This has probably been asked a billion times, but here goes:
I'd love to build a tube power amp for guitar with a single EL34. I'm just a regular bedroom guitarist with neighbors, so a dual 100W Marshall mono block seems a bit excessive(although they make me drool). Thus came the idea of a single EL34 amp, preferably as simple as possible. With a risk of stating the obvious: I don't want any pre-amp distortion, no tone stack, no tube buffered gold plated spring reverb etc. Just El34 overdrive.
You'll have to forgive me, I know nothing about tube amp design. I'm aware of the AX84 designs and the like, but they seem to be pre+power amp designs. I already have a pre-amps, so the AX84 designs are too complicated. I don't know, if I could just cut out the parts I don't want, like the tone stack? I guess not though?
There's also this guy:
New build - single ended EL34 with power scaling (10w) | My Les Paul Forum
which seems to be exactly what I'm after. The link to the schematic is down though... Bummer. He uses a VVR to get more drive at lower volumes, which seems like a cool feature.
So what it all comes down to is that I'm looking for a schematic for a purely power-amp with a single EL34. As simple as possible
Thanks!
I'd love to build a tube power amp for guitar with a single EL34. I'm just a regular bedroom guitarist with neighbors, so a dual 100W Marshall mono block seems a bit excessive(although they make me drool). Thus came the idea of a single EL34 amp, preferably as simple as possible. With a risk of stating the obvious: I don't want any pre-amp distortion, no tone stack, no tube buffered gold plated spring reverb etc. Just El34 overdrive.
You'll have to forgive me, I know nothing about tube amp design. I'm aware of the AX84 designs and the like, but they seem to be pre+power amp designs. I already have a pre-amps, so the AX84 designs are too complicated. I don't know, if I could just cut out the parts I don't want, like the tone stack? I guess not though?
There's also this guy:
New build - single ended EL34 with power scaling (10w) | My Les Paul Forum
which seems to be exactly what I'm after. The link to the schematic is down though... Bummer. He uses a VVR to get more drive at lower volumes, which seems like a cool feature.
So what it all comes down to is that I'm looking for a schematic for a purely power-amp with a single EL34. As simple as possible
Thanks!
How much experience do you have building amps ? Have you built any pedals or did you build the preamps yourself.
I ask because used to think how hard could it be? If you are looking for simple, star with pedals a such as those by run off groove like the fetzer.
Maybe you can make your own chassis have other electronics experience?
Schematic is only the 10% inspiration the rest is the perspiration
Sent from my iPhone using Tapatalk
I ask because used to think how hard could it be? If you are looking for simple, star with pedals a such as those by run off groove like the fetzer.
Maybe you can make your own chassis have other electronics experience?
Schematic is only the 10% inspiration the rest is the perspiration
Sent from my iPhone using Tapatalk
Agree and add: as simple as you want it to be, no preamp on Earth will drive the EL34 straight, so you need at least one triode stage driving it.
In practical terms it means you will need an EL34 *and* a 12AX7.
You may use 1 triode to drive the power tube and leave the other disconnected, ... or you might build a Fender Champ, just with an EL34 instead of a 6V6 and call it a day.
You can add a jack so you feed your preamp straight to the volume pot , but if some day, for any reason, you do not have your preamp available, you can plug your guitar in the original Champ input and wail away.
There is nothing simpler than a Champ.
of course, build a more modern power supply, with SS rectifier diodes instead.
In practical terms it means you will need an EL34 *and* a 12AX7.
An externally hosted image should be here but it was not working when we last tested it.
You may use 1 triode to drive the power tube and leave the other disconnected, ... or you might build a Fender Champ, just with an EL34 instead of a 6V6 and call it a day.
You can add a jack so you feed your preamp straight to the volume pot , but if some day, for any reason, you do not have your preamp available, you can plug your guitar in the original Champ input and wail away.
There is nothing simpler than a Champ.
of course, build a more modern power supply, with SS rectifier diodes instead.
There's two really simple SE EL34 designs on Bonavolts pages
Michel Leluaux from "L'Audiophile" (April 92). Power 6Wb
Rainer zur Linde from his book "Build your own Audio Valve Amplifiers".
There's also new SE EL34 design that's available: The Solo using inexpensive components and with a fair degree of community support (if this is your first build). Dumping the tone stack is dead easy.
At 10W it might still be too much for bedroom use in which case something like a PP 12AU7 amp (1W) might be a better option. There's a few of them around such as the Lunchbox. If you just want an amp, drop everything to the left of the volume pot, earth the tremelo point T and dump the tremolo oscillator.
ps. re-read what Glaznost45 wrote: it's not clear what your motivations are,. So you might be better served by a RunOffGroove project backed up by a 5W class D chip amp. Especially if it is your first project.
Michel Leluaux from "L'Audiophile" (April 92). Power 6Wb
Rainer zur Linde from his book "Build your own Audio Valve Amplifiers".
There's also new SE EL34 design that's available: The Solo using inexpensive components and with a fair degree of community support (if this is your first build). Dumping the tone stack is dead easy.
At 10W it might still be too much for bedroom use in which case something like a PP 12AU7 amp (1W) might be a better option. There's a few of them around such as the Lunchbox. If you just want an amp, drop everything to the left of the volume pot, earth the tremelo point T and dump the tremolo oscillator.
ps. re-read what Glaznost45 wrote: it's not clear what your motivations are,. So you might be better served by a RunOffGroove project backed up by a 5W class D chip amp. Especially if it is your first project.
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I think the OP was quite clear
Not sure how a triode based amp (as in *any* triode) or a FET simulation can get even close
Notice that he already discarded real tubes as EL84
; so I didn´t even suggest he uses an octal power tube (6V6) which would be real close to EL34 but he straight uses "the real thing".Guitar players are very fussy about what they use.
A full-power SE EL34 is a VERY LOUD bedroom amp.
Even a Champ (one 6V6, half the watts of a full-out EL34) will annoy the house and neighbors.
> I already have a pre-amps
Many different things are called "preamp".
A guitar amp usually needs one "preamp" stage to boost signal to near 1V, and another "driver" stage to boost that to the near 20V that the power tube need to be hit with. Both preamp and driver add flavor.
When you get into very small "power" tubes you *may* be able to skip one stage. The last of the 1W 110V radio/phono finals could be driven with less then 3V, so a hot preamp could smack them. 6AU6 can do likewise at 1/3rd Watt. They should make fine bedroom g-amps. I do not know of any pre-tested plans to compete with a raging EL34. And "saving one stage" is a minor point since we love the 12AX7 twin-triode.
Even a Champ (one 6V6, half the watts of a full-out EL34) will annoy the house and neighbors.
> I already have a pre-amps
Many different things are called "preamp".
A guitar amp usually needs one "preamp" stage to boost signal to near 1V, and another "driver" stage to boost that to the near 20V that the power tube need to be hit with. Both preamp and driver add flavor.
When you get into very small "power" tubes you *may* be able to skip one stage. The last of the 1W 110V radio/phono finals could be driven with less then 3V, so a hot preamp could smack them. 6AU6 can do likewise at 1/3rd Watt. They should make fine bedroom g-amps. I do not know of any pre-tested plans to compete with a raging EL34. And "saving one stage" is a minor point since we love the 12AX7 twin-triode.
I second the Solo as a first-project. It has enough flexibility and power to be used for years and years with a high level of satisfaction. No, you might not need two gain stages before the power tube to get good clean acoustic tones. Yes, the TMB stack and other sound-shaping componentry can be omitted (or modified) quite easily. However, the (low) extra initial investment makes the rig a lot less of a "hobby" class device, that can stand up and shout alongside some very expensive relatives. It is a simple enough design to be able to assemble correctly in one session, without having to troubleshoot anything. If something does go wrong, there's not a whole lot to troubleshoot. If you don't like the look of the extra knobs, nobody said you can't hide them somewhere off of the faceplate.
There are a gaggle of "micro-lunchbox-bedroom" amp heads (and even more combos) available on the market that cannot match the strength and poise of this basic design. The coolest thing about it (besides the DIY factor) IMHO is that it lends itself to rolling tubes through it. If something is lacking somewhere, just try another flavor of 12AX7 in it. Let your ears be the judge as to what sounds right or wrong.
There are a gaggle of "micro-lunchbox-bedroom" amp heads (and even more combos) available on the market that cannot match the strength and poise of this basic design. The coolest thing about it (besides the DIY factor) IMHO is that it lends itself to rolling tubes through it. If something is lacking somewhere, just try another flavor of 12AX7 in it. Let your ears be the judge as to what sounds right or wrong.
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Somewhat along similar lines, check out the P1 eXtreme SE project amp on AX84.com. It's a very popular DIY build, fully documented with schematics, etc, and fully supported by the AX84 community. It's designed to be able to take a whole variety of overall power tubes, starting with EL34s. Now here's the the thing, the P1eX let's you control exactly how much preamp or power amp overdrive you want, by means of its gain and volume controls.
Sent from my phone. Please excuse any typpos.
Sent from my phone. Please excuse any typpos.
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Nice amp, I´d only add a bridge rectifier instead of the lonely half wave 1N4007 shown.
PT will love it, hum will be lowered and higher frequency (easier to filter out), what´s not to like ?
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