The bodhrán or Irish frame drum is a small handheld drum consisting of a goatskin playing surface stretched over a wooden frame. It resembles a tambourine, minus the brass jingles, and has been referred to as the "poor man's tambourine."
The drum can be struck with the hand, "finger style," but most Celtic percussionists strike the drumhead with a double-headed knobbed stick, known as a tipper, a cipín or beater. Several different types of wood are used in bodhran manufacture, including redwood, rosewood, birch, oak, ash, and willow. Drumhead materials have also varied over the centuries of bodhran history: sheepskin, donkey and even greyhound skin are said to have been capable of rendering fine drum tone.
It is common for drum makers to insert wooden crossbars spanning the underside of the drum frame. Since the rim was originally made from wood bent while still green, these crossbars had a functional purpose, to prevent warping as the wood dried and aged. Due to more sophisticated wood-bending techniques, modern bodhrans are not as susceptible to warping of the rim: Crossbars are thus ornamental and traditional rather than functional, and if desired, they can generally be removed without compromising the structural integrity (and the sound) of the instrument.
Today, bodhrans can be made to be tunable, allowing the player to tune the pitch and compensate for shifts in temperature or humidity that may affect the sound of the drum. The bodhran maker may insert up to a dozen tuning screws into a metal ring surrounding the drumhead, enabling the player to tune it with ease. Some players prefer to make manual tuning adjustments utilizing the hand holding the drum; they reach inside and put extra pressure on the drumhead, thereby tweaking the skin tension and altering the pitch.