sounds

Wood has higher strength and stiffness to weight ratios than plastics do.

I suspect it's naturally better damped (less resonant) too.

Graham

"Plastic" covers a pretty wide range.

I suspect that it's because for the price, wood delivers good acoustic properties for the price. I also suspect that it's because there's a bit of voodoo in high-end acoustic design, and wood appeals to the liquid-nitrogen-dipped-vacuum-tube crowd more than cruddy old plastic does.

I also know of many cheaper speaker enclosures that are made of pressboard, some small but good-sounding speakers that are made of die cast aluminum (re. Bose), and some small but good-sounding speakers with labyrinths that are made of plastic (Bose again).

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Tim Wescott
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Note that you can find many "mini stereos" that have plastic boxes for the speakers. And of course, any boombox uses plastic.

It's not so much the material, as the quality. Cheap wooden speaker boxes will rattle and shake, while strong wood boxes won't. Cheap plastic, and the same problem, strong plastic less likely. Metal can have its own problems, but also done properly make good speakers.

Apart from anything else, wood is an easy material to work. Plastic requires a process that isn't so economically feasible unless you are making a lot, the setup costs is too much.

In the old days, when there was a variety of hobby electronic magazines, speaker construction articles were common. All kinds of material were used. Cardboard boxes, though they were reinforced and sealed up well. Concrete sewer pipes. Ironically, some of those could afford to use out of the ordinary things that supplied a nice strong box, because unlike commercial endeavors, shipping the heavy materials was not an issue, and someone building their own could live with what others might consider "ugly".

The box in itself means nothing. It's there to make sure the sound comes out of the front of the speaker (and any port, if there is one), rather than from all over. You don't want the box to get in the way of the sound (or want the effect to be as limited as possible).

Michael

Actually, real wood is not such a great material for speaker boxes. The preferred material is Medium Density Fiberboard (MDF) which is a wood composite. It is quite dense and "dead", which is ideal because you don't want the box itself to vibrate, only the air inside it. (It just happens to be inexpensive as well... one of the very few instances where cheaper is better!) I suspect if you look carefully, you'll notice that many speakers that look like real wood are really wood *veneer* over MDF.

Plastic is actually not so bad for those tiny little computer or ipod speakers, since they are small enough so that it's easy to get a fairly rigid plastic structure just by shaping it properly. Panels that appear flat on the outside can easily have ribs internally to keep them rigid. This same method would undoubtedly work on a full-sized enclosure, but the higher forces and lower frequencies that we expect from full-sized speakers would mean that the reinforcements would be prohibitively large, heavy, and expensive to mold.

Best regards,

Bob Masta DAQARTA v3.50 Data AcQuisition And Real-Time Analysis

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