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6KM8 amp

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6KM8 [triple plate tetrode] amp

6KM8!!!

For some time I wanted to make something with this tube.
It's a triple-plate sharp cutoff tetrode (+ diode but who cares), datasheet suggests "complex-wave generation".

http://www.tubebooks.org/tubedata/hb-3/receiving_tubes_part_2/6KM8.PDF

I have never seen any circuit with this tube so I have no idea how it should work. Pictures? Someone?

I wanted to start with an oscillator, but now I think I'd make a guitar SE amp to see how it works first. The idea is to have the source signal split into two or three (with different voices/colors) and then get the three channels back together before the power stage.

Something like input -> 6KM8 -three parallel 6C4's or 6AB4's -> 6AQ5.

The choice of the other tubes is just what I have lying around and not your typical 13AX8 whatever.

I've found that the guitar amps I like usually have parallel preamp channels that make it sound wider. Less distortion, more fatness. So I hope with 6KM8 splitting the signal into three it should give it certain tone complexity.

Anybody has something to say?
I would really love to see some circuits with 6KM8 - if there are any documents.
 
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6km8_sockel.png


anyone?
 
Sounds like a simple enough project to breadboard, give it a try. You could use a 6ML8 triple plate triode with one common cathode to mix the 3 signals back in. About the only place you'll see a 6KM8 used is electronic organs. It caught my interest a few years ago and I did finally find a schematic. Now where did it end up...
 
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