[Anthony]

MDF is also very stable for boxes. You don't have to account for wood movement in the design. A sealed box won't warp or crack with MDF like it would with solid wood.

Some also argue its damping properties, but those are debatable versus solid wood or baltic birch plywood. It is very heavy for it's volume, which helps.

Also, it's cheap and a good substrate for veneer. So you can tell everyone you made that speaker out of solid tiger maple

 

[Anthony]

Well, some of the best speakers in the business as still made with MDF. I believe Thiel makes their speakers with CNC cut and laminated layers of MDF. Very heavy, but also very well braced. And with the right veneer and/or finish can last a very long time. Baltic birch is also very good (and widely used).

As for being hard on tools, I have three levels of tool quality in my shop: hardwood, softwood/plywood, and MDF/particle board. With router bits, the new ones are only used on hardwood until they dull, then they are downgraded (and then eventually thrown away).

Now all that being said, my current project is going to be a hardwood speaker, but it's open baffle, so wood movement won't be a problem.

 

[Anthony]

I'll actually second that. I installed a full dust collection and air filter system in my shop just to deal with that (and I still prefer to rout MDF outside). I still use it, but that is a major downside.

Miner's have black-lung, I guess speaker builders have brown-lung