• 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.

$120 battery powered tube amp on eBay??

Possible to up the power?

Wiring a wall transformer to this amp would be dirt simple... but... how much voltage? Would more input voltage make the amp more useful? (read:powerful)

It looks like it'd be a fun little project to take a cheap low power amp like this and build it into an iPod amp. Replace the faux center transformer cover / battery case with a dock, and paint the whole thing gloss black to match my nano. Not exactly high end audio, but it'd look sweet.

Hell... if this thing could be built into a decent phono preamp it would actually be quite useful.

But really, I get ahead of myself. I'd love to buy it and tinker, but I'm a total Toob Noob... I know enough about electronics not to fry myself, and while adding a wall transformer plug, input selector switch, and an iPod docking station is well within my capabilities, actually modifying the amplifier circuit (or even trouble shooting) is not.

poynton said:

Please post the circuit.

This might be it. Don't remember where I found this schematic but it fits the bill.


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    three volt hifi tube amp.jpg
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2005-03-10 11:57 pm
Cal Weldon said:

Caution!:Vacuum tube in this kit are made in China more than 30 years ago.It is not acceptable to return the tubes because of scratches or something.


Isn't NOS meant to be a selling point ?

Or are they used, hence the straightener included ?

What are the tubes anyway?
I cannot find a reference. (maybe I did not try hard enough!)