got a lot of 12 6GM5 to sell and trying to think of ways to promote its use.
- know it can be used push pull :
Hi quality Push Pull Amplifier with PL500 / PL504/ EL500 / EL504 / 6GB5 /6P41S /27GW6 and 12AU7 /ECC82 and 12AX7 / ECC83 | TUBES.RS – Tube Amplifiers & NOS Tubes
https://i.imgur.com/A7uB7fS.jpg
https://i.imgur.com/eHTgtr9.jpg
- - how it might fare in SE or PP triode amplifier use? or perhaps regulator pass element?
- know it can be used push pull :
Hi quality Push Pull Amplifier with PL500 / PL504/ EL500 / EL504 / 6GB5 /6P41S /27GW6 and 12AU7 /ECC82 and 12AX7 / ECC83 | TUBES.RS – Tube Amplifiers & NOS Tubes
https://i.imgur.com/A7uB7fS.jpg
https://i.imgur.com/eHTgtr9.jpg
- - how it might fare in SE or PP triode amplifier use? or perhaps regulator pass element?
6GM5 is a 7591 in a bottle with 9-pin mini B9A base.
6GM5 characteristics are identical to those of 7591 and 7591A.
I'm sure if you do a search for 7591 in triode you'll find more info.
A friend of mine and I built a push-pull class A 7591-triode amp, years ago, using fancy Tango transformers. It sounded OK, but I think 7591 is better used ultralinear, not triode. But that's just my limited experience.
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6GM5 characteristics are identical to those of 7591 and 7591A.
I'm sure if you do a search for 7591 in triode you'll find more info.
A friend of mine and I built a push-pull class A 7591-triode amp, years ago, using fancy Tango transformers. It sounded OK, but I think 7591 is better used ultralinear, not triode. But that's just my limited experience.
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"rongon" is correct. The 6GM5, 7868, and 7591 are electrically equivalent.
A socket change in a 7868 unit would make very good use of those tubes.
A socket change in a 7868 unit would make very good use of those tubes.
quite cool - - look what I found on the EL500/6P36S as single ended triode
6P36S IN TRIODE MODE
6P36S / 6П36С beam tetrode in triode mode – Bartola(R) Valves
6P36S SINGLE ENDED AMPLIFIER
Tube power amplifier
6P36S IN TRIODE MODE
6P36S / 6П36С beam tetrode in triode mode – Bartola(R) Valves
6P36S SINGLE ENDED AMPLIFIER
Tube power amplifier
The 6GB5 is a small TV sweep tube. The maximum screen grid voltage spec is 200 volts. My experiments with the 13GB5 said to stay at 250 volts or less in triode. There you will get 2 or 3 watts in SE. Running them in push pull pentode with up to 500 volts on the plates is a different story, there you can get 80 watts or more. I saw over 100 before the red glow of death appeared.
Hello,
First trial tonight .
I couldn't help but replace my dummy loads with my little Kef speakers. The sound is a little weak but you shouldn't expect anything powerful. the voltage values are almost the same as those I obtained with PSUD 2 (B+=268v instead of 265v).
First trial tonight .
I couldn't help but replace my dummy loads with my little Kef speakers. The sound is a little weak but you shouldn't expect anything powerful. the voltage values are almost the same as those I obtained with PSUD 2 (B+=268v instead of 265v).
No hum but a little trouble:
Why i can ear some weak hissing sound though my speakers ?
Is it due to the tubes (tetrode and pentode triode strapped)?
There are 100R screen grid resistor on each tube....
Regards
Why i can ear some weak hissing sound though my speakers ?
Is it due to the tubes (tetrode and pentode triode strapped)?
There are 100R screen grid resistor on each tube....
Regards
Thanks for reply
1k for output tube but 150R at input tube.
I will increase the value to 1k.
Tube socket mounts are homemade.
1k for output tube but 150R at input tube.
I will increase the value to 1k.
Tube socket mounts are homemade.
The miller effect capacitance of a pentode is lower than the miller effect capacitance of a triode.
Your 6J52P pentode that is triode wired has more miller effect capacitance than when it is in pentode mode.
However, even with the 6J52P in triode wired mode (with the screen grid signal swing moving the same as the plate signal swing) . . .
A 1k stopper resistor will not affect the high frequency response at 20kHz.
Your 6J52P pentode that is triode wired has more miller effect capacitance than when it is in pentode mode.
However, even with the 6J52P in triode wired mode (with the screen grid signal swing moving the same as the plate signal swing) . . .
A 1k stopper resistor will not affect the high frequency response at 20kHz.
Hello,
There is a little better.
But hissing sounds are still here.
I will increase the 6j52p screen resistor value to 150ohm.
A if it isn't enough i will do it with 6p36s.
I must have a look with my scope too.
Regards
There is a little better.
But hissing sounds are still here.
I will increase the 6j52p screen resistor value to 150ohm.
A if it isn't enough i will do it with 6p36s.
I must have a look with my scope too.
Regards
Am curious about who makes, and what type of audio output transformers that you have there.
Chinese transformers.
But they look not so bad.
4 c core iron : 23H 320R 5,3K
Perhaps i must weld a little capacitor on them (few pf).
But it's possible that the trouble comes from the whole wiring.(No chassis for the moment)
But they look not so bad.
4 c core iron : 23H 320R 5,3K
Perhaps i must weld a little capacitor on them (few pf).
But it's possible that the trouble comes from the whole wiring.(No chassis for the moment)
Attachments
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