Does MDF need to be painted?

You could use peel and stick veneer sheets. You can get a very nice look if you use real wood products and have a steady hand on a razor knife (straight cut and bevel together). Takes less time since you don't have to remove or mask drivers.

Take them to your local Panelbeater or Automotive paintshoppe - they can spraypaint them with ie high-gloss black or whatever colour you like.
If MFD is well sanded and sealed and sprayed with high-grade enamel it looks absolutly stunning. See the Revel Saloon speakers - that is how your subs should look after a good spray-job.

Do not use cheap sticky paper or such rubbish...

Kind regards,
Dewald Visser

You don't HAVE to paint them. But, if you care at all about the cosmetics, it's a good idea.

Bud Fried's own personal speakers are in bare, chipped, dirty particleboard. He gave them to me as a gift a few months prior to his passing. I initially toyed with the idea of doing something aesthetically, then changed my mind. Don't want to alter them from what was his reality.

Thanks for the info. I live in Arizona and it is hot and dry here, but ocassionally there is some humidity. As for sealing with polyurethane sealant or something like that, do I need to do the inside and outside (in other words dis-assemble the unit) or can I just do the outside?