• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

1650NA+4x6L6's in triode=?

I am leaning toward a tube amp project over the next few months and am just rolling around ideas.
I am looking for 20W MIN with triode connected output tubes.
Idea 1:

Hammond 1650NA 4300ohm primary
4 x 6L6GC per channel connected in triode, fixed bias
B+ will be about 460VDC


What would be my power output? Is 30W about right?
Leaning toward a LTP phase inverter. perhaps based on the Conrad Johnson MV75 using either a 6CG7, 6SN7, 12BH7 similar med mu dual triode
Or perhaps a Williamson type circuit -my first big project over 25 years ago was rebuilding a pair of Heath W5's


If I could come up with an 8K output I could use a pair of 6550's for about 20W maybe
I am open to ideas.
 
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At first, it would be to make the 6L6 loadlines on the graphic. Perhaps the traffo is OH, but most possibility is that no. So be sure to find the best load impedance. After it, choose the traffo.

I suggest respectfully to learn a bit of electronics. Make an amplifier isn't to merge circuits unconsciously. The blender doesn't help you here. You need to balance impedances, voltage gains, frequency charts, phase rotations, etc.

Be sure that 460V is a potentially dangerous voltage to play without good common sense.-
 
My first big tube amp used 1650N transformers and 4 6P3S per channel. You will probably get 25W out of it, maybe a little more. They are pretty nice transformers. Also check out the 1650NA with the "easy wire secondary"...


yes I meant the 1650NA
Did you use the 6P3S coin base ones?

I think those were closer to 6550's than 6L6's. Lotsa tractor parts in there.

I think the Golden Tube SE40 got 40W from 3 in PSE IIRC?
 
At first, it would be to make the 6L6 loadlines on the graphic. Perhaps the traffo is OH, but most possibility is that no. So be sure to find the best load impedance. After it, choose the traffo.

I suggest respectfully to learn a bit of electronics. Make an amplifier isn't to merge circuits unconsciously. The blender doesn't help you here. You need to balance impedances, voltage gains, frequency charts, phase rotations, etc.

Be sure that 460V is a potentially dangerous voltage to play without good common sense.-


I don't have any common sense. But I have built over 1000 tube amps (guitar). I know how to avoid getting a few ma through the heart.

So do you have any specific criticism of a LTP under consideration that is broadly similar to the CJ MV75? I would use a slightly simpler AC balance circuit.
 

kodabmx

Member
Paid Member
2011-10-31 1:00 am
Toronto
yes I meant the 1650NA
Did you use the 6P3S coin base ones?

I think those were closer to 6550's than 6L6's. Lotsa tractor parts in there.

I think the Golden Tube SE40 got 40W from 3 in PSE IIRC?

No... I liked the spec and price for the non -E version. It's a like a metal 6L6 in a glass envelope and they were cheap. They don't red plate until about 25W but I now use sweep tubes connected as triodes for my amplifiers. :)