me making things: Audio modules

3W + 3W USB Power Supply Mini Digital Audio Amplifier Board:

DIY audio for your MP3, MP4, Laptop or any application which USB power can support. This one is built using the PAM8403 "Filterless 3W Class-D Stereo Audio Amplifier".

Power Supply: DC 3.6~5.5V.Do not use a power which higher than 5.5V.
Output power: 3W + 3W, SNR: 90dB, Efficiency: >90%

Got this from DealExtreme.

LM393 Sound Detection Sensor Module Sound Sensor:

When there is sound, outputs low level and the signal light
Working voltage:DC 3.3-5V
Main chip: LM393, Electret condenser microphone

Note: This sensor only recognizes the availability of sound (vibration principle) can not identify the size of the sound or the specific frequencies of sound.

Got from this sellers ebay listing.

Analog Sound Sensor Board Microphone:

With Power LED, Sensor Indicator LED
Pin1 AO (Sensor Analog Output)
Pin2 GND (Ground)
Pin3 VCC (3V~24V)
Pin4 DO (Digital Output)

Got from this sellers ebay listing.