I am building a paper speaker that is driven by digital output from the Arduino, but the audio is very quiet. Speaker is quite small at the moment, but will be about 4ft in diameter eventually.
What I want to do is amplify the signal so that I can increase the volume. When connected to an amp, the speaker is loud enough, but since I am creating the sound simply by rapidly switching a digital pin on and off (rather than inputting audio), I don't want to use the amp.
Can I make a very simple circuit to make the speaker louder? I've been researching this for the last couple of days (assuming that I could use a transistor ) but am quite confused, and don't want to mess about too much without understanding the circuit, since I'm worried about damaging the Arduino.
Any help really appreciated, or at least a pointer in the right direction.
Maplins recommended this transistor, which I bought from them. But I don't entirely understand all the info on the datasheet, so am dubious about using this (Also looks like it requires 11 V input?? Or is this up to 11V?):