Pretend that the weather is warm and it is a nice time to be outdoors chatting with friends. You want some background music, but where will it come from?

When people want portable music, they usually rely on battery-powered audio devices. Of course you can buy a sound system for outdoor use, but those can be quite expensive and, as we shall show, unnecessary. With just a bit of engineering blood (or curiosity) running in your veins, it is not that difficult to build a wireless Bluetooth® stereo audio system that can be controlled with any device that has a Bluetooth connection and a music player.

This application note describes how to build a simple and fairly low-cost wireless Bluetooth stereo audio system for outdoor use. The system has 20WRMS output power. It can be controlled either with a handset that has a Bluetooth connection and a music player, or with an Apple® iPod® model. Three appendices discuss additional layout considerations, the differences between using a Class D and Class AB amplifier in the design, and the cost of the system.