The perfect tumba
Posted: Tue Nov 08, 2011 1:56 pmPOST REMOVED BY THE AUTHOR
Both of my tumbas are 12.5", but I have played larger tumbas with open tones that sounded louder and deeper, and super tumbas that sounded bad. In general, however, I tend to agree with Leedy on this. A larger tumba could potentially sound deeper and louder, but needs a very thick skin, even and well broken-in. We are talking about the open tones here, not the bass you get by hitting the drum in the middle with the bottom opening raised off the floor. A well-played really thick skin can naturally have fewer high overtones and can give a more pure deeper bass, but only under certain circumstances. A thick skin is very stiff and around the inside of the bearing edge where the skin needs to flex when it vibrates, a new thick skin resists vibration due to this stiffness. This stiffness, which may be uneven around the circumference of the inner bearing edge, causes the skin to vibrate in other modes than the fundamental mode with the lowest frequency. This makes it sound less pure in tone, with more overtones. Playing a skin flexes the skin especially in that area of the inner bearing edge and over time breaks some of the microscopic fibers, making it more flexible in that critical area. This happens in months or couple of years on normal congas. On a super tumba with a really thick skin, it would take many years of hard playing to cause this break in. By hard playing I mean as a tumbador in a rumba with one person playing each drum, not as a tumba in a band, hit only occasionally as a tone. In most cases it would never get properly broken in and, as Leedy is saying, would sound bad forever. There is a lot of variability in this, and some skins just happen to be even and flexible enough to sound good from day one on a super tumba, so there are definitely exceptions to this. My friend went and picked a super tumba out of a room full of them at LP, and chose one with a really pure and deep open tone. Short of having that type of choice of skins, the sound of the open tone is hit or miss when you put a new skin on your super tumba.
The bass you get when you pick up the drum and hit a bass note in the middle of the skin (not an open tone) is less dependent on the skin, and really depends on the internal volume and length of the drum and the perpendicular (to the skin surface) displacement you produce when you hit the skin. I would have to disagree with Leedy on this, and say that this bass is deeper and louder on bigger drums, although picking up a super tumba with your legs every 2 bars to hit the bombo in a rumba gets tiring real fast with a very heavy drum. The bass of a 12.5" tumba is fine for my needs playing rumba, and in modern rumba the bass cajon gets the bombo anyway, much louder (although less deep) than the bass of the tumbador or tres dos. In salsa or timba, put the mic closer to the tumba because the lower tone naturally requires more sound level to be heard at the same loudness.
So, bottom line, 12.5" tumba is probably all you need, and if you don't have just the right skin on it, it can take many years to get the open tones on a bigger tumba to sound good, if it ever does.