DEFINITIONS

A - D
2-foot or 2’	for organs, a rank of pipes each of which produces the pitch two octaves above the pitch of the key on the keyboard used to sound it [see ‘foot’]
4-foot or 4’	1) for organs, a rank of pipes each of which produces the pitch an octave above the pitch of the key on the keyboard used to sound it; 2) for harpsichords, a choir of strings each of which produces the pitch an octave above the pitch of the key on the keyboard used to sound it [see ‘foot’]
8-foot or 8’	1) for organs, a rank of pipes each of which produces the same pitch as the key on the keyboard used to sound it; 2) for harpsichords, a choir of strings each of which produces the same pitch as the key on the keyboard used to sound it [see ‘foot‘]
aerophone	[wind instrument] musical or sound-producing instrument that has as its primary sounding or vibrating element a standing air wave in a cavity or an airstream-activated interruptive reed
aggregate gong	[pan, steel drum] an open vessel idiophone the apex of which is a faceted concave depression each facet of which is capable of producing a distinct pitch
air column	a tubular space in which the articulated volume of air is excited into an audible standing wave
airflow interruptive system	on aerophones, a single or multiple reed, a player’s buzzing lips, or a sharp edge functioning as a transducer to transform the steady flow of airstream energy into the intermittent bursts of energy that generate an audible standing wave in the cavity/bore of an instrument [see ‘transducer’]
barrel drum/shell	a tubular membranophone shell the end openings of which are of the same diameter and whose sides are symmetrically arched outwards, like those of a barrel
basso continuo	see ‘figured bass’
bell	(1) an open vessel idiophone the rim of which is most active when struck while its apex is least active; (2) the flaring distal terminus of an aerophone’s tubing
board zither	a chordophone the string carrier of which consists of a flat sturdy frame to which the string ends are anchored and held in tension; one face of frame is covered by a thin wooden board that serves as a soundboard; the plane of the strings is parallel to that of the soundboard
bore	the interior space of a tube; for aerophones an instrument’s bore can be described precisely in terms of the measurement of its diameter or relatively in terms of how that diameter changes over the length of the instrument from its excitation end to its distal end with descriptors such as cylindrical, conical, and tapering [see ‘cylindrical bore’, ‘conical bore’, and ‘tapering bore’]
boss	a raised dome or knob at the apex of a gong idiophone that is struck
bow zither	a chordophone the string carrier of which is a bow-like flexed length of material the ends of which are connected by a string that is held in tension by the elastic force of the carrier
brass	an umbrella label of the Western music tradition that subsumes a wide variety of lip-reed aerophones made of brass
bridge harp	a chordophone the sound carrier of which consists of a joined resonator and a neck; strings are tensioned between an endpin on the resonator wall and the neck, and pass over the sides of a tall pressure bridge standing on the resonator soundboard that organizes the strings into two parallel planes that are perpendicular to the plane of the resonator soundboard
bulging-conical drum/shell	a tubular membranophone shell the end openings of which are of different diameters and whose sides bulge outwards from the wider opening before tapering to the narrower opening
bullroarer	a non-idiophonic interruptive aerophone in the form of a flat rectangular- or ovoid-shaped slat of wood attached to the end of a string used to whirl the slat, which also rotates on its own axis, through the open air [see ‘interruptive free aerophone (2)’]
bushing peg	a chordophone string tension-control device in the form of a cylindrical metal shaft that passes through a metal bushing-lined hole in the side or back of an instrument’s headstock and held in position by friction; one end of a string is attached to and wound around one end of the shaft, which is rotatable by hand using the button/knob at the other end of the shaft
choir	for harpsichords, a row of strings organized in a horizontal plane and brought into play as a group, each string corresponding to a single key on the instrument’s keyboard [see ‘stop’]
chordophone	[string instrument] musical or sound-producing instrument that has as its primary sounding or vibrating element one or more tensioned string/s held in tension by a string carrier
chromatic brass	single air-column lip-reed aerophone on which it is possible to produce the chromatic scale (which consists of twelve pitches each separated from one another by a semitone [minor second] in the span of an octave) by means of rapidly changing the length of the instrument’s air column with the aid of a mechanism (either vent holes, a telescoping slide, or one or more piston or rotary valves)
chromatic labrosone	see ‘chromatic brass’
clarinet	(1) a generic term for any ‘single reed’ or ‘percussion reed’ aerophone; (2) English language name for the family of standard cylindrical-bore end-blown single-reed aerophones of the Western music tradition
compound-conical drum/ shell	a tubular membranophone shell the end openings of which are of the same diameter and whose sides symmetrically taper outwards to a midpoint, like two cones joined at their larger openings
concussion	crashing together two sonorous objects of similar design
concussion reed	see ‘double reed’ and ‘quadruple reed’
conical bore	a general bore profile for aerophones in which the diameter of the bore gradually increases over the entire length or nearly the entire length of an instrument
conical drum/shell	a tubular membranophone shell the end openings of which are of different diameters and whose sides taper evenly from the large opening to the small one, like a truncated cone
counterhoop	1) a hoop or ring encircling a drum shell that due to its immobility serves as the source of counterforce in creating tension in a drumhead; 2) commonly used for what is referred to on this site as a ‘tension collar/rim’ [see ‘tension collar/rim’]
course	see ‘string course’
crook	a straight, looped, or coiled length of cylindrical tubing that when inserted between the mouthpiece and the lead pipe of a lip-reed aerophone lowers the fundamental pitch of the instrument by a specific interval
cylindrical bore	a general bore profile for aerophones in which the bore diameter remains constant over the entire length or, if there is a bell, nearly the entire length of and instrument
cylindrical drum/shell	a tubular membranophone shell the end openings of which are of the same diameter and whose sides are straight, like a pipe
cylindrical-conical drum/shell	a tubular membranophone shell the end openings of which are of different diameters and whose sides are cylinder-like at the larger opening end and conical-like at the smaller opening end
cymbal	generic term for individual or paired contoured metal plate idiophones with relatively flat rims sounded either by percussion (for single cymbals) or concussion (for cymbal pairs) or both percussion and concussion (for some cymbal pairs)
definite pitch	a sound with a structured blend of harmonic partials above a fundamental frequency [see ‘pitch’]
direct fastening	the edge of an unframed membrane is attached directly to the shell of a drum or the resonator of a chordophone with glue, tacks/nails, or pegs
direct lacing	the lacing technique used to attach an unframed membrane to its drum shell or its chordophone resonator; lacing passes through roughly equidistantly spaced holes punctured into the membrane near its edge and alternately over or through a relatively immobile structural component providing a counterforce
distal end	the end of a tube furthest from the excitation mechanism
double reed	(1) an excitation mechanism [see ‘transducer’] for aerophones that consists of the thinly shaved ends of two pliant reeds secured at their other end to a short length of pipe that is inserted into the end of a tube; (2) any aerophone with a double reed excitation mechanism [see also ‘oboe (1)’]
drum	(1) see ‘membranophone’; (2) sometimes used in the name of certain percussion idiophones [see ‘slit drum’]
drumhead	the primary sounding element of a membranophone consisting of an elastic membrane held in tension [see ‘unframed membrane’ and ‘framed membrane’]
duct	a constructed channel in an aerophone mouthpiece used to direct the airstream against a sharp edge serving as the excitation mechanism of the instrument
dynamics	that parameter of a musical note perceived of as its loudness, intensity, or volume
E - H
edge aerophone	an aerophone or part of an aerophone in which an airstream is directed against a sharp edge that functions as a transducer [see ‘flute (1)’]
electro-acoustic instrument	an electrophone the electrical signal of which is transduced from an acoustical source, such as vibrating bars, strings or air-columns
electromagnetic pickup	a type of transducer consisting of an electromagnet in close proximity to a vibrating object (with iron content) the movement of which in the magnetic field creates a varying electrical voltage
electronic instrument	an electrophone in which the electrical signals being processed are generated by electronic oscillators or through digital synthesis
electrophone	an instrument that generates and processes electrical signals that are passed to a loudspeaker to produce sound [see ‘electro-acoustic instrument’ and ‘electronic instrument’]
end-blown	aerophone for which the airstream enters its air column through an end of the instrument
excitation mechanism	see ‘transducer’
fastening	the attaching of membranes to membranophone shells or chordophone resonators [see ‘direct fastening’ and ’indirect fastening’]
figured bass	notation and performance practice used during the Baroque era (c. 1600-1750 CE) that included a fully notated bass line beneath which numeral and accidental signs were added as a shorthand for communicating chord quality and inversion to extemporizing performers of harmony-producing instruments (also called ‘basso continuo’ [Itl] and ‘thoroughbass’ [Eng])
fingerboard	a flat or slightly arched surface of a chordophone neck just under the plane of strings against which a string course is pressed to articulate a new vibrational endpoint, thus changing the active length of the string/s and the pitch produced
fingerhole	a hole drilled through the wall of an aerophone’s body that can be covered and uncovered with the performer’s fingertip or a pad; the opening and closing of fingerholes modifies the standing wave form in the instrument’s air cavity and results in different pitches being sounded
flesh hoop	(1) term used by Western drum makers for the rigid wood or metal hoop to which a membrane is permanently attached; (2) the hoop-reinforced membrane soundboard of a banjo
flexing	stressing/bending and releasing of elastic sonorous object/s to sound it/them
flute	(1) a generic term for any ‘edge aerophone’; (2) English language name for the standard side-blown edge aerophone of the Western music tradition
foot	for organs and harpsichords, a means of marking relative pitch register between ranks of pipes or choirs of strings [see ‘2-foot or 2’’, ‘4-foot or 4’’, and ‘8-foot or 8’’]
fork	mechanically-operated device on pedal harps consisting of vertical pins mounted on rotating discs activated by foot pedals; when brought into action they serve as ‘tension stubs’ to shorten the full vibrational length of a string and in so doing raise the pitch of the string
frame drum/shell	a tubular membranophone shell in the form of a frame, round or polygonal, the depth of which is less than a quarter of the diameter/width of its openings
frame harp	a chordophone the string carrier of which consists of a joined resonator and neck and a post/pillar that connects the distal ends of the resonator and neck to form a rigid frame; tensioned strings are stretched between the resonator soundboard and the neck, the plane of tensioned strings is perpendicular to the plane of the resonator soundboard
framed membrane	a drumhead the edge of which is reinforced [see ‘flesh hoop (1)’]
free reed	(1) [interruptive reed] a pliant reed/tongue cut from or attached at one end to a closely fitting aperture in a plate (usually of metal) mounted on the wall of a tube or on a block; (2) a generic term for any airstream-activated interruptive-reed aerophone
free stopping	firmly pressing against a string course with a fingertip, fingernail, or solid object, but not against a surface, to articulate a new vibrational endpoint, thus changing the active length of the string/s and the pitch produced
fret	a raised ridge imbedded across a fingerboard and against which a string course is pressed to articulate a new vibrational endpoint, thus changing the active length of the string/s and the pitch produced
fretless fingerboard	a smooth-surfaced fingerboard with no frets; the player must determine where to press a string against the fingerboard to produce the desired pitch
fretted fingerboard	a fingerboard with carefully positioned raised frets running across it that assist the player in adjusting the vibrational length of a string so that desired pitches can be produced
friction peg	a chordophone string tension-control device in the form of a slightly tapering wood or plastic shaft that passes through a hole in the side or back of an instrument’s headstock and that is held in position by friction; one end of a string is attached to and wound around one end of the shaft, which is rotatable by hand using the button/knob at the other end of the shaft
friction pin	a chordophone string tension-control device in the form of a sturdy metal pin partially imbedded in a block of wood and held in position by friction; one end of a string is attached to and wound around the pin, which is rotatable with the aid of a metal key that fits over the exposed end of pin
fundamental	see ‘fundamental partial’
fundamental partial	the lowest and generally strongest frequency in a note, the one that gives rise to the perception of a note’s pitch
goblet drum/shell	a tubular membranophone shell the end openings of which are of different diameters and whose sides have a bowl-like profile from the larger opening to their midpoint and a stem-like cylindrical or conical profile from there to the smaller opening, like a goblet
gong	an open vessel the apex of which is most active when struck while its rim, typically sharply turned inward, is least active
gong chime	an idiophone comprised of several gongs of graduated size each producing a distinct pitch; typically used as a melodic instrument
half-spike lute	a chordophone the string carrier of which is bi-sectional, consisting of neck and resonator with the plane of strings running roughly parallel to that of the resonator soundboard - the base end of the neck penetrates one sidewall of and terminates inside the resonator
harmonic partials	partials in a sound the frequencies of which are integer multiples of the frequency of the sound’s fundamental partial
harmonic series	an orderly series of frequencies including the fundamental and harmonic partials that are present simultaneously in a note of definite pitch or that can be produced discreetly on many chordophone and aerophone instruments
harmonics	(1) for chordophones, the selection of harmonic partial overtones by lightly touching a vibrating string at specific nodes in its vibrational movement; (2) for tubular aerophones, making speak in a given length of tubing the frequency of an harmonic partial overtone of that tube length’s fundamental partial
harp	(1) a chordophone string carrier design consisting minimally of a joined resonator and neck; tensioned strings are stretched between the resonator sound-table and the neck, the plane of tensioned strings is perpendicular to the plane of the resonator soundboard; (2) English language name for diatonic and pedal harps used in Western folk and classical music traditions
head	see ‘drumhead’
heteroglot	one end of an elongated piece of pliant material is attached but not integral to a frame made of either similar or different material
horn	(1) a generic term for any ‘lip reed’ aerophone; (2) English language name for the standard conical-bore lip-reed aerophone of the Western music tradition made of brass, with or without valves
hourglass drum/shell	a tubular membranophone shell the end openings of which are of the same diameter and whose sides are symmetrically in-curving so that the diameter at the middle of the shell is less than at its ends, like an hourglass
I - N
idioglot	a tongue articulated by cutting an elongated rectangular outline into the material that constitutes its own frame, one end of the tongue remains integral with the frame, the other can flex when an airstream is applied to it
idiophone	[e.g., keyboard percussion, bell, gong, rattle, etc.] musical or sound-producing instrument that has as its primary sounding/vibrating element solid, sonorous material (e.g., wood, bamboo, gourd, earthenware, metal, or plastic)
indefinite pitch	a sound with a wide spectrum of inharmonic partials none of which is dominant enough to be perceived as an identifiable pitch
indirect fastening	the edge of an unframed membrane or the reinforcing hoop of a framed membrane is attached indirectly to the shell of a drum or the resonator of a chordophone [see ‘lacing’, ‘direct lacing’, ‘indirect lacing’, and ‘tension collar’]
indirect lacing	the lacing technique used to attach a framed membrane to its drum shell or its chordophone resonator; lacing passes through roughly equidistantly spaced holes punctured into the membrane and over its reinforcing hoop, and alternately over or through a relatively immobile structural component providing a counterforce, so that when tightened the lacing places force on the membrane hoop
inflected pitch	a sound of relative or definite pitch which is perceived to rise or fall in the course of its decay
inharmonic partials	partials in a sound the frequencies of which are not integer multiples of the frequency of the sound’s fundamental partial
integral lute	bi-sectional string carrier consisting of neck and resonator with the plane of strings running roughly parallel to that of the resonator soundboard - the resonator and neck of the lute are carved from a single block of material
interruptive free aerophone	an agent produces periodic vibration either by itself or in open air: (1) idiophonic interruptive aerophone--the agent, in the form of a lamella set in a closely-fitting slot, vibrates when activated by an airstream [see ‘free reed’]; (2) non-idiophonic interruptive aerophone—the edges of the agent, which itself does not vibrate but which rotates on its own axis, produce periodic vibration when the agent is whirled through open air [see ‘bullroarer’]
interruptive reed	see ‘free reed’ and ‘interruptive free aerophone (1)’
jack	part of the sounding action of a harpsichord to which a plectrum is mounted; it is propelled upward when a keyboard key is depressed, bringing its plectrum into contact with a string
joined lute	a chordophone the string carrier of which is bi-sectional, consisting of neck and resonator with the plane of strings running roughly parallel to that of the resonator soundboard - the base of the neck is joined to the sidewall of the resonator
key	(1) a single lever mechanism in a keyboard [see ‘keyboard (1)]; a single oblong bar of sonorous material on a xylophone or a metallophone [see ‘keyboard (2)’]
keyboard	(1) in the Western music tradition, an orderly arranged series of side-by-side levers (called keys) that when depressed activate the mechanical or electrical actions necessary to sound an individual sound producing component (a string course, an organ pipe, a metallophone key) of an instrument - keys are arranged in two tiers to produce a one-octave chromatic scale pattern that can be repeated as many times as necessary, always in an ascending order with the lowest octave to the player’s left; (2) the orderly side-by-side arrangement of the sounding elements of an instrument, especially xylophones, metallophones, and lamellaphones
keyboard instrument	an umbrella label of the Western music tradition that subsumes aerophone, chordophone, and idiophone instruments on which pitch selection is made by depressing lever mechanisms (called ‘keys’) [see ‘keyboard (1)’]
keyboard percussion	in the Western music tradition, xylophones and metallophones the keys on which are arranged in the fashion of a keyboard (sounding objects are arranged in two tiers to produce a one-octave chromatic scale pattern that can be repeated as many times as necessary, always in an ascending order with the lowest octave to the player’s left)
knob	see ‘boss’
labrosone	organological term for ‘lip-reed aerophone’; derived from the Latin words labra (lips) and sonare (sounding). [see ‘natural labrosone’ and ‘chromatic labrosone’]
lacing	fastening technique used to attach membranophone drumheads to shells or chordophone membrane soundboards to resonator boxes/bowls using a cord or string (of wire, rawhide, natural or synthetic rope) to draw together a membrane edge, membrane frame, or tension hoop and a structure providing a counterforce [see ‘direct lacing’ and ‘indirect lacing’]
lamellaphone	generic term for idiophones the vibrational element of which is a tongue (‘lamella’ means ‘plate’ in Latin) of elastic material; one end of the tongue is anchored or integral to the instrument’s body, the other is free to vibrate in response to being plucked or struck
lamellophone	variant spelling of ‘lamellaphone’
lip reed	an excitation mechanism [see ‘transducer’] for aerophones that consists of the tensed lips of the player placed over a hole in the sidewall of an instrument’s cavity or over the end of a tube, with or without a cup mouthpiece [see also ‘labrosone’]
lute	(1) generic name for chordophones with a bi-sectional string carrier consisting of a resonator and neck; the plane of its strings runs roughly parallel to that of the resonator soundboard surface; (2) English language name for the family of short-necked plucked lutes with tear-drop shaped resonators of Medieval, Renaissance and Baroque Europe
lyre	(1) a type of chordophone [see ‘yoke lute’]; (2) a music-holding attachment for marching band instruments
m[number]	interval designation of the ‘minor’ quality (e.g., m6 = minor sixth) in the Western diatonic scale system
M[number]	interval designation of the ‘major’ quality (e.g., M2 = major second) in the Western diatonic scale system
machine head	a chordophone string tension-control device in the form of a cylindrical metal shaft that passes through holes in the side or back of an instrument’s headstock and that has a pinion gear at one end that is rotated with a worm screw mounted on a metal plate; one end of a string is attached to and wound around the shaft, which is rotated by turning the worm screw button
membrane	a thin, elastic sheet of material, often the skin of a mammal or reptile, but also of man-made products, used as a drumhead on membranophones and as a resonator sound board on some chordophones
membranophone	[drum] musical or sound-producing instrument that has as its primary sounding/vibrating element one or more tensioned membrane/s
metallophone	generic term for struck idiophones with solid oblong keys made of metal as their sounding components
mouthpiece	a component, usually removable, of single-reed and lip-reed aerophones that is located at the blowing end of an instrument’s air column and serves as the juncture between the player’s mouth and the instrument proper; for single-reed aerophones the reed (the instrument’s airflow interruptive system) is attached to the mouthpiece, for lip-reed aerophones the lip-reed (the player’s lips, the instrument’s airflow interruptive system) is pressed against the bowl-shaped end of the tubular mouthpiece
multiple reed	the thinly shaved ends of two or more pliant reeds secured at their other end to a short length of pipe that is inserted into the end of a tube [see ‘double reed’ and ‘quadruple reed’]
natural brass	single air-column lip-reed aerophone; pitch selection is basically limited to partials in the harmonic series [see ‘natural horn’ and ‘natural trumpet’]
natural horn	single air-column lip-reed aerophone with a conical bore; pitch selection is basically limited to partials in the harmonic series; fundamental length may be altered by inserting crooks of varying lengths [see ‘conical bore’ and ‘crook’]
natural labrosone	see ‘natural brass’
natural trumpet	single air-column lip-reed aerophone with a cylindrical bore; pitch selection is basically limited to partials in the harmonic series; fundamental length may be altered by inserting crooks of varying lengths [see ‘cylindrical bore’ and ‘crook’]
neck	a component of a chordophone string carrier one end of which is connected to or passes through the instrument’s resonator; one end of an instrument’s strings is either directly attached to its neck or to a block [see ‘pegblock’] at its distal end
note	a sound with duration, intensity [see ‘dynamics’], pitch [see ‘pitch’], and tone quality [see ‘timbre’]
nut	a component of a chordophone that marks the end of the vibrational length of a string but that does not transmit the vibrational energy of the string to the surface of a resonant cavity
O - Q
oboe	(1) a generic term for any ‘double reed’, ‘concussion reed’, ‘quadruple reed’, ‘multiple reed’ aerophone; (2) English language name for the standard conical-bore end-blown double-reed aerophone of the Western music tradition
open harp	a chordophone the string carrier of which consists of a joined resonator and neck; tensioned strings are stretched between the resonator soundboard and the neck, the plane of tensioned strings is perpendicular to the plane of the resonator soundboard
overblowing	for tubular aerophones, the act of making speak in a given length of tubing the frequency of an harmonic partial overtone of that tube length’s fundamental partial through a combination of manipulating airstream pressure and the airstream’s movement against or through the instrument’s excitation mechanism
overtone series	see ‘harmonic series’
overtones	any partial, harmonic or inharmonic, above the fundamental partial of a note
P[number]	interval designation of the ‘perfect’ quality (e.g., P4 = perfect fourth) in the Western diatonic scale system
partials	vibrational components of a sound, including the sound’s fundamental frequency and its overtone frequencies
partitioning bridge	a pressure bridge that divides the vibrational length of a string into two shorter vibrational lengths one each side of the
pedal tone	for Western lip-reed aerophones (brass instruments) the fundamental partial of the harmonic series for a given length of tubing
pedestal drum/shell	a tubular membranophone shell the end openings of which are of different diameters and whose sides are cylinder-like overall except for a sudden constriction near its pedestal- or foot-like base
pegblock	a section of a lute located at the distal end of an instrument’s neck and housing its tension controlling devices (tuning pegs, machine heads)
percussion	(1) striking a sonorous object with a non-sonorous object; (2) an umbrella label of the Western music tradition that subsumes a wide variety of idiophones and membranophones
percussion reed	see ‘single reed’
Périnet valve	an 18th century mechanical piston valve design for brass instruments in which an instrument’s air column passes laterally through the cylindrical valve casing/s and with which an additional segment of tubing can be added to the basic length of an instrument’s air column [see Of Tubes, Slides, and Valves--How Brass Instruments Work]
pickup	a transducer that converts vibrational energy into an electrical signal
piezoelectric pickup	a type of transducer that is in direct contact with the vibrating source and generates a voltage when stressed
pillar	see ‘post’
pin block	a component of the string carrier of a chordophone consisting of a block of wood (integral or laminated) into which friction pins are imbedded that are used to adjust string tension/tuning [see also ‘friction pin’]
piston valve	a mechanical device in the form of a piston within a cylindrical casing; by depressing the piston an additional length of tubing is added to the basic acoustical length of the instrument and brings a new combination of pitch possibilities into play; a spring in the cylinder or in the piston itself returns the piston to its neutral position when the performer stops depressing it [see ‘Stölzel valve’ and ‘Périnet valve’]
pitch	the frequency of a note’s fundamental partial, which situates it on a frequency-defined auditory spectrum as being relatively higher or lower in comparison to notes with other frequencies; pitch can be described numerically by the frequency of its fundamental or, when part of an orderly system of pitches for a given musical tradition, by some other labeling (a letter name, a cipher, its position on a notational stave, etc.)
plucking	see ‘flexing’
post	a component of the string carrier for a closed harp; a pillar/post that connects the base end of the resonator to the distal end of the neck
pounding	see ‘stamping’
pressure bridge	a component of a chordophone that stands on an instrument’s soundboard and is held securely in place by the downward pressure of the tensioned string/s that pass over it; it serves both to mark one end of the vibrational length of the strings and to transmit the vibrational energy of the string/s to the resonator soundboard
pressure stopping	any point along the vibrational length of a string course may be firmly pressing a string course with a fingertip or fingernail against a fingerboard to articulate a new vibrational endpoint, thus changing the active length of the string/s and the pitch produced
quadruple reed	an excitation mechanism [see ‘transducer’] for aerophones that consists of the thinly shaved ends of four pliant reeds secured at their other end to a short length of pipe that is inserted into the end of a tube
R - S
rank	for organs, a row of pipes of the same type, each pipe corresponding to a single key on the organ keyboard [see ‘stop’]
rattle	generic term for any idiophone sounded with a shaking motion; most rattles are closed vessels with internally- or externally-situated seed beaters
reed	an excitation mechanism [see ‘transducer’] for aerophones that consists of one or more components of pliant material
relative pitch	a sound with a complex overtone structure that has no definite pitch but which, when heard in conjunction with other similar sounds, is perceived of as relatively higher or lower than them
resonator	the component of an instrument in which the energy generated by a vibrating object is amplified
ridge-nut	a ridge-like nut [see ‘nut’] over which a number of strings pass and that serves to mark one end of those string’s vibrational length; often notched to control the gapping of strings within and between courses
rim	see ‘counterhoop’
rotary valve	an 18^th century mechanical rotating valve design for brass instruments in which an instrument’s air column passes laterally through the cylindrical valve casing/s and with which an additional segment of tubing can be added to the basic length of an instrument’s air column [see Of Tubes, Slides, and Valves--How Brass Instruments Work]
saddle	a low ridge on the top face of a chordophone bridge with which the strings actually make contact; often notched to control the gapping of strings within and between courses
scraping	non-sonorous object is dragged over notched surface of sonorous object to sound it
side-blown	aerophone for which the airstream enters its air column through an opening on the sidewall of the instrument
single reed	(1) an excitation mechanism [see ‘transducer’] for aerophones that consists of the thinly shaved end of a single pliant cane or metal reed attached over an aperture in a mouthpiece that is in turn inserted into the end of a tube; (2) see ‘clarinet (1)’
slide	a mechanical device in the form of a telescoping slide with a U-bend that fits over two straight, parallel, stationary cylindrical sleeves; extending the slide adds additional length to the basic acoustical length of an instrument and brings a new combination of pitch possibilities into play [see ‘slide position’]
slide position	a point along the length of a telescoping slide at which a particular fundamental pitch and its harmonic partials can be produced
sliding nut	a tightly tied loop around the neck of a lute and a point on its string/s serves to articulate one end of the vibrational length of the string/s; this loop can be slid up and down the neck to set the precise spot at which the vibrational length of the string/s is located
slit drum	a struck idiophone usually made from a block of wood partially hollowed out through a slit cut in one of its faces (it is not a membranophone, as the word ‘drum’ in its name might suggest)
snare	a rope/s, wire/s or chain/s running across the taut membrane of a drum; the snare/s function as secondary beaters when the drum head they are placed against is set into vibration either directly of indirectly (by the sound wave energy from a struck head)
sound-table	see ‘soundboard’
soundboard	the acoustically sensitive surface of a resonator to which the vibrational energy of strings is passed via a bridge or by direct contact
spike lute	a chordophone the string carrier of which is bi-sectional, consisting of neck and resonator with the plane of strings running roughly parallel to that of the resonator soundboard - the base end of the neck penetrates the sidewalls of and passes through the resonator
stamping	sonorous object is sounded by thrusting it against a non-sonorous object
standing wave	a fast-cycling pressure wave contained in an aerophone’s cavity generated from and supported by the energy of an airstream that has passed through an excitation mechanism
Stölzel valve	an early 18th century mechanical piston valve design for brass instruments in which an instrument’s air column either enters or exits the bottom end of the cylindrical valve casing and with which an additional segment of tubing can be added to the basic length of an instrument’s air column [see Of Tubes, Slides, and Valves--How Brass Instruments Work]
stop	a rank of pipes (for organs) or choir of strings (for harpsichords), each pipe/string corresponding to a single key on the instrument’s keyboard, brought into action when the player pulls a stop knob
string carrier	the physical structure that supports the tensioned string/s of a chordophone
string course	number of strings played as one
string instrument	see ‘chordophone’
T - Z
tailpiece	a component of lutes to one end of which the strings are knotted and the other end of which is anchored to the bottom sidewall of the resonator; it serves to provide the resistance against which the instrument’s tuning mechanism works to adjust string tension
tapering bore	a general bore profile for aerophones in which the diameter of the bore gradually decreases over the entire length or nearly the entire length of an instrument
tension bridge	a component of a chordophone that is securely attached to an instrument’s soundboard and to which one end of each of the instrument’s strings is tied; it marks one end of the strings’ vibrational length, provides the necessary resistance to the application of tension to the strings at their other end for tuning purposes, and transmits the vibrational energy of the string/s to the resonator soundboard
tension collar/rim	a ring or flanged hoop/collar (sometimes referred to as a ‘rim’) that fits over the rigid frame of a framed membrane and that is part of a multi-component system used to apply evenly-distributed tension to a drumhead or a chordophone membrane sound table; the tension collar is connected to a resistance creating component of the system - a second tension collar lapped over another framed drumhead, an immobile counterhoop around the drum shell or chordophone resonator, or brackets anchored to the drum shell or chordophone resonator - with indirect lacing or threaded tension rods [see ‘indirect lacing’ and ‘tension rod’]
tension peg	a chordophone string tension-control device in the form of a rotatable shaft held vertical to the surface of the instrument body by the tension of a string; one end of string is threaded through a hole in the base of the shaft and out its side, secured with a knot around the peg shank; by rotating peg changes in string tension can be made
tension rod	component of tension collar fastening technique used for the attachment of framed membranes to drum shells or chordophone resonators; a metal rod at least one end of which is threaded and received by a nut of some design; the other end can also be threaded or in the shape of a bolt head or a hook
tension stub	a stub anchored in a chordophone’s string carrier against the side of which a tensioned string passes -- functions like a ‘nut’ to articulate one end of a string’s vibrational length
tie-down	a component of a chordophone in the form of a tightly tied loop around a string and a neck that bings the string firmly in contact with the neck and marks the end of the vibrational length of the string
timbre	the particular mix of partials (fundamental and overtones) in a sound gives rise to the perception of timbre or tone quality; the same pitch/frequency produced by different voices and instruments will each be of a different quality and will be identifiable from one another due to differences in their timbre
tone quality	see ‘timbre’
transducer	a device that transforms one form of energy into another form of energy (e.g., in aerophones a reed is used to transform the steady flow of airstream energy into the intermittent bursts of energy that generate an audible standing wave in the cavity of an instrument) [see ‘single reed,’ ‘double reed,’ ‘lip reed,’ ‘electromagnetic pickup,’ and ‘piezoelectric pickup’]
trough zither	the string carrier is a box- or bowl-like structure open at its top; strings run across the open cavity from one side of the carrier opening to the opposite side in a plane that is parallel to that of the opening
trumpet	(1) a generic term for any ‘lip reed’ aerophone; (2) English language name for the standard end-blown cylindrical-bore lip-reed aerophone of the Western music tradition made of brass, with or without valves
tube zither	a chordophone the string carrier of which is a length of hollow cylindrical tubing with strings anchored to its exterior walls near both its ends; the plane of the strings parallels that of the tube wall
tubular drum/shell	a membranophone shell with two openings; its exterior shape can take many forms [see ‘frame drum/shell’, ‘cylindrical drum/shell’, ‘barrel drum/shell’, ‘compound-conical drum/shell’, ‘hourglass drum/shell’, ‘conical drum/shell’, ‘bulging-conical drum/shell’, ‘goblet drum/shell’, ‘pedestal drum/shell’, ‘cylindrical-conical drum/shell’]
tuning block	see ‘pegblock’
tuning machine	see ‘machine head’
tuning peg	a chordophone string tension-control device that has at its core a rotatable shaft around which the end of a string can be wound: see ‘bushing peg’; ‘friction peg’; ‘machine head’, ‘tension peg’
tuning pin	see ‘friction pin’
tuning ring	a component of a chordophone to which one end of a string is attached; by sliding the ring up or down the neck of the instrument the tension of the string can be increased or decreased, thus changing its pitch
unframed membrane	a drumhead that has an un-reinforced edge and that must be attached to its drum shell with glue, tacks, or direct lacing
valve	a mechanical device engineered into brass instruments that allows for the rapid addition of segments of tubing to an instrument’s basic tube length; with each new length of tubing a different combination of pitches become available to the performer [see ‘piston valve’ and ‘rotary valve’]
vessel drum/shell	a membranophone shell with a single opening; its exterior shape can vary from nearly globular to pot-like, kettle-like, bowl-like, or vase-like
vibrational length	the actual portion of a string’s full length that is acoustically active
wind instrument	see ‘aerophone’, ‘woodwind’, and ‘brass’
woodwind	an umbrella label of the Western music tradition that subsumes a wide variety of edge, single-reed, and double-reed aerophones; the French horn [see ‘horn (2)’], a lip-reed aerophone, is sometimes included under this term
xylophone	(1) generic term for struck idiophones with solid oblong keys made of wood (‘xylon’ means ‘wood’ in Greek); (2) English language name for the standard wooden-key struck idiophone of the Western music tradition
yoke lute	a chordophone the string carrier of which is bi-sectional, consisting of a neck and a resonator, with the plane of strings running roughly parallel to that of the resonator soundboard - the base ends of two more-or-less parallel necks penetrate the resonator sidewall, their distal ends connected by a yoke; also referred to as a ‘lyre’ [see ’lyre (1)’]
zither	a generic term for chordophones with a uni-sectional string carrier over which strings are stretched

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