Tutorial: – The Adafruit 20W Stereo Audio Amplifier – MAX9744 @ The Adafruit Learning System.
Pump up the volume with this 20W stereo amplifier! This slim little board has a class D amplifier onboard that can drive 2 channels of 4-8 ohm impedance speakers at 20W each. Power it with 5-12VDC using the onboard DC power jack and plug stereo line level into the 3.5mm stereo headphone jack and jam out with ease. Since it’s class D, its completely cool-running, no heat sinks are required and it’s extremely efficient – up to 93% efficiency makes it great for portable or battery powered rigs.
We like the MAX9744 amplifier at the heart of this board because its very easy to use, but it also has both analog and digital volume control capability. Use a single 1KΩ pot (we include one) to adjust volume analog-style. Or hook it up to your favorite microcontroller and send I2C commands to set 64-steps of volume amplification.