Mini Subwoofer 25mm (Smallest Subwoofer in the World) by Mark Anthony T. Montero - YouTube
Best battery powered subwoofers - Portability is now an option.
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Funktion-One Launches Its Smallest Loudspeakers To Date At ISE 2020 - ProSoundWeb
This Is the World's Tiniest Subwoofer - Wide Open Roads
Rel Acoustics T-Zero: the best small subwoofer to boost your compact speakers? - Son-Vidéo.com: blog
New Lanzar MAXP84 Max Pro 8'' 800 Watt Small Enclosure 4 Ohm Subwoofer 744271348743 | eBay