From:
Chip Wetzel <cjwetzel

shaw.ca>
On my own EUB, I used a solid chunk of 2" thick Ash, and then added a 1/4" layer of curly maple on the face. I find that as in electrics, the ash is a good, solid, 'thunky' sound, and the curly maple face, while adding beauty, seems to give a bit of brightness and clarity. Another good possibility is mahogany, preferrably Honduran - that should give a very solid, warm tone. I think in retrospect, I would now have chosen mahogany to counter the effects of the piezo-pickup's tendency to be a little too clean.
GabrielGuitars