Sonos could soon launch a new smaller subwoofer in cylindrical form. The Sonos app makes references to the new product during setup.
Sonos Sub Mini
The Sonos app refers to the 'Sonos Sub Mini', which appears to be the official name, as "a smaller, cylindrical subwoofer", as noted by a user on reddit.
Sonos already sells a subwoofer, Sonos Sub, for $749 (after the recent price hike). We would expect a Sonos Sub Mini to be more affordable and a good match for the company's compact Beam soundbar.
Also read: Sonos Arc, Playbar & other products now support DTS audio
The app notes that a single Sub Mini can be connected to a Sonos system unlike the current subwoofer, which supports a dual setup.
There is no official word from Sonos yet.

The Sonos app references Sub Mini. Photo: S114HED, reddit
- Source: Reddit via The Verge