Treating the interior of a loudspeaker

[microx]

I am debating if it is better to varnish or paint the inside surfaces of a speaker or leave them plain, I think there are pros and cons for doing it. Solvents could degrade glues used in the drivers but on the plus side materials like MDF would be more resistant against humidity.
microx.

 

[speaker dave]

I'm not sure I would worry about it too much. If you are concerned with "outgassing" then let the cabinet sit for a week after you coat it.

I will say that veneered cabinets generally come with the inside veneered in a lesser grade wood. I was always told that was to prevent any warpage from dissimilar surfaces and moisture absorption. If in doubt, finish the inside similar to how you finish the outside.

David S.

 

[Charles Darwin]

I like to use this stuff:
Everbuild Product Range - Everbuild

It is water based, it seals and you can also use it to glue damping material like foam tiles.
Being rubberized bitumen it may also help damp things by itself.

But I don't know what the equivalent product in your place of residence would be.
Building merchants should know.