The things that determine a drum’s sound
Whenever I’m planning a drum build with a client, I try to ask questions that’ll help me design the drum to fit the client’s own needs and goals. If I can get a clear picture of what they want, I can arrange the elements to make the drum able to do the job. But the sound of a drum isn’t something that’s easy to describe.
We talk a lot about drum sounds. We talk about how they “cut through the mix,” how they project, whether they’re tight and crisp, or fat and full, whether they have that elusive tone. And we use words like “crack” and “boom” and “splat” and “thump” to try to convey an idea of a sound concept that’s hugely subjective in the first place. Why do drums sound different? What are the variables and how are they used? What really determines how a drum sounds?
I’ve said before, and I’m saying again, and I’ll continue to say, that there are a lot of design details that work together (or sometimes against one another) to produce the performance and personality of a drum. So let’s talk about the ones that specifically affect the sound. Here’s my list, from most to least influential, of the major elements – not a complete list, by any means, but it covers the most important ones.
Bear in mind, this is an APPROXIMATE ranking. I‘ve been known to tweak the order, and your own list may look a little different.
1. Heads & tuning – Bottom line, the sound originates with the head, so this is by far the greatest factor in the sound. The head is perfectly capable of producing a viable sound just by being tensioned, even without a drum structure involved. Tuning can raise or lower all of the head’s sound together, or uneven tuning can cancel out some of the harmonics and put areas of the head out of phase. Also, there are dozens of head designs out there, including number of plies, thickness of plies, coatings, control rings, center spots, edge vents, etc. Each of these variables can change the original sound before it goes anywhere else.
2. Basic shell material (wood vs. metal vs. acrylic, etc.) – Yes, if you hit the shell it’ll make a sound. But we don’t play the shell, and its role is not to produce sound, but it does vibrate. The vibration of the head, passed along to the shell, influences the soundwaves inside the drum, absorbing or reflecting various frequencies. There are differences in the reflecting/absorbing characteristics of broad categories like wood and metal, so the general choice of material has a pretty significant effect on the overall tone.
3. Bearing edge profiles – The bearing edges are the point where the connection is made between the heads (rank #1) and the shell (rank #2). More contact means that more of the tone of the shell comes into play but with slightly shorter note. Less contact means more ring, but less shell tone.
4. Dimensions – Larger diameters produce lower pitches at similar head tension. Deeper shells produce slower response but more projection.
5. Shell thickness – A thicker shell has more mass and will produce a higher fundamental pitch. It will also make a louder drum, but with a corresponding loss of tone.
6. Shell construction (ply vs. steambent vs. stave, etc.) – This is also related to tone. Plywood has less resonance and tone because of more interruptions in the grain and alternating grain direction. Steambent is continuous horizontal grain, while stave is vertical grain that is only continuous vertically. All of these differences in the way vibration is transmitted result in differences in clarity of tone and level of resonance.
7. General wood density (soft vs. medium vs. hard) – While virtually all of the woods used for quality drum shells are hardwoods, there are still levels of hardness. Softer hardwoods have warmer, deeper tone and slightly less volume. Very hard woods generally have higher fundamental pitch and more projection.
8. Hoops – Depending on materials and design, hoops can focus a drum by reducing overtones or open it up. They can even out tuning or allow for more variation. It’s a matter of mass, stiffness, and capacity to vibrate.
9. Wood species – This is a smaller influence on the sound than the shell material differences mentioned earlier. It’s all wood, but different species offer differences in vibration absorption and reflectivity. More importantly, different species resonate to different spectrums of frequencies – making subtle differences in drum sound, related to tone more than just bright or dark.
10. Number of lugs – This has to do with the amount of hardware mounted on the shell, as well as with the evenness of tuning. Even mounting one lug will have a dampening effect on shell resonance, so fewer lugs allow a more open sound. It’s a minor difference, though, because the biggest change will be when the first lug goes on.
11. Type of lugs – This relates to how much mass gets added to the drum, and heavier lugs or large-footprint ones will make the most change in sound.
Of course I’ve left out one huge factor: the player. How an individual performer strikes the drum, the choice of sticks, etc., are a big part of the sound, but since these elements are not part of the instrument design, they’re not on this list. Also, I didn’t include mounting systems -– I know this can make a big difference in resonance and sustain, but it’s not, strictly speaking, part of the drum so I’m not counting it in the list. And remember, snare drums have some additional components that have significant audible effects.
Is that everything? Not by a long shot, but we’re getting into the area of differences that aren’t so easily audible and so that’s where this list is going to end.
