BRUTALIST-Lab - Introducing MONOLITH, the first concrete speaker in the world with terrazzo surface. The simple, minimal and ancient monolith design is a traditional pair of passive speakers with 3-inch drivers and
CPA6NDV2 6.5 INCH Loud Speaker - Concrete Audio
Making Concrete Speakers - by SoundBlab - YouTube
Master and Dynamic developed its own concrete for its first speaker | Engadget
Concrete Audio
25 Concrete Speakers that Promise Best Acoustics and Longevity