Drums produce indefinite or definite pitch depending on head tuning match and snares.

Evidence

The snare drum (or “side drum” in marching bands) has a set of metal wires stretched across its lower head (or “snare head”), which vibrate against the snare head when the drum’s upper head or “batter head” is struck. The snares can be dropped from the snare head by means of a lever to allow the drum to be used without the vibrating snare. Tom-toms, on the other hand, are often tuned so as to provide a more definite sense of pitch by matching more closely the tuning of the upper and lower heads on each drum. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1299

Categorization

• DEFINE: Defines snare head, batter head, and how snare wires work.