For those who like electronic stuff or just audio in general here is some small woofer porn
5WRMS amp doin work... - YouTube
This is a guitar amp I am designing for my friend...I am using 4 6v cells for good capacity and making it portable...otherwise I would have designed a wall power supply. I am surprised on what 5wrms will do to the 3 different speakers I have tested with. The speaker in the vid is an A8 ohm so I it recieves a little less then 5w but it gets to movin! After messing with the design I can get the output to 15wrms...
The amp is a class B design which isn't heard of much in the audio world. It has great sq, no crossover distortion like class B's have unless you apply negative feedback and biasing diodes like I have on this one. It uses an opamp for the pre-amp and small to-92 transistors in a darlington configuration connected to larger power output transistors with heatsinks.
In the vid it is JUST on the verge of clipping...I didn't measure it on this track so there may be a tad clipping but really it sounds clean off camera and I have a cheap camera so don't take the audio recording as it apears there is no significant distortion at all.
The surprising thing is that the woofer is rated at 75-100w rms IIRC...So for only 5 watts it is a pretty efficient woofer. It can be used full range.