Abstract: Apparatus for detecting note selection on a guitar fretboard including a differential amplifier for detecting voltage drops across successive fret pairs, a multiplexer for connecting successive fret pairs to the differential amplifier, counters for maintaining an indication of the string and fret position under examination, and a shorting string placed across the frets for insuring reliable circuit operation.

Abstract: A keyboard operated electronic musical instrument is disclosed which has a number of tone generators that are assigned to actuated keyswitches. Logic is provided for generating a note range signal for each preselected group of contiguous keyswitches in which the note range signal is selected for an actuated keyswitch. Musical effects such as vibrato and tone changes are selectively actuated in response to the note range signal. A mixture tone generator is described which uses a single set of harmonic coefficients which are translated and shifted in response to the note range signal.

Abstract: A keyboard operated electronic musical instrument is disclosed which has a number of tone generators that are assigned to actuated keyswitches. The tone generation is produced by sequentially and repetitively accessing a memory containing a set of data points which define a period of a preselected musical waveshape. Apparatus is described whereby a plurality of tone generators are implemented by each one selecting data points read out of the memory in response to a comparison logic.

Abstract: A method and apparatus for inhibiting the spurious recognition of new chords in an automatic chord recognition system by permitting a new chord group or chord type to be recognized only if the performer has operated the same or a greater number of keys since the last time an attempt was made to recognize a chord or the last time a valid chord was recognized.

Abstract: A keyboard operated electronic musical instrument having a number of tone generators which are assigned to actuated keyswitches. A tone selection means is implemented comprising an autocorrelation function generator. A set of harmonic coefficients is created by means of a discrete Fourier-cosine transformation of the autocorrelation function. A computing means transforms the harmonic coefficients to musical tones. The generated musical tones are varied in tone color by selecting the shape of the autocorrelation function. A means is provided to vary the autocorrelation function in a time variant manner in response to a control signal.

Abstract: Clavier multiplexing is used in the present keyboard musical instrument to reduce the number of sound generators needed by connecting them only to those notes that are depressed. The association of a tone generator with a control unit, which provides the tone generator with frequency, force, and speed information, continues as long as possible, and even after the associated note is released and until the control unit is needed to attend another note by use of independent address and idle-busy storage registers. The note address is digitally designated and remembered, sequential start up logic is used for a control unit. In the glissando mode, the address of the note of the pair involved in the glissando that was released last must be remembered, and the voltage-controlled oscillator involved must have continuing access to this address.

Abstract: A system is provided in which oral sounds are converted to instrumental musical notes. The system includes a digital memory adapted to store notes of different instruments and of different timbre. A variable address generator connected to the memory is adapted to retrieve the notes at various addressing rates in order to change the pitch thereof. The system is adapted to generate musical instrument output sounds in response to an oral input over a whole range of notes including pitches between whole and half tone increments in an unbroken frequency spectrum of pitch.

Abstract: A CPU provides control instructions according to key switch information supplied from a keyboard. An LSI receives the control instructions and generates a corresponding digital tone signal, which is converted in an acoustic system into an analog tone signal which is in turn supplied to a loudspeaker for producing sound. A power supply unit can be connected to the LSI and acoustic system through a transistor. The transistor is on-off controlled according to a power-off signal which is provided from the CPU according to a silent state signal generated from a power saving circuit in the LSI.

Abstract: Manually operable control apparatus for an electrical musical instrument such as an electronic organ having automatic chord circuitry which includes a plurality of spaced apart individually operable chord switches less in number than the number of chords available on the organ and connected to the chord circuitry of the organ through a multi-position gang selector switch arranged for a preselected different combination of chords at each of the different positions thereof. The chord switches permit individually activating any one of the individual chords in each of the preselected combination for each of the different positions of the gang selector switch.

Abstract: In a keyboard musical instrument employing waveform memory, a user may program the number and order of waveforms to be sequentially read out from a waveform memory containing a plurality of different waveforms.

Abstract: An electronic musical instrument having two keyboards is disclosed in which chords detected on the accompaniment keyboard are used to vary the selected tone color of the tones played on the solo keyboard. The solo tones are synthesized by means of a Fourier transform using a set of harmonic coefficients. Selected harmonic coefficients are scaled in magnitude in response to the chord type detected from the notes played on the accompaniment keyboard.

Abstract: A keyboard operated electronic musical instrument is disclosed which has a number of tone generators that are assigned to actuated keyswitches. A tone generation computation means is implemented using a combination of an even symmetric function and an odd symmetric function. One of these functions is scaled in magnitude in response to a modulation control signal. The scaled and unscaled functions are combined to produce a musical waveshape which is frequency modulated by changes in the level of the modulation control signal.

Abstract: An electronic musical instrument with a game function is capable of being used either to play music or to play a ball-hitting game. The electronic musical instrument comprises a keyboard having a plurality of keys for generating a first key data which is supplied to a musical tone generating circuit for producing a musical tone corresponding to the first key data, thus enabling to play music in a conventional manner. In addition, the electronic musical instrument comprises for use in a game mode a data generating circuit for generating a second key data representing a pitch of a key and varying its pitch in either one of directions to sequentially take a higher and a lower pitch respectively. The second key data is supplied to the musical tone generating circuit for producing a musical tone, thus simulating the movement of a ball. The second key data is compared with the first key data to generate a coincidence signal when both key data substantially coincide with each other.

Abstract: Disclosed is an electronic musical instrument with musical information input keys for producing musical information. A plurality of keys are provided for generating musical information of musical notes to introduce musical tones and pitches of the musical notes into the electronic musical instrument. A memory is included within the electronic musical instrument for sequentially memorizing the musical information. A musical generator is provided for sequentially reading out the stored musical information and providing an audio music in response to the stored musical information. The electronic musical instrument may function as an attendant feature of a conventional electronic calculator and/or an electronic timepiece. In a combined electronic musical instrument and calculator, the audio music can be utilized for announcing alarm conditions such as error, premature actuations of keys, overflow, voltage drop in power supply, etc.

Abstract: The present invention is an electronic piano that includes various "easy play" features that enable a person with little musical training to play the piano producing music similar to that of a skilled musician. The "easy play" feature automatically creates musical and rhythmic piano accompaniment patterns in response to playing either one key (One Finger Chord mode) or a chord (Funchords mode) with the left hand. The player plays the melody of the desired tune with the right hand. Instead of having to move the fingers of the left hand to play complex piano accompaniment patterns, as with a conventional piano, the player only needs to play a note or chord, and move the finger or fingers of the left hand to a different playing key or keys to change chords and patterns. In the standard piano mode, this instrument resembles an acoustic piano in function. The invention also includes a set of pushbutton switches which control the "easy play" features of the instrument.

Abstract: The present invention is directed to a bass-tone device for use with a piano. The device comprises a housing which can be mounted on a piano above the keyboard of the piano. A plurality of switches are mounted in the housing, and each of the switches has an engaging portion which extends from the housing and contacts a key of the piano when the key is in its normal undepressed state. The engaging portion of each of these switches moves to change the state of the switch in response to the depressing of the corresponding piano key. A bass-tone generator is mounted in the housing and the switches are connected to the generator. The bass-tone generator generates bass-tone signals in response to the change of state of the switches, which change states in accordance with the depression or raising of the piano keys.

Abstract: When a key among ten keys or function keys in a keyboard section is operated with a mode selection switch in a key input section set in a recording position, the note data corresponding to the operated key, flag data and tone duration data corresponding to that note data are stored as one-key play note data in a note memory. When a one-key play key is operated in a timed relation to a given rhythm after clearing an address counter in the aforementioned state, musical sound is generated according to the note data stored in the note memory, and at the same time note data is stored again together with flag data for auto play and tone duration data in the note memory.

Abstract: A tone generation system intended primarily for use in electronic musical instruments wherein a digital representation of a harmonically rich waveform is sampled, and a musical tone is produced therefrom. The stored waveform could be the four term Blackman-Harris window function, which has negligible side lobes and thus greatly attenuated higher harmonics. The stored function is read out at a fixed rate, but the time periods between successive readings of the waveform are varied to thereby vary the frequency of the output signal.

Abstract: A keyboard operated electronic musical instrument in which a number of tone generators are assigned to actuated keyswitches in which provisios are incorporated for simultaneously generating a combination of tones. Tones in the first family are generated with a maximum of Q harmonics by implementing a discrete Fourier transform employing stored sets of harmonic coefficients. Tones in the second family are obtained by operations on a frequency number and have a maximum of 2 Q harmonics. The second family of tones are generated in a manner that inherently provides ample noise reduction.

Abstract: A waveform of arbitrary complexity may be generated using a minimal number of circuit elements and minimal complexity by generating a frequency domain from a minimum set of base frequencies by storing lower octave frequencies of the minimal base set within a note memory. Selected octave and pitch, or note may be read from the note memory according to a list of notes to be thusly read as stored within a note list memory. Each of the instantaneous values of the base frequencies read from the note memory is then added in an accumulator to represent the instantaneous value of the sum of notes or tones comprising the complex frequency at that time. The application of process time periods will replicate an arbitrary complex waveform. Such a frequency generator can find wide application within electronic musical devices, tests and analysis instrumentation, communications and many other fields.

Abstract: A tone generator system for an electronic organ, which incorporates N programmable generators (where N is less than 12, and typically 7) which forms a system having the ability to sound notes of N different nomenclature tones at one time. A microprocessor controls the assignment of particular notes to each of the programmable generators, in accordance with the played keys of the keyboard(s) (and the tab switches, in the event that a partial footage is selected). Each of the programmable generators is connected to a chain of dividers and gates which are also under the control of the microprocessor. The information ascertained by the microprocessor from the keyboard(s) (and the tab switches) is used to control the selection of gates which control the passage of tone signals from appropriate dividers in the chains of dividers to an audio output system. More than one note of a particular nomenclature can be simultaneouly gated from the divider chain of a particular programmable generator.

Abstract: This is an electronic organ which economically simulates long duration aperiodic musical waveforms, such as the clash of cymbals. It employs the digital waveform generation technique, in which successive instructions are read out of a memory to determine the amplitude of the waveform at successive sample points. To save memory capacity, the memory addresses are rescanned; and to avoid audible discontinuities the scan direction recirculates numerically back and forth across the address field. Despite the bidirectionality of the scan, monotonic decreases in amplitude and in higher harmonic content are achieved. The monotonic decrease in amplitude is accomplished by impressing an exponentially declining envelope upon the digitally generated amplitudes. The monotonic decrease in higher harmonic content is accomplished by preventing the rescan from returning to a memory region of greater harmonic content after it has once entered a region of lesser harmonic content.

Abstract: A frequency divider which divides clock pulses to obtain the clock frequency of a desired dividing ratio comprises a binary counter, cycle data forming circuit and inhibit circuit to which the dividing ratio is fed in the form of the dividing ratio data.The counter counts the clock pulses, and the cycle data forming circuit converts the count value of the binary counter to a cycle data in which a certain single bit only becomes a logical state "1" and the rest of the bits are a state "0". The bit which becomes "1" in the cycle data is uniquely determined by the count value. Further, each bit of the cycle data becomes "1" in proportion to the weight of the each bit. With the cycle data being thus formed, the dividing ratio data is simplified.The inhibit circuit receives the cycle data and the dividing ratio data to suspend the counting operation of the binary count if the bit of the dividing ratio data corresponding to the bit of the cycle data whose state is "1" is also "1".

Abstract: A fiber optic musical instrument provides a design in which the musical notes and characteristic instrument sounds normally sensed by electro-mechanical devices such as magnetic pickups and acoustic transducers are generated by the modulation of light within optical fibers and are optically transmitted to amplifying devices without the need for externally mounted sensing devices.

Abstract: Apparatus is described to control the starting phase of a new tone for a keyboard operated electronic musical instrument having a number of tone generators. An interval detection subsystem is used to determine if a new note is separated by a given musical interval, such as an octave, from a currently generated musical tone. If the prespecified separation is detected the new tone generator is initialized so that its starting waveshape phase is equal to that of its related interval neighbor. Provision is incorporated to shift the new tone generator by a random frequency offset to phase unlock the octave intervals.

Abstract: A transparent operation plate is disposed on the operation panel of an input device in correspondence with tone information to be input. A pair of touch contacts are formed exposed on the surface of each transparent operation plate. A liquid crystal display element is disposed immediately below the transparent operation plate. The liquid crystal element displays characters representing the tone information, as well as the information input operation condition. This display can be visually confirmed through the transparent operation plate.

Abstract: An electronic musical instrument wherein purely digital techniques are utilized for generating the basic waveform train and also keying the waveform train so as to have the customary keying envelope with attack, sustain and decay portions. The wavetrain is a cyclically repeated series of four-term Blackman-Harris window functions, wherein there are preferably eight such functions in each series. A plurality of individual keying envelopes are generated by a piecewise linear technique, and these envelopes are assigned respectively to the waveforms in the series so that the relative amplitudes of the waveforms can change with time over the life of the tone. This results in modulating with time the harmonic content of the tone.

Abstract: An output processor for an electronic musical instrument, is characterized by a data distribution network interconnecting data processing means and data storage means, wherein at least one such data storage means stores data from which a waveform of the desired sound may be derived; means for producing a plurality of microinstructions from which sets of data flow control signals may be derived, said data flow control signals determining the source and destination of data being handled by said distribution network; and means for storage and retrieval of a program of said microinstructions, said program effecting control of data flow in a manner such as to allow the generation of the desired sound. Preferably said program effects control of data flow in a manner which allows the substantially simultaneous generation of a plurality of waveforms.

Abstract: A digital musical tone signal is generated in a first LSI selected by a chip select signal transferred from a CPU in accordance with a control signal transferred through a control bus from the CPU. Amplitude data and envelope data are transferred from a second LSI to the first LSI through data lines. In the first LSI, the digital musical tone signal amplitude- and envelope-controlled is transferred to an A/D converter where it is converted into an analog musical tone signal.

Abstract: Keys of a keyboard are divided into a plurality of tone ranges and a plurality of musical tone waveforms regarding specific ones of the divided tone ranges are stored in a waveform memory device. A number of the plurality of musical tone waveforms is smaller than the number of the divided tone ranges. An address signal generator is provided which generates an address signal having a repetition period corresponding to a tone pitch of a depressed key and supplies the address signal to the waveform memory device, and an arithmetic operating circuit is provided which selects ones from among the plurality of musical tone waveforms and mixes the selected ones of a mixing ratio, thereby forming a new musical tone waveform. The selected ones and the mixing ratio are predetermined corresponding to each of the tone ranges. Different tone colors of a number which is more than the number of the waveforms are realized for the respective tone ranges just like in a natural musical instrument.

Abstract: Compression and synthesis techniques and related apparatus for time domain signals, particularly signals whose information content resides in the power spectrum such as speech and more particularly signals whose amplitude is aperiodic, such as unvoiced speech sounds. Compression techniques include eliminating serially redundant segments of information. Synthesis, particularly of unvoiced sounds which are sensitive to injected artificial periodicity, involves repeating sequentially portions of the same segmentrepresentative of the source signal, including commencing and terminating at different points each repetition, varying the length of the portion and reproducing the portion forwards and backwards in time. The invention finds application in speech compression and compact speech synthesis devices.

Abstract: Equal-ratio scales offer a choice of semitone accuracies ranging from a thousandth cent to a millionth of a cent, any note of which may be selected as a reference for a fully chromatic just-intonation scale whose ratios are absolute and may be modulated in all 15 tonalities, i.e., to signature keys in seven sharps and seven flats.

Abstract: An electronic musical instrument by which a performer can provide a musical accompaniment in different musical styles. The performer selects a desired musical style and plays on a standard keyboard in order to express a desired harmony. The instrument translates the keyboard playing into a chord type and root that defines the harmony expressed by the performer. A processor generates parameter signals defining a segment of music including a plurality of accompaniment notes arranged in the selected musical style and related harmonically to the selected chord type and root. Output circuitry converts the parameter signals to sound so that a performer of limited skill or musical knowledge can play an appropriately-styled accompaniment to a melody written in any one of a variety of musical keys.

Abstract: Compression and synthesis techniques and related apparatus for time domain signals, particularly signals whose information content resides in the power spectrum such as speech. Compression techniques include adjusting the phase of harmonic components of a signal unit to obtain an equivalent power spectrum signal of a minimum number of discrete levels. The invention finds application in speech compression and compact speech synthesis devices.

Abstract: An electronic musical instrument comprises a tone generator which generates tone signals having tone pitches as designated by playing keys and tone properties as determined by control data signals applied thereto. A set of control data signals are provided in a digital format and delivered timewisely in serial form to manual setting units. The serial signals are converted into parallel signals and applied to the respective setting units for desired adjustment. The adjusted or non-adjusted parallel signals are converted back into serial signals and applied to the tone generator. Interpolator circuits are provided between the setting units and the tone generator to apply the latter control data signals whose values vary gradually even when the values of the signals from the setting units exhibit abrupt large changes from certain values to another.

Abstract: A hand-held electronic musical instrument and system has a plurality of resistance elements that have adjacent thereto indentations or notches, or other tactile structures for locating discrete notes. Each resistance element is connected to a circuit for translating the position of the musician's finger on the element into an electrical signal, the frequency of the signal corresponding to the position touched. Transducers convert the electrical signals into sounds, which are modified by an acoustic cavity within the instrument. At least one control panel is provided on a side of the instrument engaged by the thumb or thumbs of the musician, each control panel also being a one-dimensional touch panel with the control axis perpendicular to the long axis of the panel so that the musician's thumb can slide along the panel parallel to the long axis without changing its position in the control axis. The musician controls the volume of the sound by adjusting the position of the thumb transverse to the instrument.

Abstract: The present invention is a chord teaching system and method which assists the organist in learning musical chords. The system functions in several different modes and the various modes are selected by the learning organist. The chord teaching system enables the learning organist to select a chord without demonstrating any knowledge of the correct finger position on the keyboard of the organ necessary to play the chord. The system, depending upon the mode of operation, plays the chord selected and indicates to the learning organist the key corresponding to the root note of the selected chord or indicates to the organist the keys corresponding to the notes of the selected chord or enables the organist to depress the keys that the organist believes form the selected chord and indicates a correct response if the organist depresses the proper key and indicates the correct keys that form the notes of the chord if the response is incorrect.

Abstract: A digital semiconductor circuit for an electronic organ has a plurality of control inputs addressed via a keyboard and corresponding in number to the number of keys of the organ keyboard, and a plurality of audiofrequency signal inputs addressed with periodic electrical oscillations by an oscillator system. Each control input is associated with a respective key of the keyboard and each audiofrequency signal input is permanently assigned with a respective tone frequency of the highest octave of the organ. The control signals serve to address the control inputs by the keys of the keyboard corresponding to logical levels "1" and "0." The circuit further includes a number t of divider stages in a frequency divider at least equal to a number q of the octaves in the organ keyboard. A number u of a plurality of AND gates in a given group of AND gates is greater than the number q of the octaves in the organ keyboard.

Abstract: An electronic musical instrument in which harmonic coefficients stored corresponding to tablet signals are read out and synthesized by using a discrete Fourier transfer to form a desired musical sound. The format of cut back by a combination of a tone to be cut back, a key number and harmonic coefficient is predetermined, and based on the predetermined tone and key number respectively detected by tone detecting means and key number detecting means, the harmonic coefficient of the predetermined combination is read out, thereby to effect cutting back of the predetermined tone.

Abstract: An electronic musical instrument which can be manufactured at low cost using a system of generating frequency information corresponding to the note of each key as a frequency number on a non-real time basis. The electronic musical instrument is provided with a frequency number memory for storing the frequency number corresponding to the note of each key and delivering the frequency number corresponding to key information from a key assignor, means for executing an operation in units of the delivered frequency number a plurality of times and transferring the operation result to a buffer memory upon each execution of the operation, and a memory for storing the results of the operation executed the plurality of times.

Abstract: A percussion generator for an electronic musical instrument, such as an electronic organ, wherein the percussion generator is responsive to a time division multiplexed serial data stream produced by scanning the keys of the keyboard. A control pulse is produced each time that a new key on the keyboard is depressed, and this pulse, which has a duration equal to or greater than a plurality of scans of the keyboard, is employed to produce a burst of keydown pulses in the data stream. The percussion generator is responsive to the serial data stream and each of the aforementioned control pulses to produce keydown pulses in the appropriate time slots of the data stream in a plurality of successive sequences thereof and then terminate the keydown pulses even though the associated keys remain depressed.

Abstract: The present invention relates to economically fabricated means for the generation and processing, member selection, and acoustic radiation of pluralities of individual tone currents originating from at least one high frequency source and formed by note-information temporarily transferred through key depression, from permanent electronic memories to temporary memories in small numbers of standard tone units, in precise duplication of properties of pipe organ sound.There is described an electronic transfer organ for duplicating twenty-six known properties of pipe organ sound. The illustrative, inventive instrument employs completely standardized circuitry except for automatically programmable memories for each organ voice, which contain all the information required to form, switch and variously decouple all the notes in that voice.

Abstract: Tonality designation of an electronic keyboard instrument is realized by utilizing keys instead of conventional tonality designation switches provided on the panel of its.The tonality designation system comprises a tonality data forming circuit and a memory. The tonality data forming circuit generates tonality data consisting of keynote data and scale data representative of key note and type of scale respectively based on key depression and transfers it to the memory in advance before performance. The memory stores the tonality designation data during performance. A musical tone to be produced is formed or controlled based on the stored tonality data and a depressed key.

Abstract: A power saving device for an electronic musical instrument in which when the electronic musical instrument is idle, or no key operation by an operator takes place for a given period of time, a power source is automatically turned off to thereby prevent wasteful power consumption.

Abstract: A predetermined frequency signal is amplitude modulated with a time window signal having a predetermined time width to simultaneously calculate a plurality of frequency components distributed over a predetermined frequency bandwidth and having the frequency component as a center component, and the plurality of frequency components thus calculated are used as partial tone components to form a musical tone signal. The frequency signal and the time window signal are formed by using a common function signal generator, on a time division basis, which produces the frequency signal and the time window signal. This construction makes it possible to form a musical tone having a great number of harmonic components at high speeds with a simple circuit construction.

Abstract: The disclosed organ employs keyboard-activated transfer of individualized tone and envelope-generating information from large memories for each distinctive set of a note's harmonics, to small memories in small circuits corresponding to each harmonic set. Selection of large memories programmed for different temperaments or voice types renders the organ playable as one or another type of organ (e.g., gothic, classical, romantic, theater) in a variety of temperaments (e.g., just-temperament, mean-tone, equal-temperament). Information transferred from any selected large memory causes a circuit common to one or more sets of a note's harmonics to sweep the harmonic data transferred to the small memories for all the note's harmonic sets, to generate respective currents representing attack and decay envelopes for all the note's harmonic sets.

Abstract: An electronic musical instrument comprising a tone generator, an accumulator and a digital filter. The tone generator generates musical tone signals each represented by sampled values, corresponding to depressed keys. The accumulator accumulates the sampled values of the musical tone signals at predetermined timings. The digital filter modifies an output of the accumulator in accordance with the amplitude-frequency characteristic of a predetermined formant characteristic. A musical tone is produced based on an output of the digital filter circuit, thereby the formant characteristic is imparted to the musical tone.This utilization of the digital filter for the musical instrument makes it possible to impart a formant characteristic to a musical tone without a complex circuit construction. Moreover the insertion of the accumulator following the tone generator makes it possible to use the digital filter of a low speed type.

Abstract: A waveform synthesizing apparatus is provided for producing a desired synthesized waveform by adding partial waveforms together. In this apparatus, the times within a cycle wherein a fundamental and harmonics of a desired wave to be output are stored in the circuitry. Peak values of each partial waveform are formed at the prestored times and output at frequencies, which correspond to or exceed sampling frequencies required by each partial waveform. These partial outputs are fed to low pass filters. Each filter has a cut-off frequency component corresponding to each of the output frequencies to remove therefrom clock components. Outputs of the low-pass filters are added together to obtain a synthesized waveform.

Abstract: The present invention provides a system for communicating data among microprocessors which are utilized to control an electronic musical instrument. A master microprocessor transmits a synchronizing signal comprising two, spaced pulses to the other microprocessors causing the other microprocessors to interrupt their operations and become synchronized with the synchronizing signal. Thereafter, according to a prearranged sequence, one microprocessor commences transmitting data while simultaneously the other microprocessors commence inputting data.

Abstract: The system comprises a frequency number memory device for storing information regarding the frequencies of respective tones, a keyboard switch for reading out frequency number information corresponding thereto from the memory device, an address generator including an adder for adding a predetermined number of the frequency number information thereby producing an address signal consisting of plural bits, address composers for processing the bits of the address signal and thereby composing digital tone signals constituting a saw-tooth, square and triangular waveshape, and digital-analog converters for converting the digital tone signals into analog tone signals, which are thereafter used to synthesize waveshapes of any tone.