most simplest transistor amplifier?

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thanks it works great although I can't seem to make it sound clean
Because without proper bias, the transistor cannot cleanly reproduce the sine wave at its output.
"Bias" in electronics basically means "DC operating parameters, in the idle state." What needs to be done is to bias the transistor so that it can pass the complete positive and negative portions of the input waveform, ie we want it operating in the linear region of the transistor, not into saturation or cutoff. See what you can find out about "Q-point" (quiescent point) and "dc load line" for transistors.
 
i think i can describe it better than i could draw a diagram so here goes..
the positive input wire goes to the base or pin 1 (lets lable the transistors leads pin 1 2 and 3)
and there is a resistor between pins 1 and 2
pin 2 goes to the positive wire of the power supply
the negative wire of the power supply goes to the positive speaker wire
and the negative wire of the speaker wire goes to the negative of the input. and the negative of the input goes to pin 3 of the transistor.
and there is a capacitor between the positive of the input and pin 1 of the transistor.

a little complicated but it works perfectly fine at only 6 volts four double A batteries.
trust me it won't work with any more or any less or it does weird things
(super heats the transistor or massive distortion if i take away one battery or add one more battery)
it works fine except for the amount of DC flowing to the speaker constantly wasting a bit of power

you must change the resistor to very high ohms in order to handle 12 volts and you must have a VERY BIG powerful transistor in order to handle the big amounts of heat! and a really big heatsink is also necessary!
but if your just using double a batteries it should be just fine
list of parts?
1: one transistor (try finding a darlington transistor they amplify much better)
2: one resistor
3: one capacitor
 
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