looking for schematic with 6em7 as a driver or...

[RockysDad]

I built Gray Kaufmans 6em7 DC coupled amp and really like the sound of it. The only trouble is that the output power is little low (<1W). Does anyone know of a good output tube to use that would mate well with the 6em7? I've never designed a tube amp before but if I have a place to start, ie. output tube, I could try with the help of you guys here on this board. Of course the best option would be to just have a schematic and start building.

What if I just used another 6em7 an hooked up only the power triode in parallel similar to the DC double Darlings? Would this work? Any other ideas to consider?

 

[GaryW]

Funny you should post. A couple weeks back, I reworked the common cathode 6EM7 voltage/driver stage on my 300b PP amp to direct coupled ala Gary Kaufman. Sounds very nice. You could go with a SE:SE with about any output tube you're interested in. If your output tranny is 3K now, 300B, 2A3, 6B4 are all possibilities.

 

[GaryW]

Looks nice too...

 

[Geek]

Fred Nachbaur's MiniBlok (SE) and MiniBlok II (PP) uses the 6/10/13EM7 as an output....I dunno why it can't be adapted to driver service too

http://dogstar.dantimax.dk (look under "Tube Stuff")

 

[korneluk]

Funny you should post. A couple weeks back, I reworked the common cathode 6EM7 voltage/driver stage on my 300b PP amp to direct coupled ala Gary Kaufman. Sounds very nice. You could go with a SE:SE with about any output tube you're interested in. If your output tranny is 3K now, 300B, 2A3, 6B4 are all possibilities.

Gary,
any preferred/recommended brand of 6EM7 or do they all pretty much sound the same driving a 300B?
TIA,

 

[Tubelab_com]

Jose,

Whatever your choice in 6EM7, the first triode has a 2:1 variance in gain from tube to tube even among tubes of the same brand and construction. You must try a few in your circuit and pick two with similar gains or channel balance will be way off.

I used the 6EM7 as a driver in an augmented cathode follower amplifier following a 1955 patent. It worked very well once I found some good tubes.

The schematic is in post #11 of this thread:

http://www.diyaudio.com/forums/tubes-valves/118289-6336-rectifier.html

The discussion of the circuit is here:

http://www.diyaudio.com/forums/tube...wer.html?highlight=augmented+cathode+follower