6V6GT scematic, any good, comments?

[ak_47_boy]

http://www.bonavolta.ch/hobby/en/audio/6v6_3.htm

Does this scematic look good? What is your guess on wattage? I would like this amp as the hf in a triamp setup. I like electric guitar solos

I have a bit of confusion, this amp is quad 6V6 mono? The two other 6V6's are added in paralel?

Any info on this would be appreciated

thanks

[SY]

The original article is worth reading. It was reprinted in one of the Audio Anthology volumes from AudioXpress. Basically, like all CF output stages, you trade off problems by forcing the driver stage to swing very large voltages. Yes, it's a mono amp with push-pull parallel 6V6.

55 years later, I'd probably look elsewhere for a circuit to build.

[ak_47_boy]

There arn't an abundance of 6v6 scematics on the net that are around 15watts.

Is there any other tube that would fit the bill?

Now that i think about it "creamy" (6v6) would not be ideal for electric guitar or hf for that matter. I reckon that i need somthing sharper?

Also could you explain to me cathode followers? Link would be good

[Miles Prower]

Originally posted by ak_47_boy
http://www.bonavolta.ch/hobby/en/audio/6v6_3.htm

Does this scematic look good? What is your guess on wattage? I would like this amp as the hf in a triamp setup. I like electric guitar solos

I have a bit of confusion, this amp is quad 6V6 mono? The two other 6V6's are added in paralel?

Any info on this would be appreciated

thanks

There are a few of things I don't particularly like about it. If you need that much Po, I'd rather either get a couple of big RF power triodes, or perhaps triode a big RF pentode like the 813. Getting eight 6V6's all pulling together either requires very careful matching, or a PIC based bias circuit. I have my doubts as to how paralleling like that actually works.

Secondly, using RC coupling and fixed bias is just asking for trouble. Overdrive the grids, and you end up turning on the cathode/control grid parasitic diode which adds grid bias (how Class C amps derive most, if not all, of their operating bias) and forces the finals into more non-linear operation until that excess charge leaks off. Add gNFB as is done here, and the results can be really nasty.

Lastly, using cathode follower outputs does reduce the amp's Zo for better speaker damping, but requires that much more input drive voltage. I'm not sure the results are any better than turning the 6V6s around, and using local NFB to reduce the effective r(p). Might give better results since that wouldn't put such a big demand on the immediate driver stage so far as output swing is concerned.

[Audio_idiot]

hi,
Any specific reason why you are looking at 6V6?

EL84 can get you there too, they are a whole library of circuit available if you google, all parts can be obtain easily too.

another good choices would be EL34.

Cheers

Merry X'mas

[ak_47_boy]

Tubes and their sweet spots.

I thought i had somewhat of a conclusion but i take 1 step forward and 2 back. I am stuck in triamping hell

Anyway i need around 20watts for high frequency. I mostly listen to classic rock and i like guitar solo's both acoustic and electric (no distortion)

I was trying to keep my whole system triode, tetrode, or pentode but i think that will be hard and or pointless.

[Geek]

Hi,

Originally posted by Audio_idiot
Any specific reason why you are looking at 6V6?

EL84 can get you there too....

Same tube, different bottle. 6V6 is just sexier

[ak_47_boy]

6V6 is a tetrode and el84 is a pentode right?

[Geek]

Originally posted by ak_47_boy
6V6 is a tetrode and el84 is a pentode right?

From my book:

6V6 Beam Power Pentode

6V6 has beam plates, EL84 doesn't.

Did some simple PP amp research a couple of weeks back on 6V6 vs. EL84 - they are swappable (mind the brands, I like running them at 350V that many new ones can't take).