Wireless amplifiers allow you to send a strengthened audio signal to a hifi speaker system with no cables involved. They are highly suitable for outdoor systems involving in-wall or in-ceiling speakers where it is difficult to run long wires. While they are designed for hifi speakers, they are not recommended for applications requiring extremely high quality audio, such as a professional home cinema. Most streaming amplifier models are compatible with most speakers and media players, connecting via bluetooth or a wifi network. The Yamaha MusicCast system allows you to connect multiple inputs and outputs, and control them easily form a mobile app.