• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Kondo M77

(...) but those SS diodes might also be part of a hybrid Graetz bridge rectifier. What should a SS diode bypass be good for?
Glad that you opened this subject.
Aside from the 77 preamp,I encountered the same thing (SS diodes wired in parallel with the tube rectifier - in this case,a 6X5) on the Kegon.The SS diodes pictured here are By448.I was told that the SS diodes are there for preventing the sag (inherent for a tube rectifier) but the sound character stays "tubey" :confused:
 

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With due respect, this is utter nonsense. The SS diodes' low impedance completely shortcuts any influence of the rectifier tube.

Anyway and out of experience, there surely aren't too few audiophools who strictly believe in the 'tubey' rectifier sound of their device, 'cause the rectifier tube is present and they see it glow.

Best regards!
 
the Chinese were the first to do that afaik many many years ago a push pull kt88 class A with a single 5u4, i knew then that something is probably not right, so someone posted the sockets and low and behold silicon rectifiers........you pull out the rectifier tube in the middle of play and the thing still played music.... :D
 
With due respect, this is utter nonsense. The SS diodes' low impedance completely shortcuts any influence of the rectifier tube.

Anyway and out of experience, there surely aren't too few audiophools who strictly believe in the 'tubey' rectifier sound of their device, 'cause the rectifier tube is present and they see it glow.

Best regards!

it is, but today, they can get away with anything...myself do those too....silly me.. :D

but hey, diy allows you to be crazy and do crazy stuff, just do nto get killed in the process is the only limitation....

Merry Christmas......
 
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Glad that you opened this subject.
Aside from the 77 preamp,I encountered the same thing (SS diodes wired in parallel with the tube rectifier - in this case,a 6X5) on the Kegon.The SS diodes pictured here are By448.I was told that the SS diodes are there for preventing the sag (inherent for a tube rectifier) but the sound character stays "tubey" :confused:

if that is a tube amp, it is tubey, ss rects or not...:cool:
 
Le Basseur: Please share any additional photographs of KSL equipment which you may have which may inspire our DIY efforts - thank you.
Tony: please do not continue to clutter this thread away from the OP intent of learning more about the design at hand.
Apparently you are a moderator, as such you should know better - consider yourself as reported.

JP
 
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Just another Moderator
Joined 2003
Paid Member
:cop: a) Tony is a retired moderator. b) any comment from a moderator that is not acompanied by a :cop: emoji is a moderator posting as a normal member.

c) Mod hat off, I don't find Tony's post at all antagonistic. He simply related his opinion on a technical matter. You reacted (since deleted) and he said if you like it then that's fine. Everyone has their own preferences, and Tony has simply acknowledged that in my opinion.
 
Thanks Tony, and Merry Christmas to you and the rest of the gang.......

exciting times indeed.....out of the norm tube circuit practices, nothing surprises me anymore, i think i have seen it all, but no...occasionally someone comes up with surprises, all the more exiting.... :D
 
What is moderator emeritus - ?
Thanks for your comments, end of the day - they are just that.
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Le Basseur: Please share any additional photographs of KSL equipment which you may have which may inspire our DIY efforts - thank you.
To the mods: dont rob the hand which feeds you.
-
Perhaps you could do well with a new moderator.
I can help with that.
 
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Thanks Tony and all the best to you and yours for the festive period.
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This is not 'my scheme', this is the KSL M77 schematic, which is why I ask that you stand-down from further comment - please.
On principle I'd put CCS everywhere, and it should sound better, right?. Yep, and when it doesnt, what do you do?.
Dont blame me - just TRY it. So easy, yet so hard - maybe diyaudio should focus more on 'do' - oh wait, it does 'D' in the 'IY'.
Get busy before you get back ..

JP
 
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but i do not see anything outstanding with the m77....design wise....

yes, even KSL's have their roots from somewhere....but the thing to learn here is the how and the why's of such scheme...

Broskie has treated this subject very well imho...it is a shame for anyone to miss it.....

you may also want to look at valve wizard, merlinb aka Merlin Blencowe is such a fine author and has written in a way that is easy to understand...

lastly, if you get a copy of Morgan Jones' tube books, then those will fill you up very nicely with tube wisdom....