In short the question is: how can I get the audio from the 3.5mm port of my Raspberry Pi board to play through a small external speaker? Space is a concern in this project I will only have a few square inches and it only needs to be loud enough to be audible within ~20 feet.
More details: I'm working on a Raspberry Pi project where I want to have it play some sounds. The board itself will not be hooked up to a monitor or anything at run time so the audio will need to come through the 3.5mm jack. I raided an old clock radio to steal the speaker out of it and stripped one side of an old set of headphones so that I could connect the wires to the speaker I pulled. The sounds are playing fine through the intact earbud but when I connect the bare wires to the speaker I don't hear anything.
What can I do to get this working? Do I need some sort of amplifier? Are there better options than what I'm trying? I was hoping that the small speaker would just run off of the power coming through the headset wires.