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simple yet somewhat powerful Amplifier? Answered

I need a diagram or something for an amplifier that could be used as a guitar amp but mainly to play an ipod or mp3 devise. It would need a bass, treble, and main control. It would need to handle a 4-16 ohm load. and on a budget of $30 or less. Any help or referral is greatly appreciated.


The thing that will blow your budget will be the power supply. How do you intend to power the amp, and at what voltage?  Do you have an old power supply available (would need output specs: volts, ac or dc, amps)?

While an amp could be done for that price or lower, there are questions that need to asked and answered first.
1.) Do you want the IPod/MP3 player input to be Monophonic or Stereophonic (mono or stereo)?
2.) Approximately how much power were you realistically thinking of?
3.) Do you want both the auxiliary input and the guitar input to play through the same physical amp or another separate amp?

There are other questions that might apply, but these are design considerations anyone would need to know before any recommendations can be made.


Thank You for replying!

i was thinking of using a normal wall outlet and im sure i could find a cheap transformer from my local thrift shop.

it really dose not matter if its mono or stereo

Im hopeing it could be loud enough to power a large to medium size room... I have 8 speakers im putting in a old time radio (the big 4.5 foot tall ones), i have 2 sub-woofers, 4 mid-ranges, and 2 tweeters. Im able to wire it to a 7 ohm resistance.

I am hopeing it could play through the same amp.

again thanks

I've been looking over different ways to do this within your budget constraints. If you can find a 12V, 2A (minimum) supply or even an old computer PSU you can use (lots of 'ibles on how to do that), you would probably be better off buying a class D or class T amp. You can find 15-20 watt units at PartsExpress, MCMElectronics, EBAY, this answer has a link to one, as does this 'ible. These will get you more power than you can build for the price and they can use common 12V supplies.

You then need to have a preamp and tone control with mixing capability. Try Red Free Circuit Designs and look around. The "MP3" player should have some isolation resistors on the positive connections (tip and ring of the headphone out), probably somewhere in the 100 ohm to 330 ohm range. That prevents signal backfeed at the mixing point. The guitar could use some sort of preamplification. You can do either a single preamp or a stereo preamp. Your call on that one. Only difference is where the stereo isolation is performed. Of course, if you are wiring for mono operation, that point is moot. Then feed the appropriately combined outputs to the tone control and from there into the amp. Hook up your speakers and rock out.

Let me know if you need any clarification on anything.


Thanks again,, you explained everything great, and i have no further questions
.. thanks again i appreciate it

Have a look at the project listed on the right hand side of the page.