Availability: endangered species.

Weight/Hardness/Density: Varies greatly, weighing from 30 to 80 pounds per cubic foot. Its strength is similar to walnut, but it is not quite as hard.

Cost: Three to four times more than maple, and still increasing due to scarcity. Acacia Koa now fetches a price high enough that helicopters are being used to log it.

Comments: Ancient Hawaiian natives carved war canoes and surfboards from logs, and now use it for ukeleles and ceremonial drums.

Timbre/Tonal Color: Koa has a lower fundamental pitch than our maple comparison drum. More pitch bend on the attack than the maple, with a broader range of frequencies. Koa has more low end and body, due to this broader range of frequencies.

Dynamic Range: It went everywhere nicely. More low end kicked in around mf (medium loud) as we moved from pp (very soft) to ff (Very loud). The character sound of the drum didn’t change with this added low end, it just gave the drum a richer sound.

Tonal Range: Big. A broader, fuller and richer sound than that of the maple drum.

Tuning Range: Smaller tuning range than the maple. It didn’t go as loose before becoming tubby and boxy, and didn’t get as tight without choking. Although the tuning range was a bit small, when it was dialed in it was exceptionally sweet in sound.

Resonance/Decay: The principal note is equal to that of our maple drum, but the maple had a longer ring to it. Sweetspots on both drums were about the same.

Cross Stick: Cross stick area was equal in size and volume to that of the maple drum. No surprises here. The koa cross stick was deeper in pitch, which is what we expected given the lower pitch of the drum sound.

Volume: Very similar to maple in volume, just fuller and bigger sounding.

Sensitivity: Great at all volumes.

Comments: Because of the large variation in density between koa trees, we believe some of these characteristics could be quite different from one drum to another. Koa makes a beautiful drum. It has a velvet like “shimmer” to its appearance. The drum also had a nice feel to it, with a good stick rebound.

By Greg Gaylord & Robert “RB” Bowler.
Photo credit Frankie Frost.