We tested the Sonos Move 2 portable speaker. It requires being part of the Sonos music system, but if you've bought in, this could be the best portable speaker.
Sonos Move 2 Speaker test - DXOMARK
Sonos Move review: Hefty portable speaker brings big Sonos sound to the outdoors - CNET
Sonos Move - Battery-Powered Smart Speaker, Wi-Fi and Bluetooth with Alexa Built-in - Black : Electronics
Sonos Move Portable Wireless Speaker Review
Sonos Move Review
Sonos Move 2 (White) MOVE2US1 B&H Photo Video
Sonos Move 2 speaker review: Welcome to the portable era
Sonos Move 2 (White) Wireless portable speaker with built-in Alexa, Apple AirPlay® 2, and Bluetooth® at Crutchfield
Sonos Move review - SoundGuys
Sonos Move 2 Portable Wireless Speaker (Each)
Sonos's Portable Speakers Compared: Move 2 vs Move vs Roam vs Roam SL
Sonos Move 2 Portable Speaker Promises Better Sound and Battery Life - CNET
SONOS Move 2 wireless loudspeaker
Sonos' new Move 2 redefines the premium portable speaker
Sonos Move 2 review: serious quality sound with twice the battery life, Sonos