Each speaker base is a 14X14 piece of 3/4" mdf. I rounded the edges and applied a 1/2" roundover to the front and sides. The discoloration is a 50/50 mix of carpenters glue and water which I painted on to reduce the edges' inclination to adsorb the paint, which I will spray on tomorrow. The best paint I have found for speaker cabinets is Rustoleum Satin Black. Like the varnish on the cabinets, you apply three coats, wait 72 hours, sand, and apply one final coat.