pickwell Audio

    6N2P? They are NOT a direct drop in equivalent. Don't try and use them in your ST20!
    foxwelljsly likes this.
  20. Darmok

    Darmok "In Lation, Trans Lost."

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