ELEMENTS OF SOUND
I am often asked for recommendations for a particular sound for a drum... warm, fat, sensitive, woody. I find it hard to think of any other subject so hard to describe as the voice of a musical instrument, it is just to subjective from one player to another. Determining the specs for your next drum can be a difficult choice. But in the end, it comes down to building the drum with your personal taste in both the voice and appearance.
The following is a compilation of general principles I hope will be useful in understanding the various factors to determine how to spec your drum shell(s).
The drum shell is the foundation for the eventual instrument voice, used in concert with a variety of other factors that will determine the drums sound such as the bearing edges, hoops, head selection, tuning and wires. As with any shell type, be it metal, ply, acrylic or other material, a stave shell has its own unique sound. What is different about a stave shell is the fact that glue is almost nonexistent, the orientation of the wood being vertical allows the energy of the heads to travel down and through the wood fibers in it's natural state to interact with the air mass being moved inside the shell in a way no other shell can.
There are a few basic principals to consider when making your selections for a shell: the wood hardness, shell thickness, size, bearing edges...and of course its appearance.
Wood hardness is rated via the "Janka Hardness Scale". This test was developed by the flooring industry by measuring the pounds force required to embed an 11.28 mm (0.444 in) steel ball into wood to half the ball diameter. The higher the rating number, the more pounds force is required, thus the harder and more dense the specie. The lower the rating number the softer, less dense. The effect of a particular species density as it relates to use as a drum shell is pretty simple, the harder the specie the higher its fundamental pitch, the softer the lower the pitch.
See the list of Available Species for detailed information on specific wood species.
The shell thickness has a unique effect. The thinner the shell the more it will vibrate/resonate bringing the fundamental tone of a particular specie more into focus. A thicker shell will be less resonate, and its fundamental pitch less focused, but will increase attack and projection. While some offer 1" and thicker shells, I have found that increasing a shells thickness more than 1/2" (13mm) has little to no value in changing the shells voice, it just adds weight and special hardware mounting considerations.
See the Shells page for detailed information on available shell thicknesses.
Obviously a shell with a larger diameter will be lower in pitch, but the shell depth can come into play as well. Since a drum is essentially moving air when the head is struck, both the volume of space and distance between batter and resonate heads has an effect. Generally speaking a deeper shell will result in a bigger/fatter sound, whereas a shallow shell will have a tighter feel and increased sensitivity because there is a shorter distance between batter and resonate head reaction when played. This applies to snares, toms and kicks.
The bearing edge serves three purposes;
- To properly seat the head true flat which is very important.
- The means to transfer energy through the drum shell.
- To control or create more overing in the drum heads.
Bearing edges must begin with a flat, trued edge. Once the edges are milled, the edges should be sanded for final true on flat surface so as to have zero gaps when the head is tensioned.
The style of the bearing edge will have a dramatic impact on the sound of the drum.
A rounded counter cut (outer edge) will seat the head in it's most natural state, it allows more contact area with the shell and I find will also keep its tuning much better. This is a plus when you consider the bearing edge on a stave shell is on the end grain. This allows maximum transfer of energy through the shell fibers that create that stave drum tone. All other wood shell types loose much of this energy and rely mostly on the air mass inside to resonate the shell. If you prefer a more controlled focused sound, this is your edge.
A 45 degree counter cut (outer edge) also has contact with the counter cut slope but much of the tension is on the apex . While it is argued this allows more resonance, it also adds overing. To increase the overing of the heads, simply move the apex of the bearing edge outward by use of a smaller counter cut 45. If you prefer more sustain/overing this is your edge.
See the Services page for detailed information on the bearing edge profiles offered.