Abstract: An electronic percussion instrument may include a percussion member that generates vibrations when percussed, a vibration resonance member, a vibration damping member, and an electronic sound generation unit. The vibration resonance member may include a hub portion, a plurality of radial portions extending radially from the hub portion, and a plurality of spiral portions. Each of the spiral portions may be disposed between and connects respective two of the radial portions. Each of the radial portions may be connected to a respective adjacent one of the radial portions by one or more of the spiral portions. The vibration damping member, disposed between the percussion member and the vibration resonance member, may propagate the vibrations generated by the percussion member to the vibration resonance member. The electronic sound generation unit, connected to the vibration resonance member, may sense the vibrations through the vibration resonance member and generate an electronic percussion sound.

Abstract: A portable musical instrument capable of triggering a percussion synthesizer by striking of fingers on a plurality of transducers. The ergonomic shape of the instrument is similar to a guitar, with a set of transducers on the body for one hand and another set of transducers on a rotated head for the other hand. The arrangement of transducers is placed so that minimal finger travel is necessary to play a variety of sounds rapidly and comfortably. Transducers are plugged into to a configurable central circuit board assembly in the body, which are in turn is connected by cable to a percussion synthesizer interface box. The interface box is connected to a percussion synthesizer by standard 1/4" phone plug cables. Certain transducers and switches control additional parameters of a percussion synthesizer including hi-hat position and patch selection.

Abstract: For imparting a sostenuto effect to a series of sounds produced by key depressions successively repeated in an electronic musical instrument, a searching device searches a first memory device for a first memory channel which has already stored a note information identical with the note information produced on the basis of the repeated key depression, and, then a setting device is actuated in the presence of aforementioned first channel and operative to copy the sostenuto information indicative of the instruction of imparting the sostenuto effect from a second channel paired with aforementioned first channel having already stored the identical note information to the second channel paired with another first channel where the note information produced by the repeated key depression is newly stored, thereby imparting the sostenuto effect between tones produced by repeated key depressions.

Abstract: Calculations by an envelope circuit and a waveform calculation circuit, which are principal functions of an electronic musical instrument, can be performed by the same calculation routine through use of the same general formula A=B.+-.C.times.D. Accordingly, their circuit structures are substantially simplified and the circuits can be fabricated as a one-chip large scale integrated circuit.

Abstract: An electronic bell-tone generating system selectively provides a plurality of bell tones having improved tonal quality includes a plurality of tone generators operated in preselected combinations by a microprocessor in response to inputs from a keyboard. Data representing characteristic bells, including a fundamental tone and associated partial tones, their initial amplitude, and decay rate, is stored within a random access memory, input periodically to the respective tone generators comprising double-buffered, digital-to-analog converters, and output simultaneously to produce the "strike" of a bell.

Abstract: A shaped waveform tone generator circuit is contained entirely in an integrated circuit and has a pair of push-pull amplifiers for driving a piezo-buzzer. The output from an RC network controls current flow in a first follower transistor connected to one voltage source and in a second follower transistor connected to a second voltage source. A pair of CMOS switches alternately connect the inputs of the amplifiers to the first and second transistors. A tone signal controls operation of the two CMOS switches.

Abstract: A plurality of drum pads are each provided with a respective piezoelectric pick-up. The output of each piezoelectric pick-up is fed to a corresponding envelope-extracting circuit. The envelope signal extracted by the envelope-extracting circuit is converted by an A/D converter into a digital signal which is fed to a CPU. The CPU feeds a tone designation signal to a tone generator unit according to parameter data from a parameter data setter and the digital signals noted above, thereby causing generation of a corresponding drum sound.

Abstract: A whistle synthesizer comprises a microphone, a housing, system electronics within the housing, and controls outside the housing. The player whistles into the microphone, the signals from which are processed to provide an instrument output signal suitable for communication to an external amplifier. The controls are located within easy reach of the player so that they may be manipulated all the while the player is whistling.

Abstract: An electronic musical instrument includes a first waveform memory for storing a waveform corresponding to an attack portion of a musical tone and one period of a steady waveform produced after the attack, a second waveform memory for storing one period of a waveform different from the contents of the first waveform memory, a waveform reader which reads out the first and second waveform from the first and second waveform memory, respectively, and an envelope generator which generates two separate envelope signals. The first waveform including the attack portion of the musical tone and the periodic second waveform are multiplied by the separate envelope signals, respectively, and then the products of the multiplication are added together. The sum of the products is provided as an output.

Abstract: An acoustic output device for a personal computer includes an envelope setting circuit for setting elements of a tone including an envelope pattern, a first storage circuit for storing the element data of the tone, a music note setting circuit for setting note information of a music, a second storage circuit for storing the note information, and an acoustic output circuit for reading-out the note information and providing a tone with the element data.

Abstract: A CPU reads out sampled waveform data stored in a waveform memory and detects a peak value of the read-out data for each predetermined block using working registers, thereby obtaining an interpolated envelope curve. The CPU then divides the sampled waveform data by the interpolated envelope curve to obtain a normalized sound waveform without any envelope in an original sound signal.

Abstract: An electronic musical instrument includes a memory in which digital samples of an aperiodic waveform are stored. Digital samples stored in a first portion of the memory represent a rapidly rising portion of the waveform and those stored in a second portion of the memory represent a rapidly declining portion of the waveform whose amplitude and spectral energy distributions are equalized. The first memory portion is addressed in forward scan and subsequently the second memory portion is addressed recyclically in forward and rearward scans to generate an output waveform having a first part corresponding to the rising waveform section and a second part corresponding to a series of the recyclically addressed versions of the equalized waveform section. After delivery of the first part of the output waveform, a monotonically declining envelope is impressed upon the amplitudes and the spectral energy distributions of the second part.

Abstract: A switched capacitor filter system is provided which is programmed to filter a predetermined sequence of tone signals. The filter system is de-rung after each selected tone signal is detected by increasing the clock frequency of the switched capacitor from the programmed value corresponding to a tone signal up to a center frequency substantially greater than that of the tone signals. Energy stored in the filter system is thus quickly dissipated. Rapid sequences of sequential tone signals are thus filtered without the problems associated with ringing of the filter.

Abstract: A step signal of which the period varies according to random data is derived from a step pulse generator, and is supplied to an address counter. By the output data from the address counter, an address of a waveform ROM is specified. From a waveform ROM, the waveform based on the random data is output in the form of a distorted waveform signal. Using this output signal of the distorted waveform, a cymbal sound, for example, is generated in a musical tone generator.

Abstract: An electronic musical instrument includes a first memory in which audio samples of lower frequency components of an aperiodic waveform are stored and a second memory in which audio samples of a higher frequency components of the waveform are stored. Digital samples stored in a first portion of the second memory represent a rapidly rising portion of the higher frequency waveform and those stored in a second portion of the memory represent a rapidly declining portion of the higher frequency waveform whose amplitude and spectral energy distribution profiles are preferably equalized. The first memory is addressed throughout in forward scan to generate a first output waveform. The second memory is addressed in an initial forward scan throughout its first and second portions and the direction of scan is reversed at the end of the second portion to recyclically address it in rearward and forward directions to generate a second output waveform, which is combined with the first output waveform.

Abstract: The realism by which the sound produced by various musical instruments may be electronically simulated is enhanced by the storage of digital data commensurate with scanning values of several periods of a note including the release portion thereof. Command words are also memorized and, in response to the reading of a command word and the state of the input command to the instrument by the player, indicative of whether the note is to be sustained or terminated, the reading of a command word may cause the addressing of the waveform memory to be jumped to the release portion where the read-out will be continued from a scanning value approximately equal to the value read immediately prior to the reading of the command word. The waveform memory may contain a segment of the sustain portion of the note which will be repetitively read so long as the player's input command indicates that the note is to be sustained, the repetition also being in response to memorized command words.

Abstract: A touch response apparatus for an electronic musical instrument wherein a nonlinear analog-to-digital conversion is effected using a single A/D converter in correspondence with a plurality of keys, and wherein touch data are proportional to the period of time and amplitude value of an envelope waveform.

Abstract: A musical tone generation device of waveshape memory type stores, in its memory, waveshape data of an entire part of a rising portion of a musical tone waveshape and waveshape data of only a part of a remainder portion succeeding to the rising portion. The rising portion data is read out once while the remainder portion data is repetitively read out from the memory thereby to reproduce the entire musical tone waveshape. By changing a rate for the repetitive readout operation, a pitch of the musical tone waveshape at the portion succeeding to the rising portion can be changed with passage of time.

Abstract: The sound generator applies an envelope to the note signal. Current to the sound producing element is controlled by a series transistor whose base is driven with a signal having a frequency corresponding to the musical note. The driving voltage applied to the base has a voltage amplitude corresponding to the voltage stored in a capacitor connected through a resistor and discharging through said resistor and the base of the transistor controlling the current to the sound producer.

Abstract: Analog output signals of a key touch sensor and tonal effect setting manual operators are respectively time division multiplexed and thereafter are converted to digital signals by using an analog to digital converter on a time shared basis. The key touch sensor capable of detecting a key touch of a depressed key can also be used for obtaining an initial touch detection signal by additionally providing a device for holding a peak value of an output signal of the sensor at the beginning of depression of the key. Control factors of various tonal effects are controlled in response to these converted digital signals. Control factors of an attack pitch control effect are controlled in response to the key touch. In imparting a delay vibrato effect, the attack pitch control is automatically applied before the delay vibrato is initiated. In imparting a vibrato effect, the attack pitch control is automatically applied and the vibrato is applied thereafter if a key has been depressed in a staccato form.

Abstract: An electronic music note generator having a volume control circuit using an RC network to control sound amplitude. Signals are formed by the discharge characteristics of an RC network and the voltage level at charging determines the volume of the sound produced. Reverberation characteristics are provided by a persistence in the signal between notes as a result of the RC discharge characteristic.

Abstract: The differentiation data of a basic waveform is read out from a differentiated value waveform memory at a clock timing corresponding to a musical scale of an operated play key, and it is multiplied by an envelope value of a musical sound waveform to form a musical sound waveform differentiation value. In parallel therewith, the differentiation data is accumulated at the clock timing to form a compensative value. The compensative value is added with the musical sound waveform differentiation value at the point of time at which the envelope value is changed to cancel a DC component which would otherwise develop in a produced musical sound waveform. The musical sound waveform differentiation values thus compensated are accumulated, and are subjected to digital-to-analog conversion, so that the musical sound waveform free from the DC component is produced.

Abstract: Under the presence of an internally generated mandolin clock (MDN) or an externally generated mandolin clock (MDN'), an envelope clock (ENV-CLK) obtained in accordance with a lower bit output having three-bit signals (including the LSB) is supplied through AND gates to an envelope counter. The counter is set in an up count state in response to an output from a flip-flop set in response to a key on pulse. When a carry signal is generated by the envelope counter, the counter is set in a down count state. In the latter case, the fourth-bit signal from the LSB of the output from the binary counter is gated through the AND gate. The envelope counter counts down the envelope clock (ENV-CLK) having a period twice that of the envelope clock (ENV-CLK) in the up count state.

Abstract: A touch response apparatus for an electronic musical instrument wherein a nonlinear analog-to-digital conversion is effected using a single A/D converter in correspondence with a plurality of keys, and wherein touch data are proportional to the period of time and amplitude value of an envelope waveform.

Abstract: In a waveshape memory, a first waveshape of plural periods including an attack portion and a second waveshape of plural periods are stored. A tone waveshape signal is produced by reading out the first waveshape once and thereafter reading out the second waveshape repeatedly. The first waveshape is a first section including an attack portion cut off from a desired original tone waveshape. The second waveshape is principally composed of a second specified section succeeding the first specified section cut off from the original tone waveshape. A terminal portion in the second specified section is weighted with decay characteristics and is added with a corresponding terminal portion of the first specified section which has been weighted with attack characteristics, thereby effecting smooth connection between the respective waveshapes.

Abstract: A touch sensitive system for an electronic musical instrument providing a multiple key switch contact system for effecting control over two or more tone generating systems. The first tone generating system operating rapidly in response to the actuation of the key switch to produce a desired voice. The second or subsequent tone generating systems operate sequentially in a delayed manner on the actuation of the key switch effecting a predetermined delay in the production of the desired voice. The audio output of each of the tone generating systems is summed forming a resultant waveform for audio amplification. The key switch actuation, depression and release, causes the tone generating systems to respond immediately to the depression or release of the key switch which effects a change in the envelope characteristics of the resultant waveform.

Abstract: A method and apparatus for reproducing the complete attack transient and steady state portions of a waveform is disclosed.

Abstract: A musical instrument with a plurality of vibratile tone generators, whose oscillations are converted into alternating currents by electroacoustic transducers, is provided with a control circuit feeding back a regenerative vibratory signal of progressively diminishing amplitude to maintain the oscillations of a previously activated tone generator for a selected fade-out period. The duration of the fade-out period can be controlled by the player, e.g. with the aid of a pedal, by varying the time constant of a peak-storage network connected to the feedback loop. The feedback signal may be transmitted to the respective tone generator by a mechanical vibrator attached to the instrument body or by sound waves emitted from a loudspeaker. The player may also switch from the output of the peak-storage network to a constant control signal for sustained reverberation.

Abstract: Disclosed is a musical envelope control device which is used in an electronic watch with a melody alarm function.

Abstract: A control signal-multiplexing circuit for producing various forms of multiplexed control signals from control signals of a plurality of channels. The circuit comprisesa multiplexer for selecting control signals of a plurality of channels by scanning and multiplexing the control signals by time division; anda control signal converting circuit which is supplied with output signals from the multiplexer, converts the signals of the respective channels included in the output signals into various forms of control signals, multiplexes the control signals, and sends forth the multiplexed control signals to the corresponding control lines.

Abstract: A method and apparatus for interpolating between the harmonic structures of a waveform stored in memory during portions or the entire transient periods of said waveform. In an electronic musical instrument having a greater number of selectively actuable switches than note generators to cause the production of sounds corresponding to the respective notes of a musical scale, the present invention interpolates between the harmonic structures of a waveform stored in memory during portions or the entire transient periods of said waveform. This is accomplished through the use of memory units having a number of locations or zones within each memory where the number of zones is equivalent to the number of discrete harmonic structures.

Abstract: An envelope wave shape for each musical tone wave shape is generated per each key operation. The rate of change of the envelope wave shape to be generated are switched at timings corresponding to key operation speed of an operated key, thereby enabling an electronic musical instrument to generate musical tones of different envelope patterns depending on key operation speed just like on a pipe organ.

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: 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: Waveform data for converting attack, decay and release status sections of a musical sound envelope into an exponential function waveform is obtained from an envelope generator wherein exponential function waveform data is read out from a ROM or obtained through calculation based upon an exponential function in a digital logic processing circuit, and it is used for the envelope control of a tone signal from a digital wave generator.

Abstract: A key-speed-responsive volume control apparatus for a keyboard-type electronic musical instrument includes a key switch associated with a key of the instrument, wherein a movable contact of the key switch moves out of engagement with a break contact and into engagement with a make contact upon depression of the key. A capacitor is charged following the movement of the movable contact out of engagement with the break contact and before engagement with the make contact. The capacitor is made to discharge at a first prescribed rate immediately after charging until the movable contact comes into engagement with the make contact, and then at a second prescribed rate until the movable contact disengages the make contact upon release of the key.

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: Envelope curves for a large number of individual sounds to be digitally synthesized are generated by storing sample envelope shapes. The duration of the stored curves is varied by exercising control over the sampling of the stored envelopes. The smooth transition from one envelope curve to another is accomplished by sampling the new curve at a fast rate until substantially matching values of the previous and new curve are found and then proceeding with the sampling of the new curve at the desired rate.

Abstract: In the generation of an envelope waveshape of a musical note to be produced in response to a key depression, speed parameters of the envelope which are determined corresponding to the speed of its attack, decay and release are produced digitally. The envelope waveshape is obtained by calculations based on the speed parameters. The formation of the envelope waveshape of the musical note, its volume level control and its tone control can be achieved with simple arrangements.

Abstract: An electrical sound output signal from an acoustical-electrical or piezo electric transducer instrument is made available at selectively switched high and low signal levels by level control apparatus utilizing bistable switching of first and second attenuated electrical sound output signals. A flip-flop circuit toggles between first and second states in response to an input signal pulse generated by actuation of a footswitch. Oppositely-phased output signals produced by the flip-flop are applied to first and second switching FETs controlled thereby so as to be alternately conducting. The FETs are connected between respective first and second attenuators providing high and low level-controlled sound output signals and common output terminals. Accordingly, upon selective actuation of the footswitch, either high or low level controlled sound output signals can be made available at the output terminals.

Abstract: The string snub effect functions so as to introduce a different set of parameters for the harmonic content, envelope amplitude, shape and rate of decay and pitch of the resulting sound upon key release when a percussive string-type voice is selected in an electronic musical instrument. The apparatus for causing a snubbing of the resulting tone comprises a means for selecting a percussive string-type waveform and for generating a signal indicative of such selection, a means for detecting the release of a depressed key and the presence of the signal indicative of the selection of a percussive string-type waveform and for generating a signal indicative of such detection, a means for halting further interpolation of the selected waveform and switching to a preselected harmonic structure of said selected waveform, means for shifting the pitch of the generated tone of said selected waveform, and means for variably controlling the envelope amplitude, shape and rate of decay of the selected waveform.

Abstract: A touch responsive envelope control system is provided for use in an electronic musical instrument having a multiplexed keyboard, a plurality of assignable tone generators, each being assignable to producing a single note of one or more notes corresponding to one or more actuated keys of the keyboard and a keyer associated with each tone generating means for keying the generated tone with controlled attack time and decay rate and a controllable peak amplitude. The touch responsive system comprises a peak amplitude control system responsive to the actuation of each key for keying the associated tone with a peak amplitude corresponding to the intensity of actuation thereof. The peak amplitude control system includes an encoding circuit responsive to the actuation of each actuated key for producing an encoded intensity signal corresponding to the intensity of actuation thereof and a decoding circuit responsive to each encoded intensity signal for producing a corresponding peak amplitude control signal.

Abstract: A musical door chime which includes a repertoire of musical tunes one of which is played when a door pushbutton, preferably the front door pushbutton, is actuated. The musical tune which is played may be selected by means of a keyboard connected to a microprocessor. Digitally encoded representations of the notes of each musical tune are stored in a memory. Each digitally encoded musical note is read from memory by the microprocessor and converted by the microprocessor into a squarewave having the frequency and the duration of the note. The microprocessor is connected to a note strike and decay circuit which is preferably connected in series with an active audio filter circuit for translating the squarewave into a sinusoidal output for energizing a loudspeaker so that relatively high quality audible tones are heard when the musical tune is played.

Abstract: A multiplexed electronic organ utilizing a plurality of integrated circuit chips, each chip time division multiplexing selected keying envelope time constant signals from a switched capacitor time constant generator for two alphabetic notes over the entire frequency range of a spinet or for one alphabetic note over the entire frequency range of the manuals and pedals of a console organ. The same integrated circuit chip is used for both spinet or console organs. Each chip contains a multiplexer circuit which isolates the multiplexed keying envelope output signals from the time constant generator and includes as a coupling means a plurality of switching element arranged into groups. Some of the groups are interconnected to provide the keying envelope time constant signal normally intended for one frequency range to the output associated with a different frequency range.

Abstract: Circuit means for synthesizing the sound of a mechanical bell by combining the three most significant frequencies of the bell to be synthesized and modulating these with a decaying exponential control signal which is derived from a clock signal having a pulse repetition rate equal to the stroke repetition rate of the bell being synthesized. The combined and modulated signal is amplified and coupled to suitable audio distribution means. Modulation of the exponential signal can provide a tremolo effect.

Abstract: A circuit for producing musical tones is disclosed which includes a keyboard for selecting the musical tones, and a tone generator responsive to the keyboard for generating a square wave signal having the frequency of the musical note to be generated. A charging circuit is provided for charging a capacitor to a predetermined level of voltage when the square wave signal is terminated, and for exponentially discharging the capacitor when the square wave signal is initiated. A modulation circuit amplitude modulates the square wave signal in proportion to the capacitor voltage to produce an exponentially decaying signal which simulates the waveform produced by a struck piano string. A speaker is also included to convert the exponentially decaying signal into audible musical tones having the sound of piano notes. The circuit of the invention requires only a small number of components, making it suitable for use in miniature musical toys.

Abstract: The invention relates to a circuit for synthesizing either simple or complex waveforms of the type used in electronic musical instruments, such as electronic organs. In the specific embodiment disclosed herein, the synthesizing circuit is utilized in a rhythm unit for producing a damped sine wave charateristic of certain drum sounds. Opposite polarity waveforms are simultaneously produced by a switched capacitor technique driven by an attack/decay clocking signal and under the control of a keying signal received from a suitable low frequency rhythm clock source. The positive and negative waveforms are alternately selected in order to produce bipolar pulses at the frequency of the desired tone, and these pulses are connected to the input of a switched capacitor filter that modifies the pulses to produce a sine wave signal having an amplitude following that of the desired damped envelope.

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.

Abstract: A fully digitalized function-of-time generator suitable for use as a tone envelope generator in a digital electronic musical instrument, comprising: a clock pulse generator for generating a clock pulse at a selectable rate; a gate enabled at each arrival of the clock pulse; a single-stage binary shift register for successively shifting out its contents as a digital word representing the instantaneous values of a desired function of time synchronously with the clock pulse; a digital subtractor; a digital multiplier; and a digital adder, all of these members being interconnected to each other to be operative so that the output of the register is subtracted from a first set value representing a digital word, the resulting difference being multiplied by a second set value representing a digital word, the resulting product being added to the output of the register via the gate, so that the resulting sum is loaded into the register.

Abstract: An envelope generator is provided with a count circuit the count value of which is varied through addition or subtraction or combination thereof, and a conversion circuit which operates to convert the count value into amplitude data, so as to generate an envelope having a shape corresponding to variations with time of the count value. According to one aspect of the invention, the count circuit is a circuit which carries out computation for exponentially varying the count value through polygonal line approximation, so as to form an envelope of exponential characteristic. According to another aspect of the invention, the conversion circuit is a memory which has stored amplitude data corresponding to count values in advance so as to convert count values in the last linear region of the envelope obtained by the polygonal line approximation into amplitude data in exponential relation and to convert count values contained in the remaining polygonal line regions into amplitude data in linear relation.