tube amp schematic

A single 6AQ5 is not a suitible choice for a guitar amp. Two 6AQ5's in push pull can be used to make a class AB1 amp of about 10 Watts power output. This is quite feeble for a guitar amp. Of course you will need an appropriate output transformer and a power supply giving 250 Volts at 70mA. Furthermore you'll have to get the tubes and parts for the front end and phase splitter, 12AX7 and 12AU7 or something similar.

If you are serious about it, consider two EL34' tubes for the output stage and don't screw around with 6AQ5's. The amount of work is nearly the same and when you are through you'll have a much better amp. Bob

An amp? With _one_ _6AQ5A_?

Might as well plug high-impedance phones right into the guitar jack.

Good Luck! Rich

Here are a few web sites that should get you going.. More info than you can consume in a day, for sure. Knock yerself out!!!

If none of those sites give you what you want, just Google for "guitar amp schematics" and see how many you come up with.

Hello Don,

Can also be done with a CD4007. But then again, a 6AQ5 gloweth so nicely. A DSP lacks that retro feel.

Regards, Joerg

Hello Sampei,

If you can't find much on the web there are still several options:

a. Obtain a really old ARRL Handbook, at least 30 years old. Lots of tube amp schematics in those.

b. Look at the schematics of the Drake TR-4 ham radio transceiver. It used to be very widespread in the 70's and used a 6AQ5 for the receiver audio.

c. I believe the Gibson Skylark tube guitar amps also used it.

d. If you find a large public library somewhere that doesn't throw out older books they might have something, too. Probably only in big cities.

Regards, Joerg

A single 6AQ5 is not a suitible choice for a guitar amp. Two 6AQ5's in push pull can be used to make a class AB1 amp of about 10 Watts power output. This is quite feeble for a guitar amp. Of course you will need an appropriate output transformer and a power supply giving 250 Volts at 70mA. Furthermore you'll have to get the tubes and parts for the front end and phase splitter, 12AX7 and 12AU7 or something similar.

If you are serious about it, consider two EL34' tubes for the output stage and don't screw around with 6AQ5's. The amount of work is nearly the same and when you are through you'll have a much better amp. Bob

Hello Bob,

Or if you are really serious about it, take even bigger tubes. One amp I built had an array of PL519, probably the equivalents to the 6KD6. That amp produces a lot of oomph. One twang on the guitar and the rafters shook.

Regards, Joerg

Maybe just make a preamp. How much plate voltage to get the thing to work? 100V?

You can get transconductance at amazingly low plate voltages. I saw an article in QST or something, 30 or 40 years ago, that had a QRP receiver with 12 V. on the plates. 12AX7, I think.

But was the guy's question, "How do I build a TOOB amp" or "I found this TOOB - how can I use it?"

I say, mount it on a minibox, and drive the filament with a 6V lantern battery in series with the speaker output from a real amp. Set it on top of your stack - It'll look KEWL! %-}

Cheers! Rich

Drinking glasses + red LEDs + DSP

Go to the hardware store and buy an Amprobe.

Cheers! Rich

Near 3W or more, it does...