A hi-hat, also spelled hihat or high-hat, is a combination of two cymbals, a foot-operated pedal which moves a rod which in turn moves one of the cymbals, all mounted on a metal stand. Hihats are an essential part of the standard drum kit used by drummers in many popular music (e.g. every genre of rock music) and traditional music (e.g. blues) styles. It consists of a mating pair of small to medium-sized cymbals mounted on a stand, with the two cymbals facing each other. The bottom cymbal is fixed and the top is mounted on a rod which moves the top cymbal towards the bottom one when a foot pedal is depressed (a hihat that is in this position is said to be "closed" or "closed hihats"). The hi-hat evolved from a "sock cymbal", a pair of similar cymbals mounted at ground level on a hinged, spring-loaded foot apparatus. Drummers invented the first sock cymbals to enable one drummer to play multiple percussion instruments at the same time. Over time these became mounted on short stands - also known as "low-boys" - and activated by foot pedals similar to those used in the 2010s. When extended upwards roughly 3' they were originally known as "high sock" cymbals, which evolved over time to the familiar "high-hat" term. The cymbals may be played by closing them together with the foot pedal, which creates a "chck" sound or striking them with a stick, which may be done with them open, closed, open and then closed after striking to dampen the ring, or closed and then opened to create a shimmering effect at the end of the note. Depending on how hard a hi-hat is struck and whether it is "open" (i.e., pedal not pressed, so the two cymbals are not closed together), a hihit can produce a range of dynamics, from very quiet "chck" (or "chick") sounds, done with merely gently pressing the pedal; this is suitable for soft accompaniment during a ballad or the start of a guitar solo, to very loud (e.g. striking fully open hats hard with sticks, a technique used in loud heavy metal music songs). While the term "hihats" normally refers to the entire setup (two cymbals, stand, foot pedal, rod mechanism), in some cases, drummers use the term "hihats" to refer exclusively to the cymbals.
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