Leak Stereo 20 and a Thank You

[Alex S]

Yes indeed. It did not provide less gain in the sense of less volume so I stick with my 'more drive' EI comment. Nonetheless, I am fully aware that these are sighted A/B dems and the amp needs to cool (and more since I don't want to switch it on and off all the time) and probably fairly meaningless.

I think I can say that more expensive good valves are better than cheaper less good ones. Whether they're worth the money is for each to decide. I can also say that a well restored ST20 is very capable of showing any system change, including the valves inside it.

 

[Tony L]

I’d ask a grown-up about the 5751. As I understand it this isn’t a straight swap-in on a Stereo 20 as it alters the negative feedback loop. GT, Mike, Radford or Snowman Al will be able to explain better than me, but I’d personally stick to a full-gain ECC83 there.

PS You’ll not do “harm” in an explody way, the amp’s distortion figures etc just won’t be the same.

 

[Alex S]

Good to know. Presuming non explodiness, okay to go by ear? Any grown-ups around?

 

[Alex S]

Please forgive my persistent ramblings but I would like to expand on "a well restored ST20 is very capable of showing any system change, including the valves inside it". I've had what I thought (and what others have thought) were pretty decent power amplifiers but the Leak does seem pretty ruthless at showing what's upstream. Any slight change I've made has been almost instantly revealed. For example, I decided the Kohzmo dual mono (with Elma switch) would be better served elsewhere because of my seating position for the second system. So I replaced it with my Khozmo stereo - same resistors but an inferior switch. To my surprise and chagrin it sounded very obviously worse. I need to settle down or this Leak could cost me a lot of money!

And don’t get me started on recording/mastering quality - utterly transparent with those.