Speaker cabinet materials.

Cabinets are rarely made of wood....MDF is a good damped cheap material.

Contrary to popular belief - good heavy and heavily damped cabinets with bracing add almost no audible effect on the sound - apart from the acoustic suspension from the enclosed volume of air which does affect the driver damping and affects the driver selection.

Common cause of this popular belief - cheap light weight speakers with cabinets that "waffle" and do indeed affect the sound.

Check out Green Mountain Audio. They use cast marble cabinets that are supposedly extremely rigid. Their bookshelf monitors alone weight in around 50 lbs each! There is supposed to be nearly zero box loss contributing to an incredibly clean and coherent sound.

Celestion SL-600 and SL-700 used aerolam.

Check out Green Mountain Audio. They use cast marble cabinets that are supposedly extremely rigid. Their bookshelf monitors alone weight in around 50 lbs each! There is supposed to be nearly zero box loss contributing to an incredibly clean and coherent sound.
Djembeplay (Threads | Answers)

Even marble flexes. One of the first mods GMA made to the Diamante was adding aluminum ribs bonded to the inside of the cabinet to reduce flexing.

Green Mountain enclosures are cast using our proprietary Q-Stone (TM). It has a much different formulation than used in our Diamantes from 1993 to 1997. No internal braces are required. It is far more rigid, and with far greater internal damping. And yes, heavy too, which by itself has little effect on the sound.

Best regards,
Roy Johnson
Designer
Green Mountain Audio