The generating force is any exchange of energy that results in some thing vibrating in such a way it can generate sound. These are generally forces, movement, and actions.

All classes are anything compressible such as gasses with the exception of 1.4 which is for minimally compressible liquids such as water.

Such as the wind directed into a wind instrument, controlled and the wind typically enters into an object using smooth laminar flow.

The primary wind force used to make wind instruments sound, this occurs when breath or other low pressure wind is funneled into an instrument. This is categorized by a low difference in pressure between the wind force and the air pressure in environment. Principle to most wind instruments, bagpipes, tabletop organs, most pipe organ pipes,

Such as is present on large organs, important distinction from breath pressure because of how much more psi this air can generate with significant difference between environmental pressure levels. Open air may produce sound like a air compressor. May result is forced vibrations on the object it is in interaction with, frequently produces shrill or uncontrolled tones. Very difficult to produce by breath pressure but possible on very narrow diameter wind instruments. May later be considered a form of regulation.

Sudden air burst that generates a sound such as the force used on stomping tubes and thongophones, related to the force that amplifies instruments such as marimbas which is considered a from of resonation.

Sound generating force does not make contact with the object it is enacted upon. Examples include clapping tubes.

Sound generating force does make contact with the object it is enacted upon, this entails an element of a striking force as well, which contributes to the initial sound generated at the start of the envelope. The effect stuck force is generally considered damped as it resonates the body of the instrument while the plosive force resonates any enclosed space. This class may need to be resolved.

Sound is generated with a plosive suction like that of popper tubes. This class may require physical contact.

When an object is effected by an oscillating wind force that typically causes torsional vibrations. Force is generally enacted around a sound generating material, and not funneled into as is seen with directional wind.

Like that found with most natural occurring wind that activates such things as a aeolian harp or when breath is funneled not into an instrument but across it such as with a lesiba. For wind entering an instrument see directed wind.

When there is a strong vortex shredding force involved, producing a more violent and erratic vibration pattern. The distinction between this and the above category is that the exciting force is sufficient to produce turbulence in the sound generating process that interrupts smooth consistent vibrations. Examples would be something like a fan, bull roarer, or an airplane flying. May later be classed as a form of regulation.

More technically fluids and gasses that behave as non-compressible (though they technically are compressible to a degree), this is the class for water and any instruments that use it such as all Hydraulophones.

For when liquids are forced into a system, typically under laminar flow.

When liquids are around a system.

Controversial concept, as I would find no certain evidence its even possible with non-compressible liquids such as water.

Oscillating Wind or Liquid forces that cause further sound generation, this may later be moved to Category 4- Sound Modification.

Such things as a rosined bow, the friction is primarily from the stickiness of the rosin and the friction force is consistent enough to generate pure tone like sounds that are dominated by the acoustic properties of the material being bowed and not dominated by the action of the bow damping the vibration.

Like the common action of bowing a string instrument, activating the strings in a transverse mode.

Like the bowing of the Long String Instrument, The cristal baschet, or Bart Hopkin's Pluffers. This action differs in the way that the material is interacted with.

When a material chatters against another due to the force of friction sliding against an object combined with a downward force against the object.

Like that seen when a lamell is slid perpendicular to another surface. Like the action of a chatter tool or nails on a chalkboard. Typically the material vibrating is struck against a smooth secondary material, opposite of the typical friction effect where the non vibrating material is slid against a stationary vibrating one. Directionality of the tip of the lamell is essential as it must be at or near a perpendicular angle for this force to act on the lamell.

For example bowing using corrugated rods or a corrugated wheel, friction is rapid and repetitive, but not continuous in the same way as listed above in A2.1. Rapidness is too frequent to allow decay patterns as would be seen by plucking. Does not apply to corrugated vibrational modes which are listed below, where the corrugation frequency determines pitch, but instead to the rapid repetition of a corrugated surface and its ability to agitate another sound generating object such as a string, with that sound generating object being the determiner of pitch. If the primary sound generating object is corrugation it belongs in Category B.

Generally quite, like the sound of rubbing ones hand on a bass drum, smooth non resistant friction that generates a muted sound.

Like the above example, where the active force of the friction does not substantially dampen the resulting vibrations

When the force of friction also dampens the ability of materials to vibrate, such as rubbing with a cloth or the shuffling of blankets. Generally a very quite form of noise generation.

When two or more separate objects make contact with force behind it in a way that causes any of them to resonate.

Object is struck in an overt way most commonly from a perpendicular direction to the surface. Only the striking object and not the object being struck is in motion (or vice versa).

A direct and clean strike that does not interfere with the vibration of the object being struck. In need of clarification on the name.

A direct strike where the object used to strike is allowed to bounce back from the force and repeat the action in a way that repeats more rapidly in succession, these strikes are rapid enough to interfere with existing resonation of the object.

When a direct strike is made and the striking object is held against the struck object causing a damping effect. Damping is substantial enough to affect the sound of the resonating object.

When the resonating object and the striking force are both in motion. May be done with two objects both in motion or many more objects in motion like that found in shakers.

Like that found on a flexitone or rattle drums where a directed beater cleanly strikes the object while they are both in motion.

Like that found in shakers and maracas where there are many objects in motion striking against one another. Classified by the more chaotic granular sound generated from many objects in motion.

Like a lotto spinner, these generate a granular sound through a spun action but is generally more consistent in the granular sound because of the smooth spinning action.

When a force is generated as a tension and then released, this is unlike striking in that the force is in the reverse direction, striking abruptly deforms a object at rest and plucking holds an object under tension that is abruptly released to generate the vibrating force.

When a plucked material is overtly warped and released, and the material maintains a smooth oscillating transition of state between the two states in a repeatable way.

When the deformation force is released there is a sudden and abrupt state change that lacks a smooth transition and may vibrate in an unstable way that is not repeatable. Examples include the popping of a lid such as a Snapple lid.

Difficult to categorize, may be striking or plucking or between the two, when a material is deformed in rapid motion as the striking frequency itself determines the pitch. Such as seen in klaxons. Categorized by the repetition of force that is consistent and rapid enough to generate frequency, and also rapid enough to interfere with vibrations occurring normally in the material effected.

Rapid production of magnetic force generates specific pitch frequencies that coincide with the frequency of the force. Requires a magnetic material. Often electroacoustic forces such as the sounds generated by stepper motors.

Like that of a knaxon or sirens. Typically generated by spinning. May later be combined with magnetic force.

Rapid temperature change can cause materials to vibrate, may later include phase change of materials such as the cracking of ice when placed into a drink or the cracking of glass when heated too quickly. May be moved as many of these concepts require the increase of tension until something brakes.

Energy (ion) exchange between plasma and various materials can generate sound. Mostly present with conductive materials such as metals, may be in some part carried over air, but the exciting force must be an ion exchange. This is the class that all plasmaphones fall under.

Different then plosive force, but somewhat similar.

An explosive exciting force is generated by exceeding the speed of sound in air. The cracking of a whip or the firing of a gun are examples.

Rapid release of gas or pressure differentials in a chaotic manner examples include pop rocks and cherry bombs.

The material that the generating force is enacted upon. These are materials that are capable of producing vibrations in the form of sound.
This section is most like the things that Hornbostel and Sachs classify in Systematik.

Mounted in center of the object typically at a position that is the node of the fundamental vibration. Objects in this class do not typically have separate longitudinal and lateral vibration patterns.

Circular objects with the mounting at the very center where the fundamental node is located. Object is generally flat and vibrates at the rim with most of the body of the shape vibrating.

Object is cup or bell shaped and mounted in the center, vibrates primarily at the rim. Shape is enclosed enough to form a detectable chamber.

Complex shape that is mounted in the relative center, has inconsistent geometry. Does not form a shape that has an enclosed chamber, examples could include the triangle. Difficult to classify because their needs to be maintained as having longitudinal and lateral vibration patterns as the same, which entails some geometric consistency across the object.

Not typically mounted at the very end of the object, but instead at one of the harmonic nodes that are produced when the material is vibrating.

Considered separate from lamells because the material is allowed to freely vibrate as the mounting is ideally at a node and not permanently attached. If method of mounting is at the end and causes the material to be unable to vibrate freely, and instead acts to firmly mount the material, it is a lamell. Proposed sublasses are likely to be changed later.

Typically found on bar shaped objects and mounted on both ends at the same node location of either end.

Like that of bar percussion instruments. Requires the object to have different lateral and longitudinal vibration patterns.

This is the category when the object being struck has a chamber to it such as a cylinder or a vessel and that chamber is resonate in such as way that the internal resonance activates along with the free body vibrations, in a manner that cannot separate the two. This is only applicable when both are present at the same time, caused by one sound generating force and cannot be separated. Examples are self tuned cylindrical wind chimes. May later be moved to being a Modifier.

Any material that is mounted on both ends while the material is also forced under tension between those two ends. Notable in that the two ends of the object are unable to freely vibrate while the center can.

Much like the metal string used for most orchestral string instruments. Though nylon and cat gut strings are somewhat elastic they should not be considered elastic as they are tuned to set pitches in such a manner elasticity is minimized and not a feature of the way they generate sound.

Again the most common form of strings includes any string where transverse and lateral vibration are the same.

Like those used on the Morin Khuur, all string that have a distinct width to height difference. These are any strings where transverse and lateral vibration are different.

Most string are taken for granted that they maintain the same width and height across their length, this is the class where strings have changing perimeters across their length.

This class may later be part of D where the degree of elasticity is taken into account as a way of pitch modification. For now it is the distinction where a string is elastic to the degree where any plucking, striking or, bowing causes the string to change in pitch and where consistent tuning is not fully possible on the string. Another feature is that linear tension is unequal across the length of the string because of elasticity and tension is locally altered by the act of interacting with the string. Examples include rubber bands and elastic cords being used as strings. Subclasses are the same as for non elastic strings.

Any string that is unable to be temporarily bent without the material holding its form, more akin to the transition to being rods that are mounted at both ends. These have a number of unique behavioral properties.

Any material that is linear in shape and mounted only on one end.

Like the tongues of a Kalimba and music box, toy piano, the rods of the Euphone, and the glass rods of a Cristal Baschet.

Typically not enclosed or mounted into a reed plate, like that of a Kalimba or the bowed rods of a Euphone. This category is also where a thunder sheet is classified.

Reed is contained within an enclosure which limits interaction with the lamella such as a Music box or Toy Piano.

Tongue is sheltered though the use of a rail or plate around the lateral edges of the tongue, like the reed plate of the Jaw harp. The plate must be able to limit torsional and longitudinal vibrations.

Like those found in the many free reed instruments such as Mouth organs, harmonicas, reed organs, and accordions. The chamber around the free reed is such that it allows only directional interaction and transverse vibrations of the lamella and promotes forces such as airflow while inhibiting direct interaction.

Lamella structured in such a way that the primary form of vibration is through air, a design methodology that frequently inhibits the use of other forms of vibration by use of an enclosure like a reed plate, or mouthpiece. These lamella have a structure that they interact with via physical contact when activated on their transverse vibration. Often these are connected to a tube to aid in reinforcing the pitch output and to allow for positive reinforcement to increase the sound volume.

Common to wind cap woodwind instruments, where the reed is the lamella and it vibrates against an enclosure that ends vibration of the reed on one side, this enclosure allows for the lamell to vibrate under wind pressure.

These are the reeds familiar with woodwind instruments, where the reed is the lamella and it vibrates against an enclosure that touches the limiting the free vibration of the reed on one side and also has a regulating material such as lips that can provide changing parameters of pressure and location to regulate the vibrational mode of the reed. This regulating agent is such that it does not substantially dampen the vibration of the reed.

Mouthpiece reeds that are damped as to limit the vibration of the reed. The three above subclasses may later be moved to regulation.

These are lemella that are made of a non rigid material that readily deforms. This is the equivalent of the string that is mounted only on one side, while the other side is left free and the string lacks mechanical tension. Examples include ribbon reeds where the wind action causes drag and vibration of the lamella and also whips. May later be expanded to make distinctions between circular flexible lamella and ribbon shaped flexible lamella.

Any two flat edges that are open and close to vibrate when wind pressure is applied to them. Typically the two sides are rectangular or trapezoidal in shape and are mounted on three sides with only one open side, sound is generated as the two edge sides open and close. This classification is for double reeds.

Reeds that have no form or regulation or inhibition to their sound output by the use of physical contact. Typical of windcap reeds.

When the two sides of the reed are rigid and the playing method causes a consistent opening and closing of the reed without substantial dampening, regulated by a material such as lips that is in contact with the lower section of the reed. These reeds have their sound output regulated by changing pressure and location of contact, but do not have their sound output substantially damped.

When the two sides of the reed are smashed together leading to a muted sound quality due to the ends being dampened. Characteristic of reed instruments such as the Aulos, Duduk and Hichiriki.

In need of a better name, proper reeds are forced to close, while Invert reeds are forced to open. The buzzing of lips is in this category as well as buzzing grass blades against one another and binder reeds.

Many Invert Reeds are made of non rigid materials such as lips or even fully malleable materials like putty.

Like the use of closed lips with wind pressure, Blowing raspberries and all brass instruments. Farting with hands, and elbows, Possibly also farts*. I am left unsure if this class should be unique all of its own, as yes lips are invert reeds and a non rigid material but they do have an ambiguous relationship to non body part materials such as membranes and the action of making them able to be warped can be considered a from of regulation. *farts may be considered a kind of aperture dilatation which would warrant its own subclass. I will wait to see if other examples develop before seeking a unique subclass.

Examples include the membrane clarinets where a membrane that is contained in a windcap is forced open by wind pressure. in this class membranes are forced against another surface and in a closed non vibrating state that is forced open. Generally these membranes are non rigid but also not freely warpable and are under continuous tension.

Such as farting with putty.

All reeds that are closed and go to a forced open state that are not lips. Examples include the rigid binder clips when blown into them the edges vibrate. Called retreating reeds by Jeremy Montagu and first described by Henry Balfour but never formally published and added to Hornbostel and Sachs Systematik. Similar subclasses proposed as for with other reeds, all of which may be moved to modifiers as a form of regulation.

A free elastic membrane that must always be at least partially enclosed with an edge. Like strings must also be under tension. Generally made from an elastic material. This is the principle class for drums.

A free rigid membrane that must always be at least partially enclosed with an edge. This is like the cajon.

Sound is generated by a force enacted against a hole in a shape like that of wind over the voicing of a flute. Objects of this type require to have some sort of internal chamber. The internal chamber shapes on this class are likely redundant and will later be moved to the resonator section.

Object with hole it is a cavity that is globular.

The hole does not lead into a larger shape and has no substantial depth as to be a chamber shape of its own, such as seen on disk sirens. All holes have some degree of internal volume but making the hole very short provides no audible pitch generated from the hole itself when in use by something like a siren which uses corrugation to generate sound, the pitch of the hole becomes secondary to the rapid sound generation of repeating holes.

When the object that a force is enacted upon is corrugated in such a manner that it allows for consistent repetition of that force and those repetitions produce a pitch relative to the amount of repetitions per unit of time. This is a unique phenomena as the repetitions determine pitch and not some other factor. Uniquely sound made from corrugated systems tend to be able to play subharmonic series as excessive force is applied can causes repetitions to be skipped, which can be a determining factor.

Corrugated tubes are used for applications where air or any fluid is forced to oscillate inside of a tube generating a pitch. Corrugated rods and tubes are used in a similar manner to other corrugated surfaces and can be rubbed and chattered against to generate consistent pitch.

Repetitions primarily made by parallel lines of corrugation includes such things as lenticular plastics and gears. These can be flat or folded into a cylinder which takes advantage of he directional nature of the ridges. This is the primary sound generating material on the savarts wheel.

Corrugations occur as grids with various geometries, found on such things as a fresnel lens materials, these surfaces can generate tones in multiple directions with pitch shifts that coincide with the frequency of corrugation in each direction, capable of unusual arpeggiation due to changing direction of the applied force.

A corrugated disk can be spun and the edge corrugations, which are often shaped like waveforms, will repeat and generate pitch. Common to the technique used on some electromachanical organs where the disks are used to oscillate an electrical current. Disks of this type are common on Hydraulophones, Disk Organs (Harmon Organ), and Sirens.

Like the surface of sandpaper, allows for complex noise to be generated when certain forces are applied, does not generate a consistent pitch, but instead a consistent pitch noise range. Typically generate the same sound profile despite direction of interaction.

These are things that are not the primary source of the sound, but resonate and amplify that sound. This includes Resonators and Amplifiers. Many of these translate vibrations in a material into air waves. Resonate can both mean reverberates the sound as well as being able to determine such things as pitch and timbre. Things that only selectively amplify such as sympathetic strings are classified under modifiers.

Typical of free rigid vibrating materials where there is no external form of amplification or sound resonator.

Like the resonator tubes of a marimba or the tube of a wind instrument. Dependent on the clause that the shape is capable of generating linear standing waves. Objects that produce multidirectional standing waves should be considered helmholm resonators.

Such that the walls of the material are able to reverberate sound waves

Where the walls of the martial are made of an elastic or malleable material such as the mouth.

These are typically attached at one point in the center to a conductive material that transfers the sound waves into the large rigid cone where it is translated to air movement. The cone shape generated may or may not be symmetrical. This is exclusive to cones that reverberate a broad range of frequencies.

Drumheads, Like on a banjo, not to be confused by drumheads that are the primary material that generates vibrations when excited. This class is taking existing vibrations that are produced and translating them to air waves.

Soundboards like that of a guitar, can also be expressed as a soundboard of a piano or harpsichord or even soundboards like those found on some glockenspiels.

Like the woodblock attached to a Kalimba act to translate vibrations into air more efficiently than the primary vibrating force. If they act to substantially dampen frequencies than the solid mass is classified as a pitch modifier instead (class E).

Changes in one of these values will change the pitch produced by the resonator, amplifier, or the object that force is enacted upon. This can occur both as a state change on a single object (change in string length, changing the tension on a drum head, opening and closing of holes on a tube) or by having multiples of an object (bar percussion of various sizes, tubes of various lengths, various sizes of membranes on drums).

Pitch is altered by a change in mass (thickness) of the object. examples include making strings of various gauges having different pitches, making membranes and lamells thicker.

For example longitudinal waves in rods have different pitches depending on the density of the material.

Such things as gongs and bar percussion increase size of bars and multiple variables such as length, depth, and width all increase in tandem.

Change of any linear length like that of a string, a bar, a hollow cylinder or cone, without effecting their width.

Increasing or decreasing tension on a string or a membrane (stretching)

Helmholtz Resonators (anything with Non Linear Standing Waves) require a change in internal volume to change pitch.

Stepper motors, corrugated sounds, and wind instruments have their pitch effected by speed. Various wind instruments are effected by pressure differences which can be represented by speed.

Changes in electrical resistance or voltage can change pitch in instruments that have their sounds amplified by electroacoustic means.

These are pitch specific objects that react to pitches produced by themselves vibrating at the same frequency or a relative harmonic of it. Only to be included when they are in physical contact with the sound generating object. If not attached to another object the sound generating force should be considered A1.5- Wind and Liquid Based Vibrations and the sound that generates the force of air vibrations should be considered a separate instance of sound generation.

Tuned strings that vibrate along with the main generated vibrations when the two pitches coincide.

Tuned lamella tongues that vibrate along with the main generated vibrations when the two pitches coincide.

Objects that are attached in such a way that the action of a vibrating mass is of a different frequency to their own vibration causing them to repeatedly tap against it. Requires some kind of physical contact to operate. This is a form of forced vibration rather than sympathetic vibration.

String bridge that utilizes the string tension to stand with high tension on one side and very low tension on the other, causing one foot of the bridge to buzz as the vibrations of the strings (vibrating the bridge) do not match the vibration of the resonator of the instrument causing the foot to chatter.

Selective sculpting of contact points on strings and lamellas that activates various harmonics due to the forced interaction of the two surfaces.

Small rigid tongues that are attached in such a way that the action of a vibrating mass is of a different frequency to their own vibration causing them to repeatedly tap against themselves or any other free masses.

A length of wire that is bent back against itself as to make tension against the vibrating mounting surface and because of its own vibration being delayed buzzes against that surface Similar to the Buzzing Bridge but is separate to the sound generating object in such a manner that it is indirectly attached.

Attached membrane that freely vibrates against itself when excited by existing standing waves, typically activated by air pressure changes in a chamber or tube.

Inconsistent pressure waves that interfere with the consistent oscillation of sound producing waves. Modifies the timbre of wind instruments and instruments that rely on vortex shredding. Also present inside of chambers when air streams are forced to cross over one another. In need of expansion.

When something is damped by the action of holding motionless tension against it. Opposite of a buzzing element. This is a proposed class for all damped forces listed above. The current classes will remain until there are further implications thought through of this feature.

Possible location for the action of crushing (damping) the various wind blown reeds (true reeds, membranes, invert reeds, and lamell reeds) as to alter their sound output as to reduce harmonics present and limit the various vibrational modes the reeds produce. Unsure if this should be considered a primary feature of the sound generating process or a modifier.

Objects that absorb many frequencies and only allow the reverberation of a very select few and dampen the rest, act as a sink that only allows selective pitches to remain.

Tuned solid mass that behaves as a lamell may act both to vibrate sympathetically and as a pitch filter.

The use of a regulating force, such as lips, to control the vribrational mode of the material that is generating sound. This force is such that it does not substantially dampen the vibration but instead alters the ability for specific harmonics or modes to occur in the material. Examples include playing harmonics on strings (the regulating force is touching the string at a harmonic point) or the control players lips give to many wind instruments such as brass instruments (invert reed control) and woodwinds where the lips regulate the ways that the reeds vibrate. I am unsure if this type of force should be considered primary to the sound generation or if it should be considered a sound modifier (much like damping listed above). This has the potential to expand into a very large subset of effects as many instruments involve themselves with various forms of regulation to play.

Such as the action of playing an overtone by gently touching a string to divide it into a harmonic division.

Such as the action of adjusting the lips and breath pressure on a brass instrument to produce an undertone series. Another example is increasing the speed but lowering the pressure when scraping a corrugated surface to cause the corrugations caught by the action to skip and generate a lower pitch.

In need of revision, this section if for when an sound is effected by the use of motion or proximity to another object.

There needs to be clarification with the needed location of classes for reeds-
Unmuted reeds and lamell (Windcap)- Reed vibrates without something regulating it, making them unable to overblow
Regulated Reeds- Reed is regulated by something like lips which allow it to vibrate in a more stable and controllable mode, allows for overblowing
Muted Reeds (damping)- Reed is crushed and muted by something like lips, the act of crushing the reed generated a characteristic muted timbre, inhibits overblowing.
Do these actions count as modifiers or parts of the primary sound generating process?