I just finished a small cab build for my Quilter. I wanted to test my theory that a small speaker will work better for quiet play. The cab is 12h x 16w x 10d and is birch plywood. I used an 8 inch Celestion TF0818. The TF0818 is the speaker Quilter uses in his Mach 2 combos and is rated at 100 watts. I was not too pleased at first, but as the speaker plays in, it is getting very nice. It sounds really good for low volume play and really complements the SB US very well. It's still unfinished....I'm thinking about staining it blue.