Drum tuning

Drum tuning is the process of adjusting the frequency or pitch of a drum. Although most drums are unpitched instruments, they still have a fundamental pitch and overtones. Drums require tuning for a variety of reasons: to sound good together as a kit, to sound pleasing as an individual drum, to achieve the desired amount of ringing and resonance, and to produce the sound that fits the music. Some drums such as timpani and rototoms are tuned to a definite pitch. Drums are tuned by tightening or loosening the tension rods or ropes, which control the tension on the drumhead. Additional techniques such as muffling may also be used to affect resonance.
Tuning toms is the act of ensuring that:
When tuning a drum, drummers must keep in mind that the top (batter) head controls attack and ring, while the bottom head controls resonance, sustain, overtones, and timbre.
A drum key or drum tuning key is a tool used to adjust the tension rods of a drum, to change the pitch. It is also used to adjust drum hardware.
The most common pattern fits a square-head tension rod. There are minor variations of size between makers.
When tensioning a head, the tensioning rod closest to the tensioner should be tightened first. The reason for this is to keep an even tension across the drum head, which is impossible to do if the lugs are tightened differently. Next, the tension rod opposite the first lug is tightened by the same number of turns. The process is repeated for the remaining lugs in order, moving from one side of the head to the other.
When all of the rods are tightened, the first rod is once again tightened, and the process is repeated once again for each rod until the head is free of wrinkles and a very low tone is produced when hit.
The rods are further tightened in order and incrementally, by no more than a quarter turn each time. From time to time, the head is tapped next to each tension rod and the rods are tightened and loosened so that the tones are the same all around the drum.
The procedure is repeated until the head has the desired pitch. At times it may be desirable to use a specific key or individual musical notes to tune each drum to, creating more melodic tones and a more musical sound to the drums. The head is tapped once more around the edge to ensure even tuning. If double-headed drums are used, the procedure needs to be repeated with the bottom head.
Single-tension is one of several ways to apply the necessary tension to drum heads. Single-tension systems largely replaced the ancient rope-tension methods in the late 19th century and are still used today in lower-priced drums for student use. In this system, one long tension rod with a threaded end extends through the hoop holding the top drum head and then down outside the drum shell to a threaded hole in the bottom hoop. There usually is a small guide halfway down on single-tension drum shells to keep the tension rods straight. In older drums, the hoops are often held tight by separate clamps through which the threaded tension rod fits. Tension is applied by turning a special key that fits into a hexagonal drive, but many bass drums (especially those models designed for concert use) have permanent wing-nuts permanently affixed to each tension rod, even on double-tension drums.
Double-tension is a method of applying tension to drum heads. Drum manufacturers use several methods to apply tension to drum heads; the preferred way is to tighten the heads with a hoop that is held tight to the drum shell with a number of individual threaded rods which connect to stanchions mounted with bolts onto the outside of the drum shell. When there are individual stanchions for both the lower head and the upper "struck" head, or when there is one common center-mounted stanchion that accepts the threaded rods from both the upper and lower drum heads, that is said to be a double-tension drum.
Rope-tension is the oldest system for applying tension to drum heads and was the standard system used until the late 19th century. A long rope (or less commonly, a series of ropes) is passed alternately between the top and bottom drum head hoops that are held to the shell by clamps that incorporate holes for the rope(s). The ropes are made tighter by sewn-together loops called 'ears', usually made of leather, which slide along the rope to pull the hoops inward, tightening the drum heads. These ears remain in position due to the tension of the rope. Drum heads tightened in this manner are not as tense as more modern single-tension or double-tension systems, but offer a historically deep tone in keeping with the heritage of certain music, such as Pipe and Drum Corps, Fife and Drum Corps, and historical military bands such as Field Music ensembles that were common during the American Revolutionary War, the War of 1812, and the American Civil War periods.
Other systems of rope tuning are used outside the Western tradition, such as the "Mali weave" used to tune the djembe.
Many percussionists prefer a more dry sound with less ring. There are many different techniques that can be used to reduce ring.
One approach is to loosen the batter head a quarter to a half turn. Another way is to either increase or decrease the pitch of the bottom head so that it's different from the pitch of the top head. Either of these approaches produces a slightly more dry, funkier sound.
If unwanted ring is not eliminated—or if these types of heads produce unwanted tones—then there are multiple external muffling techniques that may be used, including:
Wang C.Y. Journal of Sound and Vibration, February 1999, vol. 220, no. 3, pp. 559–563, Ingenta.
Laura P.A.A.; Rossit C.A.; Bambill D.V. Journal of Sound and Vibration, December 2000, vol. 238, no. 4, pp. 720–722, Ingenta.