Denon Home 150 Wireless Speaker, HiFi speaker, WiFi, AirPlay 2, Google Assistant/Siri/Alexa Compatible, HEOS Built-in for Multiroom - Black with 250 Stereo speaker with 350 bluetooth speaker : Amazon.co.uk: Electronics & Photo
The Ultimate Guide to Wireless Speakers
Wireless speaker tech explained: Wi-Fi and Bluetooth differences | Stuff