Speaker Materials that Sound Good

Some quick insights into building speaker cabinets with pleasing acoustic performance. April 17, 2009

Question
Is there any way to determine if a certain wood would be good to use as speaker cabinets?

Forum Responses
(Furniture Making Forum)
From contributor G:
The inner box of a speaker cabinet is typically 3/4" MDF, and the outer box maybe MDF again (or ply) with a nice wood veneer. Walnut is a good choice for the veneer, and trim out with solid. It’s typically finished with oil or low sheen coats. Additional material is added to inside of box the help dampen sound waves. Cone midranges are typically shielded, boxed off somehow when sharing the same air with the woofer. All the things inside help ensure pure sound, while the outside wooden beauty (and expert fit and design) reflects itself as a fine musical instrument.

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From contributor T:
Being an ex-pro sound guy, professional speakers cabinets (such as studio monitors, concert hall cabinets, touring cabinets, and etc.) were all made from thick laminated baltic birch ply. Most touring cabinets were two 15mm BB sheets laminated together with a fiberglass and epoxy outershell. Sub-cabinets were often three sheets laminated.

Particle board with a hardwood veneer was typical for smaller rooms and decorative applications. MDF was never a choice as it naturally resonates between 80hz - 140hz. Some folks like that uncontrolled boomy sound.

So basically, what you want is a hard dense cabinet material. How the cabinet is constructed is also important. The driver itself is coupled to the free airspace and shape of the cabinet interior. A "tuned" box has lots of confusing math associated with it (for me at least) so it's best to stick to any plans recommended for the driver you want to buy.

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From contributor R:
I have built a few, and the latest does have some very bad boom-y spots in it (bass sub cabinet). I had attributed it to horrible room acoustics, but now I wonder. Perhaps erroneously, I've always considered MDF as a kind of finer grained particle board. I didn't realize that particle board would be a superior product in some cases. I'd better rethink this, and maybe rebuild that last sub.