In theory, adding complexity to the interior will give the drum a richer sound.
Dimpling the Inside
First we mark a line 3.5 inches down from the rim on the inside of the barrel. All carving or dimpling will be below this line so that the tacks won’t break through and leave shavings inside the drum. The dimple patterns are made with the drill press or a hand drill would work too. We use a half inch diameter drill bit and set the depth to 1/4 inch, to just barely drill into the wood.
