A Bluetooth stereo is a type of audio system that uses Bluetooth technology to wirelessly stream music from a compatible device, such as a smartphone or tablet. It typically consists of two or more speakers that are paired together via Bluetooth to create a stereo sound experience. For B50 Stereo amplifier, you can use it to power your bookshelf speaker or passive speaker to build advanced Bluetooth stereo system. B50 support ACPWorkbench tuning tool which allows you to tune different audio on each channel. So you can enjoy you customizable Bluetooth stereo with B50 Bluetooth stereo amplifier.