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What a big vacuum tube! Single Ended Mono Block Power Amplifier

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roog

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I was most interested, or should I say fascinated, about the size. Just wanted to show it.:)

Here is information from the manufacturer:

"Power Output max. 170 Watts @ 1 kHz
Noise 110 dB below rated output "A" weighted"

They didn't write anything about distortion levels.

They write a lot about damping factor. Something of a "super damping factor". I don't know what it is, a good damping factor? About Damping factor they write:

"Damping factor 8 ref. to 8 ohm load @8 ohm tap, 32 ref. to 8 ohm load @4 ohm tap (super damping factor mode), both @ zero global feedback."

Good or not? I do not know. I was most fascinated by the size of that power vaccum tube.Just wanted to show it::)
View attachment 240072


To get an idea of the size check out this video. A picture from the video, the amp on the far left has the 300B power vaccum tube. The amp on the far right is the big Magma New HPS:
View attachment 240074

13:45 into the video:

He talks in this video at some length about dealers of tubes not knowing what they are talking about. I'm not convinced from his contribution to this video that this fella knows much about the application of tubes in SET amplifiers either. He seems to know how to buy/borrow them and talk a lot about very little meaningful.

He uses the terms 'Kick start' and 'Jump start' and mentions the requirement for a 'certain type of listening' not technical terms I have heard of in the SET amplifier world. Just asking because he says, 'Trust me', for some reason I don't.

I can't believe I clicked on his video to watch it now.
 

mhardy6647

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big output triode...

electron-tube-history-radio-television-news-november-1954-6.jpg


RCA UV-862 100 kw. water-cooled triode tube
Plate: 18,500 volts at 5 amps.
Filament: 205 amperes at 32 volts.
now you're talkin' :)
You could make a great SET audio amp with a couple of these -- you'd get that little extra bit of headroom, you know?

source https://worldradiohistory.com/Archive-Radio-News/50s/Radio-News-1954-11.pdf (magazine pp 65-67)

 

groove

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GM100 has a high brightness filament and is very blinding. 18V 20A. I build amplifiers on it with a translucent front panel. Monoblock size 245*600*500mm. SE 100-150W A2.
 

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DanielT

DanielT

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GM100 has a high brightness filament and is very blinding. 18V 20A. I build amplifiers on it with a translucent front panel. Monoblock size 245*600*500mm. SE 100-150W A2.
Impressive! :)
did he ever say what was the "Little guy Mystery Amp" shown at the very end?
Well, I don't know.:)
 

groove

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Impressive! :)
Thanks.
I started with EL34, KT88 got boring. Then 6S33S, GM70, GMI30 and it got boring again.
So I came to the GM100.
In general, I like PP fully balanced tube circuits. Therefore, even this SE GM100 amplifier has a differential input and a balanced output. This is necessary to reduce and control even harmonics.
 

groove

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360W per mono block just on the heaters! Madness.
The filament supply DC. Only a powerful diode bridge 100A 1600V integrated into the radiator coped with this task.
Anode supply 1600-1700V current 250-350mA
 

tomtoo

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100A * 1600V thats if iam not wrong 160kW. I must be wrong, or something else is wrong. Or my worldview is wrong.
 

groove

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Aren't big vacuum tube really just big dick surrogates? ;):)
I don't know about a big dick, but you need to have a serious fortitude if you want to have such an amplifier at home. I am currently producing a couple of monoblocks for a person from Estonia.
 
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