Home audio systems are getting smaller and more perfect all the time. Nifty soundbars playback music and movie soundtracks with extraordinary clarity and power; compact home theatre speakers provide a surround-sound experience that is thrillingly immersive; and AV receivers deliver high-resolution that sends shivers of pleasure across your eardrums. But the biggest thing happening in home audio is smart home devices from Bose and Sonos that work with Amazon Alexa. Alexa uses speech recognition to “play some Pink Floyd” or “turn up the volume”. It can even adjust the lighting, so your music appreciation comes with the correct mood.