How might a 6GM5 do tied as triode?

[Ixnay]

Something tells me that you have done this before. You're hired!

 

[Marco audio]

I never builded a single ended amp.

 

[Ixnay]

Your attention to certain details stands out, even at this stage of deciding where to place what. I will look forward to seeing the end result.

 

[jhstewart9]

How might a 6GM5 do tied as triode​

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Should work, move ahead & try it. Get back to us with some results & let us know.

J stewart, a guy who spent 45 years in hitech sales.

 

[Marco audio]

Hello,

Now i'm in doubt about the 0v of my negativ bias power supply wiring.
It was wired on the blue electrolytic caps ,and now it's wired at the input caps (PIO grey).
Hum is still here.
I think i must join this black wire at the nearest of cathodes tube to short the path of current,isn't it ? (Between the both yelow bias circuit caps on picture)

Regards

 

[Marco audio]

after few readings , i must try to elevate the filament voltage... to be contined.

 

[Marco audio]

Bias and heaters are grounded otherwise.
Hum disappear.
But still hissing sounds.

 

[Marco audio]

Ripple voltage measurement:
psud2 give 0,2v.
I have less.
Not so bad with a 5h choke coil.
So i think power supply is ok.
Hum is coming from a bad weld or/and a bad grounding.

 

[Marco audio]

Well, i build it and it sounds good !

No hum and hissing sounds have disappeared.
They came from the 6j52p.
Astonished what it is possible to do with 12w at the anode.

 

[Marco audio]

PS: 6j52p are strapped as follow :
G2 and G3 to the anode with a 220R resistor on each.Speakers are silent without input signal.
G3 to ground give hissing sound , even with a resistor.
I noticed too that some 6j52p are microphonic.
Regards