Abstract: An electronic material instrument includes a tone generator for synthesizing tones by using a number of time-division multiplexed (TDM) modules, an input unit for programming a connection configuration (tone synthesis algorithm) for the modules of each module pair, and a processing unit for converting the input program into control data for each module and transferring the control data to the tone generator. In one embodiment, each module pair is selectively operative in an addition mode, a phase mode or a ring modulation mode, independently of the modes selected for the other module pairs. It is thus possible to attain a tone synthesis desired by the user, and to make the best use of the capacity of the tone generator.

Abstract: A method and apparatus for controlling a keyboard operated device having a plurality of keys includes a plurality of sensors associated with each key. Each sensor detects a different one or more attribute of the nature of actuation of the key. Each detected attribute is used by selection circuitry to form a characteristic of the device's response to actuation of the key. The individual characteristics are combined to form a response to actuation of the key. The response may be an output signal or may be further processed internally by the device. In a preferred embodiment the invention is part of a musical synthesizer. One sensor is arranged to detect actuation of a key, while a second sensor is arranged to detect which finger actuates the key. The detection of actuation of a key is used to control the pitch of the resulting output. The detection of which finger actuates the key is used to control the timbre of the resulting output signal.

Abstract: A sensor arrangement for an automatic piano player apparatus is provided. The sensor arrangement includes a plurality of switches which are operatively associated with a rotatable shutter in the hammer system of the automatic piano player. When the hammer system is operated to strike a string of the piano, the cooperation between the rotatable shutter and the switches produces output information which includes the string-striking intensity information and the state of condition information of the damper that is normally in contact with the piano string. With this information, the various play techniques such as staccato, legato, continuous key-striking and the like may be reproduced with great fidelity by the automatic piano player apparatus.

Abstract: A musical tone control apparatus includes at least one grip device having the shape which can be held by player's hand. This grip device further includes plural push switches each having a piezoelectric element whose resistance is varied in response to depressing pressure applied thereto. Based on a combination of depressed push switches and its depressing pressures, an externally provided musical tone generating apparatus is controlled such that tone pitch, tone color, tone volume, touch response or the like of musical tone will be controlled. In addition, an angle detector for detecting a swing movement of a player's arm can be further provided. Thus, the detected swing movement of the player's arm can be additionally used for controlling the musical tone.

Abstract: A striker designed to strike or be swung for playing music is provided with a musical sound-initiating command signal-generating device including switching members. When the striker strikes or swings, the switching members perform a switching action which triggers the transmitting of a musical sound-initiating command signal from the musical sound-initiating command signal-generating device. A desired musical sound is produced by a musical sound producing unit in response to the musical sound-initiating command signal. A number of different timbres can be selectively used for a musical tone, by operating a timbre-selecting switch provided on the striker.

Abstract: A touch response device for an electronic musical instrument includes pressure detector for detecting initial-touch and after-touch of a key. The pressure detector means has two or more response stages that have different response characteristics to key pressure variation. An initial-touch-detector signal is produced when the pressure detecting means is in a first response stage among the response stages, and after-touch-detector signal is produced when the pressure detecting means is in a second response stage among the response stages. According to the invention, initial-touch signal and after-touch signal are generated by the use of one common operation-detector signal produced from the pressure detector means. As a result, the construction of the pressure detecting means is much simplified compared with a conventional touch-response device provided with two separate detectors, one of which detects initial-touch and another of which detects after-touch.

Abstract: In order to eliminate the disadvantages due to varieties of a string-striking speed (i.e., dynamic characteristic) of a hammer, a hammering operation control unit is applied to a piano accompanied with an automatic performance function which can reproduce a musical performance recording in advance. Based on a detected string-striking speed of the hammer which is driven by the reference drive value predetermined to each key, the hammering operation control unit computes a deviation from the target string-striking speed corresponding to the reference drive value as a compensation value. Then, the newest computed compensation value is stored in a memory device or medium such as a floppy disk by periodically renewing the stored compensation value. Based on the stored compensation value, the string-striking speed of the hammer is to be compensated.

Abstract: A keyboard assembly for forming a keyboard apparatus of an electronic musical instrument, including a combination of at least two key units each having a plurality of key members and an elongated bracket portion connecting the key members together, a frame structure to which the key units are assembled together in such a manner that each of the individual key members of the key units is allowed to rock independently of each other about an axis fixed with respect to the frame structure and parallel with the bracket portion of each key unit, and plural combinations of a concavity formed in the bracket portion of one of the key units and a projection formed in the bracket portion of the other of the key units and received in the concavity for establishing a first predetermined positional relationship between each of the key units before the key units are assembled to the frame structure.

Abstract: An automatic player piano is implemented with an automatic player unit and a mechanical piano having a keyboard mounted on a key bed, and the automatic player unit has a controller operative to memorizing pieces of a key touch information respectively representative of grades of intensity assigned to the sounds in the recording mode of operation and retrieve the pieces of the key touch information in the playback mode of operation, a plurality of actuators provided in association with the keyboard and responsive to the pieces of the key touch information for causing the keys to move, and a sensor unit operative to detect key motions of the keys for producing the pieces of the key touch information in the recording mode of operation, wherein the sensor unit is provided between the keyboard and the key bed because the space therebetween is largely equal regardless of the model of the mechanical piano.

Abstract: In the construction of a sound bar musical instrument such as a marimba, at least some of the sound bars have sensors attached thereto. The sensors are electrically connected to an electronic sound generator unit for generation of musical tones as a function of the vibration of battered sound bars, thereby allowing free use of a mallet and enabling visual contact of the performer with the audience.

Abstract: A keyboard apparatus of an electronic musical instrument includes keys, mass members, and springs. Each key can pivot about a first pivot fulcrum. Each mass member can pivot about a second pivot fulcrum. Each spring supplies a biasing force to at least the corresponding mass member so that the mass member returns to an initial state. In this apparatus, each key has a point of application for pivoting the corresponding mass member in the same direction as a pivoting direction of each key when each key is depressed.

Abstract: A keyboard system for an electronic musical instrument of the keyboard type, such as a synthesizer, electronic piano, organ or controller keyboard. The keyboard includes an electromechanical key actuation and sensing element that in combination with electronic processing allows the performer to adjust both tactile and tone control parameters associated with keyboard touch response. The tactile response can be tuned over a broad range and is capable of simulating a light organ touch, heavier "piano key feel" or stiff percussive action. Since any of these features can be selected and adjusted while the performer is playing the keyboard, the keyboard system also has a desirable "real time" capability that does not interfere with musical performance.

Abstract: There is disclosed a keyboard structure incorporated in an electronic keyboard instrument the keyboard structure including; a plurality of key members each having a depressible front end portion and a rear end portion; a plurality of flexible connecting members each merged with the rear end portion of each key member; a retainer member merged with the flexible connecting members for retaining a circuit board which carries a plurality of key switches; and a plurality of coupling members each having a first element merged with the rear end portion of each key member and a second element merged with the retainer member, and the first element is snapped into the second element, so that major members are simultaneously formed by a molding, thereby enhancing the assembling efficiency.

Abstract: An electronic keyboard percussion instrument includes a hammer such as a mallet, a plurality of plates, striking detection devices, and a musical tone generating section. The plates respectively correspond to note names of musical tones to be produced and aligned parallel to each other. The striking detection devices are respectively mounted on lower surfaces of the plates to detect striking of the plate with the mallet and to generate a striking detection signal. The musical tone generating section generates a musical tone of the note name corresponding to the struck plate in response to the striking detection signal. The striking detecting section may include a pressure sensitive element in order to make the musical tone responsive to a force striking the plate.

Abstract: An integral music system for use in association with all chromatically scaled musical instruments comprising an improved graphic keyboard design utilized in various mechanical, electric and over-keyboard embodiments, and a cooperative improved hexaline scoring method utilizing octave-designating noteforms, and a cooperative improved graphic referencing method utilizing color, symbol and tactual coding means. The improved graphic keyboard design has essentially coextensive alternately arranged, uniformly narrowed and widened keys. The improved hexaline scoring method has one or more six-line staffs which respectively utilize eight distinct noteforms to provide an eight-octave compass for each staff. The improved graphic referencing method has code formats which correlate the lines and spaces of the improved scoring method with the keying means of the various instruments. The invention additionally comprehends manual and computer assisted methods for converting existing music into the improved scoring format.

Abstract: A musical keyboard having keys which carry metal spoilers that alter the resonance characteristics of tank circuits associated with the keys as the keys move toward and away from the inductance coils of the tank circuits. The tank circuits are connected sequentially to a frequency sensing circuit which develops indications of key positions by sensing the resonance frequency of each tank circuit.

Abstract: The present invention relates to an improved musical cube. The cube includes circuitry mounted within its cubical housing with the circuitry including three two-axis switches with each such switch having a central open position and two positions, one to either side of the central position, each side position of which closes a particular unique sub-circuit. The three switches are mounted in the housing in mutually perpendicular relation and the switches combine to control the operation of six sub-circuits. In the operation of the improved musical cube, a read-only memory and synthesizer device are incorporated into a circuit with the read-only memory being pre-programmed with a distinct musical sequence for each of the six sub-circuits.

Abstract: A portable modular music recording device which simply and unobtrusively attaches to a keyboard instrument for purposes of recording live musical performances; and an efficient music microcomputing system in which the captured musical data is digitized and further analyzed to determine note and note expression information when a key has been played. In the modular keyboard device, key and key expression data is captured by means of reflective couplers mounted in the keyboard device, and the information is transmitted to the processing unit. Microcomputer instructions refine the data to a format suitable for serial transmission via a computer-compatible link for ultimate scoring and recording.

Abstract: A new type of musical instrument and performance apparatus is disclosed and is used with the special performing art called "Instrument dance", "instrument exercise" or "instrument boxing" etc. The instrument comprises a floor keyboard, on which the performer can either dance and produce switching signals with his or her feet, hand or hand hammer in accordance with the intention of the performer. In addition, a similar wall keyboard is provided along with a multi-color system and an electronic organ circuit. The performer can play on the floor keyboard while at the same time adjusting with ease the tone, timbre, volume and color, to thereby achieve the multiple artistic effect of a single performer producing the shape, sound, light and color of the performance.

Abstract: A portable modular music recording device which simply and unobtrusively attaches to a keyboard instrument for purposes of recording live musical performances; and an efficient music microcomputing system in which the captured musical data is digitized and further analyzed to determine note and note expression information when a key has been played. In the modular keyboard device, key and key expression data is captured by means of photosensitive couplers mounted in the keyboard device, and the information is transmitted to the processing unit. Microcomputer instructions refine the data to a format suitable for serial transmission via a computer-compatible link for ultimate scoring and recording.

Abstract: A portable set of electronic drums includes individual drum units which are attached to different parts of a musician's body to provide maximum mobility for a stage performance. An impulse analyzer with each of the drum units processes the outputs of the drum units for transmission to a synthesizer which further processes and amplifies the resulting sound for application to a loudspeaker. A wire, radio transmitter or optical link may be employed to communicate the signals from the musician's body to a stationary synthesizer and loudspeaker. A percussion transducer in the musician's shoe may be employed to further increase the flexibility of the system. The output of the percussion transducer in the musician's shoe is combined with the outputs of the remaining drum units to create a total drum signal. In addition, the outputs of the shoe percussion transducer and the drum units may be employed to control the energization of optical emitters on the person of the musician.

Abstract: In an optical sensor for displacement speed/displacement of a movable element in a musical instrument, light emitted from a light-emitting element is guided to a sensor head through a transmission optical fiber and is further guided to a light-receiving element through a reception optical fiber. The sensor head is located at a position corresponding to a shutter movable in accordance with the movable element in the musical instrument. The shutter controls photocoupling and nonphotocoupling between the transmission and reception optical fibers. The sensor is of transmission or reflection type.

Abstract: A keyboard switch apparatus for an electronic musical instrument has first, second and third layers, and first and second switches. The second layer has elasticity and is separated from the first layer. The third layer has elasticity and is inserted between the first and second layers at a distance therefrom. The first switch consists of conductors respectively formed on opposite surfaces of the second and third layers. The second switch consists of conductors respectively formed on opposite surfaces of the first and third layers. The second and third layers are sequentially urged and deformed by an actuator interlocked with key depression. The first and second switches are sequentially closed. A time requred for closing the first switch is different from that for closing the second switch. The closure time difference corresponds to a key depression speed, which is used to generate a signal corresponding to the depression speed, and a musical tone signal corresponding to the depression speed.

Abstract: A membrane keyboard for e.g. a low cost electronic tone generator of the type affixed to the binding of a songbook is disclosed. The keyboard includes a base carrying a set of interdigital upwardly facing printed circuit contacts for each key. A membrane overlay is vacuum formed of a thin plastic sheet to define a horizontal row of playing keys, each key being formed as a plateau area, with a vertical depression spring rib separating each key. Each key includes an elastomeric foam pad affixed to its underside area which carries a conductive lower surface aligned with with the interdigital traces of the key. The conductive surface bridges the traces to complete an electrical circuit when the membrane is depressed downwardly from its top surface.

Abstract: In an electronic keyboard musical instrument with a portamento or glissando play function, a touch response detector is arranged to detect a key touch response such as a depression speed or pressure of a key depressed on a keyboard. A musical tone generating device with a portamento or glissando play function is arranged to change a portamento or glissando time in response to the touch response of the depressed key.

Abstract: A touch sensitive electronic musical or sound generating instrument is disclosed. The invention utilizes digital techniques to sense how hard any one of a plurality of push buttons on a keyboard is depressed or actuated. The instrument generates a desired or particular sound (such as a musical note) at a desired parameter such as volume, corresponding to how hard a specific button was depressed.

Abstract: An electronic musical instrument has a keyboard, a key depression speed detector and a glide pattern generator. When any key of the keyboard is depressed, the key depression speed detector detects the speed of depressing the key and produces a signal representing this speed. In accordance with this signal the glide pattern generator changes a reference glide pattern to a new pattern. The instrument generates a musical tone having the glide effect determined by the new glide pattern.

Abstract: A percussive action silent electronic keyboard provides electrical input signals for electronic music synthesis equipment. The keyboard includes a housing, and a keyboard array of a plurality of depressable pivoted playing keys adjacently arranged as a musical keyboard. Each key communicates with a pivoted silent hammer in a cam and follower arrangement. A stop is provided for stopping the momentum of each silent hammer which is caused to move about its pivot by following a camming surface of its corresponding key resulting from depressing of the key during playing action. An electrical switch provided for each key, and the switch is responsive to the playing action of the key for generating and supplying electrical signals indicative of the action to the electronic music synthesis equipment with which said keyboard may be used to generate music.

Abstract: A keyboard switch apparatus for an electronic musical instrument has first and second switches each constituted by stationary and movable contacts. The stationary contacts of the first and second switches are formed adjacent to each other on a single board. The movable contacts of the first and second switches are mounted on a single flexible member arranged above the single board and are normally spaced apart from the stationary contacts at positions opposite thereto. The flexible member and the movable contacts of the first and second switches are integrally formed to have a uniform cross-sectional shape along one direction. The flexible member is deformed in response to the depression of a key. The stationary contacts corresponding to the movable contacts of the first and second switches are closed with a time difference according to a speed of key depression.

Abstract: A keyboard-operated tone-producing apparatus having, in combination, keyboard means the keys of which are mounted for downward depression to effect tone production in the apparatus; electronic digital signal processor means; tone-generating means; pressure sensing means responsive to key depression to produce signals corresponding thereto for application to the signal processor means to produce corresponding digital signals applied to generate tones from the tone-generating means; means for causing the pressure sensing means to provide the same signal reference, upon key depression, irrespective of the point of pressure along the path of longitudinal sliding of the key; and means controlled in response to the last-named means and cooperative with the signal processor means as it controls the tone-generating means to produce one or all of variable range bending of the tone, center compensation for differing player techniques of key depression, and second striking of the key while depressed for second tone gene

Abstract: The present disclosure describes circuit variants for reducing electromagnetic interference from saturable core keyboards to acceptable levels. The invention finds particular application in conjunction with capacitive-discharge scan techniques used in such keyboards. In order to attenuate the external field resulting from such techniques, a circuit is taught which effectively disconnects the scan line array from the capacitor charging circuit during the time between scans. A second variant, when added to the first, further reduces interference by disconnecting the entire scan circuit from the supply potential during the scan time thereby eliminating steady-state currents and turnoff oscillatory transients.

Abstract: A sound producing device producing different notes when rotated. Three orthagonally mounted gravity switches produce signals corresponding to their orientation to a reference. A multiplexer or programmable counter coupled to the switches selects one output line for each combination of states of the switches. Each output is passed through different values of resistance so that unique frequencies result. The output of the multiplexer is coupled through an oscillator to a speaker and a tone corresponding to the frequency of the output selected is produced. Multivibrators are coupled to the switches and to the oscillator to shut off the production of sound when the device has been left at rest for a certain time period.

Abstract: The touch dynamics of the operation of keys of an electronic musical instrument are determined through the use of pressure sensitive transducers associated with the keys, the transducers each including a magnetic field responsive semiconductor device and providing signals which are analyzed to determine their variation in magnitude as a function of time. Additionally, after a pre-selected time period, if a key remains operated and the pressure exerted thereon is varied, the output voltage of the key associated transducer will be further analyzed to determine if the player is calling for the reproduction of a secondary effect.

Abstract: Apparatus and method for the monitoring of the manipulation of the keys of an instrument comprises monitoring apparatus which takes the form of a pressure sensing device, associated with each key, that can be fabricated in a configuration compatible with the instrument. According to one embodiment, the pressure sensing devices can be arranged so that the monitoring apparatus can be positioned on a balance rail of a piano keyboard. In this embodiment, the monitoring configuration can be fabricated and conveniently retrofitted to a standard keyboard. The pressure sensing device comprises a resistive element, a conducting element, and a force transducer ink layer separating the resistive and conducting elements. The resistance of the resistive element is monitored and when pressure is applied to the pressure sensing device, a change in resistance can be measured. Because the resistance is a function of pressure, the amount of pressure used to activate the key can be determined.

Abstract: A data input apparatus comprises an operation panel; a plurality of input keys arranged on the operation panel; and a fine adjusting bar arranged on the operation panel; and a data generator coupled to the input keys and to the fine adjusting bar. Each of the input keys designates a coarse selection of an input instruction, respectively, from among a plurality of input instructions such as musical note pitches and durations. The fine adjusting bar designates a fine adjustment for and in common to the respective selected input instructions designated by the input keys. The data generator generates data bearing information formed by the selected input instruction and the fine adjustment. Thus the data input apparatus composes musical performance data for automatic performance by musical tones with adjusted note pitches, note durations, and other note characters.

Abstract: A tone generating glove includes switches and a tone generating circuit. The switches are connected to the tone generating circuit, and both the switches and the tone generating circuit are mounted in the glove. The tone generating circuit produces a tone or tones in response to the actuation of one or more of the switches. Preferably, a switch is positioned at each finger joint of the glove. The tone generating glove may also include a transmitter for transmitting the tone or tones that are produced to an AM or FM receiver. Each switch may include a flexible insulating sheet having upper and lower surfaces and an opening formed through its thickness. Flexible and electrically conductive first and second outer laminas are respectively attached to the upper and lower surfaces of the insulating sheet. They are positioned on the surfaces of the insulating sheet so as to bridge the opening in it.

Abstract: A keyboard system in a keyboard controlled musical instrument includes a pair of spaced apart electrode members and a pickup movable in the space intermediate the electrode members. Respective voltages are impressed on the electrodes to establish an electric field therebetween and the voltage impressed on the movable pickup is a function of its position relative to the two electrodes. The pickup is actuated by the playing key which contacts a resilient, yieldable stop. The force with which the playing key is depressed is measured by sensing when the key is fully depressed, initiating a count at that point and counting a predetermined period. At the end of the predetermined period the voltage on the pickup is detected which gives an indication of the amount of overtravel of the key beyond its normal depressed position. This detected voltage is used to alter the quality of the tones produced by the musical instrument.

Abstract: A calibration system for the keyboard of an electronic musical instrument. Compression of the key causes an output signal to be generated which varies in accordance with the amount of key depression. When the key is depressed to a nominally fully depressed position, the system stores an offset value relating to the difference between the actual output signal at this point and an expected reference output signal which would occur if the keyboard were perfectly adjusted from a mechanical standpoint. The offset value is stored in the memory and added to the key output signal during the normal operate mode of the instrument so that the output signal is adjusted in accordance with the offset value stored during the calibrate mode.

Abstract: An input device for an electronic musical instrument, has blown air apertures and suction air apertures alternately disposed on the front face of its main body. This input device also has elastic members provided within the blown air apertures and suction air apertures, in such a way as to be deformed by the force of the air caused to flow through said blown air apertures and suction air apertures. The input device also has magnets or pressure members serving as operation members, which magnets or pressure members are each displaced by an elastic member, and a plurality of musical tone input switches are driven by the displacement of the magnets or pressure members.

Abstract: A touch control apparatus for an electronic keyboard instrument, comprises a sensor having: an elongated insulating sheet having a set of conductive pattern films on a surface thereof, the elongated insulating sheet being folded and the set of conductive pattern films being formed to be spaced apart from each other; and a pressure-sensitive element sandwiched in a space defined by the folded elongated insulating sheet to be in contact with the conductive pattern films. The pressure sensitive element is deformed when a key of the instrument is depressed to deliver an electrical output through the conductive films representing the magnitude of the key depression. The apparatus is superior in easiness of handling the sensor and of assembling the apparatus.

Abstract: There is disclosed a key which is particularly adapted for use in a musical keyboard. The key includes a top pivotable member which acts as a key surface and which is pivoted to move with respect to a reference plane. The key contains on a bottom surface a magnetic field effecting member. Located beneath the key on the reference plane is a rigid board containing a planar coil configuration. As the hinge member is moved towards the rigid board, the member affects the magnetic field of the planar coil configuration to vary the inductance as well as the magnetic coupling in other arrangements. A plurality of such keys are employed as the keys in a musical keyboard and are associated with frequency determining circuits such as oscillators to provide output frequencies necessary for the control of music.

Abstract: A keyboard for an electronic music instrument is made to have a "piano key feel" by bracketing an end of each key with the legs of a weighted A-shaped action arm which pivots about a single point and actuates a leaf spring switch.

Abstract: A keyboard system for an electronic musical instrument of the keyboard type, such as an electronic organ, synthesizer or electronic piano. The keyboard is responsive to the velocity with which the key is depressed and controls the tone generation circuitry to produce tones of higher amplitudes for higher key depression velocities. The keyboard also includes an aftertouch control whereby further depression of the key past its normal limit against a compressible medium, such as a foam rubber or felt washer, alters the quality of the tone produced. For example, the aftertouch control could be used to vary vibrato, change pitch, change decay, and the like. A pickup for each key is positioned in an electric field set up between two electrodes, and the voltage impressed on the pickup will change depending on the position of the pickup within the field as determined by the amount of depression of the key.

Abstract: The touch dynamics of the operation of keys of an electronic musical instrument are determined through the use of pressure sensitive transducers associated with the keys, the transducers providing signals which are analyzed to determine their variation in magnitude as a function of time. Additionally, after a preselected time period, if a key remains operated and the pressure exerted thereon is varied, the output voltage of the key associated transducer will be further analyzed to determine if the player is calling for the reproduction of a secondary effect.

Abstract: The present invention provides a touch response apparatus for an electronic keyboard instrument wherein, in controlling a touch response state by detecting a key depression speed in the electronic keyboard instrument, the touch response states of keys are detected by detection means smaller in number than the keys, and the difference of detection outputs attributed to the different mounting positions of the contacts of a white key and a black key is also compensated.

Abstract: A new, performer played, real time, multitonal, multimbral musical instrument consists of speed and force sensitive keys in which time domain multiplexing is used to find and associate one and only one tone generator, not otherwise busy, with any key that is depressed. The sound generator disclosed can provide very realistic simulations of the flute, oboe, trumpet, French horn, trombone through the provision of various types of modulations in amplitude and frequency of the various partials, as is characteristic of each instrument simulated, and filtered noise. Glissandi are provided from one note to another and are controlled from the pair of keys involved by the relative pressure with which they are depressed. For the nonpercussive tonalities, the speed with which a key is depressed, which is determined by differentiating the force, may be used to cause the attack transient to behave in a manner very characteristic of the instrument being simulated.

Abstract: A keyboard for a musical instrument having a plurality of elongated keys with each key having a rearwardly extending actuating arm. The arm has an upper and a lower nonresilient switch actuator for actuating a respective first and second keyboard switch with each switch having a substrate with at least one fixed contact. A deformable membrane has coupled thereto a movable contact which is adapted for movement into and out of electrical connection with the fixed contact. The first and second switches are positioned so that the lower actuator normally maintains closed the first switch and when the key is actuated the first switch opens and the upper actuator closes the second switch. The deformable membrane is formed of Poron cellular urethane which distributes and absorbs the actuation force and springs back to its undeformed shape when not actuated.

Abstract: A keyboard-operated tone-producing apparatus having, in combination, keyboard means the keys of which are mounted for downward depression to effect tone production in the apparatus and for longitudinal sliding to alter or bend the tone; electronic digital signal processor means; tone-generating means; pressure sensing means responsive to key depression to produce signals corresponding thereto for application to the signal processor means to produce corresponding digital signals applied to generate tones from the tone-generating means; means for causing the pressure sensing means to provide the same signal reference, upon key depression, irrespective of the point of pressure along the path of longitudinal sliding of the key; and means controlled in response to the last-named means and cooperative with the signal processor means as it controls the tone-generating means to produce one or all of variable range bending of the tone, center compensation for differing player techniques of key depression, and second s

Abstract: A bounceless switch apparatus having a junction resistance which varies inversely with the pressure applied normally thereto which includes a first conductor member, a pressure-sensitive layer including a semiconducting material covering the first conductor member in intimate electrically conducting contact therewith and a second conductor member positioned in nonelectrically conducting relationship to the pressure-sensitive layer. The pressure-sensitive layer has a first surface with a multiplicity of microprotrusions of the semiconducting material which provide a multiplicity of surface contact locations. As the normally open switch is closed in response to a pressing force applied to urge the second conductor member and the first surface together, the physical contact between the microprotrusions and the second conductor increases thereby variably increasing conduction between the first conductor member and the second conductor member.

Abstract: A solenoid driving apparatus for actuating keys of a player piano is provided in which respective key striking strength data can be applied to respective solenoids of keys, so that musical tones can be reproduced correctly and in which the key striking strength data at the time of musical performance can be compensated for high fidelity reproduction. The solenoid driving apparatus includes a plurality of keys and solenoids provided on each key. When a key is depressed, a first key striking strength data corresponding to key striking strength and a data designating the depressed key are generated. The first key striking strength data is then converted into a second key striking strength data so as to make the latter data in linear proportion to an operating or response speed of the solenoid. In accordance with the second key striking strength data, a solenoid driving data is generated, and is applied to the solenoid corresponding to the key designated by the designating data.