• 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.

Most powerful SE DIY design?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi from a toob noob.

Just idly wondering what sort of maximum usable power is available from documented DIY designs for single ended tube amps?

I'm maybe interested in constructing one, and it may as well have some "grunt".

*I'd also like to add the constraint that the transformer and tubes must be reasonably readily obtainable!

What can you suggest?

Thanks

Doug
 
George got >200 watts - The 833A SE Amp Prototype

I would suggest efficient speakers with a few watts... much easier, safer and cheaper.

Yeah well ... "custom transformers" are definitely NOT on my parts list.

Let's all have cold shower and venture back to the land of something-that-may-not-blow-up-and-take-out-your-eye.

Anything slightly less hair-raising out there?

Doug
 
Hi!

When this should be easy to build and not use kilovolt B+ supplies, you will be pretty much stuck in the single digit Watt range.

Best regards

Thomas

Yes that's right, although there is one possibility that springs to mind.

The 13E1 is a large regulator beam tetrode - Pa +pg2 = 100W. Its gm is 35. I built a p-p amplifier with these which was successful = 33w at 1% THD with only 275V HT. Now run 13E1 at 400V and 200mA and I would expect to see 20W.

Paul
 
There is power for power sake and then there are some simple SE designs that sound good.

I have a Tubelab SimpleSE cranking out about 7W running just shy of 500V and using the big honkin Edcor CXSE @ 5K impedance. At 3K it would put out more power (maybe 10W)but have higher distortion. I have some James OPT's with multiple impedance options and I tried 3K and 5K, I much prefer the 5K.

Input tube is a 12AT7 variant and power tubes are EH KT90s's a cousin to the KT88 and I am running each tube around 90mA (pretty hot).

This little amp really cranks and I prefer it to a 300b SE amp I built although I never got to fully debug it when one of the 300b's broke.

With good iron and "premium" coupling caps (I dare not say boutique) I am using Jantzen silver Z's which were like $20 each - you will build a very "high end" sounding amp. IMO decent $10-$30 film or PIO caps would be appropriate here.

Many builds are highly documented here and for such a simple little amp it is a good first tube build and the boards are very high quality although a few people have done this amp P2P wiring.
 
Last edited:
"it may as well have some "grunt""

In general, the concept behind the SE triode paradigm is to have a low wattage amplifier coupled to a highly efficient speaker. Let the speaker do the work! It is truly a change in perspective and one can accept the premise or not. Most DIYers will look at the speaker/amplifier as a unit that works in synergy.
 
There is power for power sake and then there are some simple SE designs that sound good.

I have a Tubelab SimpleSE cranking out about 7W running just shy of 500V and using the big honkin Edcor CXSE @ 5K impedance. At 3K it would put out more power (maybe 10W)but have higher distortion. I have some James OPT's with multiple impedance options and I tried 3K and 5K, I much prefer the 5K.

Input tube is a 12AT7 variant and power tubes are EH KT90s's a cousin to the KT88 and I am running each tube around 90mA (pretty hot).

This little amp really cranks and I prefer it to a 300b SE amp I built although I never got to fully debug it when one of the 300b's broke.

With good iron and "premium" coupling caps (I dare not say boutique) I am using Jantzen silver Z's which were like $20 each - you will build a very "high end" sounding amp. IMO decent $10-$30 film or PIO caps would be appropriate here.

Many builds are highly documented here and for such a simple little amp it is a good first tube build and the boards are very high quality although a few people have done this amp P2P wiring.

I built the same amp, currently running EL34s in triode mode, so maybe 5 wpc. I built the amp with UL mode capability for more power, but I never use it because I don't need it.

Like others have pointed out, you want to pair a SET amp with sensitive speakers that don't need more than a few watts.
 
George got >200 watts - The 833A SE Amp Prototype

I would suggest efficient speakers with a few watts... much easier, safer and cheaper.
A chinese 211,845 or 805 SET is inexpensive and viable in everyday use,
the 833A use a 10 Ampere filament, it will explode the electric bill:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
 
A chinese 211,845 or 805 SET is inexpensive and viable in everyday use,
the 833A use a 10 Ampere filament, it will explode the electric bill:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Yes but I do not thi.k that 1kV HT supplies are suitable for a beginner
Paul
 
Last edited:
Hi from a toob noob.

Just idly wondering what sort of maximum usable power is available
from documented DIY designs for single ended tube amps?

I'm maybe interested in constructing one, and it may as well have some "grunt".

*I'd also like to add the constraint that the transformer and tubes must be reasonably readily obtainable!

What can you suggest?

Thanks

Doug

Hi,

It simply doesn't work like that, SE and grunt don't go together.
"may as well" being unrealistic, "readily available" is unrealistic.

Two tubes in push pull will do about 4 times as much power with
the same iron as a SE amplifier, you don't build SE's for grunt.

rgds, sreten.
 
Why do you need so much power? If you want to build an SE amp there are several very good, well documented designs on this forum...my favorite is the KT88SE, do a quick search and check that one out...lots of people have built it and it is a very simple design...i think it is good for about 10 or so watts depending on your choice of running the tube pentode, UL, or triode....
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.