The point at which the device comes closest to being cut off is not close to zero signal, so the problem of crossover distortion associated with class-AB and -B designs is avoided.
If you just want to amplify tones generated by the Arduino, try the attached schematic. It will deliver about 0.3W into 8 ohms. If you need more volume than that provides and you want to run the amplifier from 5V, then I suggest this chip http://www.ti.com/lit/ds/symlink/lm4871.pdf or someting similar.[EDIT: corrected transistor types]
I onow this is an old thread, sorry to bother you, but i was wondering: shouldn't there be a resistor between the arduino and the transistors here? And one between the 5v and the cap? I ask because i'm having troubles in my project . The speaker is causing short outs.
I don't understand why you would want to add a resistor between 5V and the cap.
Quote from: dc42 on Jan 28, 2014, 01:03 am I don't understand why you would want to add a resistor between 5V and the cap.Because it'll create a short between +5 and ground? Even though the speaker is just 8ohm, too much current will flow, it basically fried my 328.
it basically fried my 328.