Abstract: Reading of a waveform memory is controlled and one of different processing is performed depending upon which of a first mode and a second mode has been designated. When the first mode has been designated, an interpolation operation is performed on the basis of plural sample value data read from the waveform memory by using a predetermined number of processing time slots and a resulting one waveform sample value data is produced. When the second mode, has been designated, a processing for producing one waveform sample value data is performed on the basis of one sample value data read from the waveform memory by using one processing time slot. By using a predetermined plural number of processing time slots, one waveform sample value data produced with a high accuracy in the first mode whereas plural waveform sample value data are produced in the second mode whereby generation of a waveform can be performed efficiently by properly utilizing the mode.

Abstract: A method for processing a digital signal produced by digitizing an analog signal such as a musical instrument sound signal, and an apparatus for producing sound source data. When the input signal contains a periodically repetitive waveform portion, the fundamental frequency and its high harmonic components of the input signal is extracted by a comb filter prior to signal processing which takes advantage of the periodicity of the input signal. The fundamental frequency or pitch is detected by performing Fourier transform to produce frequency components, phase matching these frequency components and performing inverse Fourier transform. When extracting a repetitive waveform portion or so-called looping domain, such looping domain having the highest similarity in waveform in the vicinity of both ends of the domain is selected.

Abstract: A musical tone control waveform signal generating apparatus is provided in order to generate a musical tone control waveform signal by which a musical tone generated from an electronic musical instrument is to be controlled. The musical tone control waveform signal is varied in its envelop level by each of time-division sections to be passed over a lapse of time. For instance, when a key-depression event is occurred, this musical tone control waveform signal of each time-division section is formed by carrying out a computation by use of parameters which are preset with respect to each section. Preferably, the parameters concern with the variation rate and target level of the musical tone control waveform signal to be formed by each section.

Abstract: An electronic musical instrument according to the present invention has oscillators for generating a tone waveform; a modulator for modulating a musical tone; a modulation controller for determining a degree of modulation to be performed by the modulator; and a central control unit for controlling the oscillators, the modulator and the modulation controller. A memory stores a current control value of the modulation controller, and an input/output device reads a control value stored in the memory, by the central controller, and/or writes a control value stored in the memory into the central controller to ensure the control of the degree of modulation and the alteration of frequency bands.

Abstract: An envelope generator for an electronic musical instrument, in which a current value of the envelope approaching asymptotically to a target level, using a subtracter means for subtracting from data representing the target level in a floating point representation, data representing the difference between the target level and the current value in a floating point representation with deeming these data as fixed point data each having a decimal point between an exponent part and a fractional part, and a comparator for comparing the output of the subtracter means with a predetermined constant, and for judging that an envelope phase transfer condition is met if the output of the subtracter is greater than the constant. The envelope generator can achieve a phase transfer control function substantially similar to prior art envelope generators by a small amount of hardware.

Abstract: Tone waveform data is divided into plural data segments, so that frequency and magnitude of respective spectra contained therein are analyzed for each of the data segments. Analyzation parameters indicative of the frequency and magnitude of the respective spectra for each said data segment which has been obtained through the analyzation is stored into a memory. The analyzation parameter for each data segment is sequentially read out from the memory, and the tone waveform data is reanalyzed on the basis of the read-out parameter. To control the frequency of a resulting tone, a data shift circuit may be provided which serves to shift the value of the frequency data contained in the analyzation parameters.

Abstract: An electronic sound generating apparatus which generates sound or recreates music performance according to the data included in a bar code. The apparatus includes a scanner to scan a bar code. Attributes of sound or music are assigned to parameters of control data for synthesizing sound or recreating music performance. Each of the parameters is given a specific value by the data included in a bar code scanned by the scanner. The resulted sound or music performance is provided with random, accidental, and unexpected characteristics, and an operator need not perform inputting operation to vary sound or music performance.

Abstract: Timbre control apparatus, for an electronic musical instrument that, in response to a tone-ON command, reads timbre data from storage memory where a plurality of timbre data to be employed have previously been stored, and produces musical tones in consonance with the timbre data. The timbre control apparatus has a first storage memory for storing first timbre data common to all tone ranges; a second storage memory for storing second timbre data inherent to specific tone ranges; a calculation circuit for, in response to a tone-ON command, performing a predetermined calculation employing the first timbre data read from the first storage memory and the second timbre data read from the second storage memory; and tone production circuit for producing a musical tone having a predetermined timbre in consonance with data calculated by the calculation circuit.

Abstract: A sound synthesis process. The invention relates to an additive sound synthesis process, as shown in FIGS. 1A and 1B, in which sample blocks (16) are determined by performing the inverse Fourier transform of successive frequency spectra. The time-superimposed sample blocks (16) are added in order to form a sequence of samples representing the reconstituted sound wave.

Abstract: An automatic performance apparatus stores performance technique designating data and an automatic performance data in a sequence memory, and performance technique data which varies in a lapse of time in a performance data memory to reduce the amount of sequence memory. When the performance technique designating data is detected during the performance, the performance technique data corresponding to the detected performance technique designating data is read out. The performance technique data controls musical tones specified by the automatic performance data. Thus, various performance technique can be realized with a small amount of sequence data.

Abstract: A system for use in an electronic musical instrument, which system includes a musical sound generating unit for generating a musical sound, and a detection unit for detecting that the magnitude of the musical sound data generated by the musical sound generating unit exceeds a processing capability, on the basis that the value indicated by the most significant bit prior to data processing not equal to that after data processing. A maintaining unit is also included which forcibly maintain the level of a signal representing the musical sound data at a maximum amplitude thereof, on the basis of the result of the detection effected by detection unit.

Abstract: Waveform data written in a RAM 2 base on write addresses is always read out as two waveform data from two read addresses 1 and 2 designated by a CPU 1, and two interpolation data 1 and 2 are formed. A smaller address difference A between the write address and the read address 1 is multiplied with the interpolation data 1 as an envelope value to obtain cross-fade data 1. Similarly, cross-fade data 2 corresponding to the read address 2 is obtained. The two items of cross-fade data 1 and 2 are added to each other to obtain output waveform data. An envelope value of waveform data near a waveform discontinuous point becomes almost zero, and click noise can be eliminated.

Abstract: A musical tone synthesizing apparatus provides a time-varying signal processing circuit the transfer function of which gradually varies over time in order to gradually vary over time the tone color of a synthesized musical tone. A number of time-varying signal processing circuits are presented. An interpolation-type-time-varying signal processing circuit is provided with interpolators for interpolating control parameters generated based on a desired musical tone, a signal processing circuit carrying out a signal operation based on the interpolated control parameters on an input signal incomming thereto.

Abstract: The repetitive PCM data developing device of this invention extracts segment waveform PCM data which becomes basic structural part of repetitive PCM data from the waveform of PCM data converted from analog sound signal such as a melody and further extracts envelope PCM data showing the shape of envelope curve from the waveform of PCM data. And the envelope PCM data is divided into blocks for every equal part of amplitude, the segment waveform corresponding to the block is selected from the segment waveform PCM data, and the waveform information including the shape of segment waveform, frequency, amplitude and repetitive number is prepared for every block. Lastly, based on the waveform information, the repetitive PCM data having the blocks combined and continued is prepared.

Abstract: An automatic playing apparatus which reads tone information from a ROM piece by piece to play a demonstration. The tone information stored in the ROM includes note data for generation of a musical tone as well as data for changing the parameters of music corresponding to the note data. When a demonstration is played, the note data and the data for changing the music parameters stored in the ROM are read out piece by piece, and the associated musical tones are generated accordingly. In this way, the musical piece being automatically played changes with each repetition, so that listeners hear a different version of the piece each time it is re-played.

Abstract: A tone generating apparatus that employs a read-out system comprises a waveform memory wherein are stored, as waveform data for a transient portion, waveform data that have a weighted attenuation characteristic and that are stored at a predetermined interval within a stationary portion following a rising portion of the musical tone, and waveform data that are obtained by extracting and linking multiple sets of the waveform data at the predetermined interval within a stationary portion, by filtering the resultant waveform data by employing a filtering process that does not alter phase information, by extracting from filtered waveform data waveform data for an interval equivalent to the predetermined interval, by linking together the extracted waveform data in numbers equivalent to the number of waveforms included in the predetermined interval, and by weighting the resultant waveform data with a rising characteristic; and wherein are further stored, as waveform data for a repetitive portion, the filtered wavefo

Abstract: An acoustic data output device comprises an addressable memory for storing acoustic data. A plurality of clock signals are coupled to count separate address counters of a number corresponding to the number of clock signals. A signal selector is responsive to the clock signals for providing an address counter selection signal, whereby at any given time the selection signal corresponds to a separate one of the address counters. An addressing device is responsive to the address counter selection signal for selectively addressing the addressable memory with the count of the corresponding address counter. A separate data latch corresponds to each address counter and the data latches are coupled to receive the output of said addressable memory. The outputs of the data latches are synchronized with the clock signal corresponding thereto.

Abstract: A method for modelling time variant signals and multiple tone generating apparatus for a real time controllable, time variant waveform synthesizer. Speech or musical tone generation is accomplished by storing a DSQ (Demodulated Segment Quantization) codebook representation of a time variant signal. A DSQ codebook is a parametric representation of a time variant signal, wherein a signal's parameters are a time variant amplitude data sequence, a time variant pitch (advance/delay operator) data sequence, and a data sequence corresponding to a set of invariant waveshapes and their corresponding duration values. A signal is reconstructed by concatenating periodic segments of finite duration and, scaling its amplitude via a time variant amplitude data sequence and altering pitch or harmonic content via a time variant pitch data sequence. A plurality of unique DSQ codebooks and tone generators are assigned to a plurality of key actuations for multi-timbral operation.

Abstract: Data compression apparatus and corresponding method used for decaying musical instrument sounds in a digital sampling instrument. The data compression technique according to the present invention provides for data compression of decaying musical instrument sounds that is designed to be stored in a small space, provide for adequate musical reproduction of the sound, and be reproduced using current data sample playback technology.

Abstract: An electronic musical instrument for generating musical tone signal including a performance data generating part or generating performance data such as key-on, key-code and key-touch. The instrument also includes a control circuit for generating musical tone control data such as envelope rate data, envelope level data and initial phase data according to the performance data. Further, the control circuit adopts the time-sharing technology for generating plural musical tone signal, so that this instrument is comparatively simple at its circuit configuration compared with the prior art.

Abstract: An envelope shape generation device includes an envelope shape memory storing envelope shape data, a touch information generation circuit for generating touch information, an envelope shape data reading circuit for reading out the envelope shape data prestored in the envelope shape memory in response to the touch information to form an envelope shape signal.

Abstract: A tone generating apparatus which comprises a wave memory in which first tone waveform data with a preselected length extracted from an attack portion of a musical tone and second tone waveform data with a preselected length following the first tone waveform data and having a value of zero are stored. A read circuit reads the first tone waveform data only once from the wave memory and subsequently reads the second tone waveform data repeatedly. A tone generator generates a musical tone based on the tone waveform data read out by the read circuit. In reading out tone waveform data from the wave memory, the first tone waveform data is read out first, followed by repetitive reading of only the second tone waveform data.Repetitive reading of the second tone waveform data produces no sound because the contents of the second tone waveform data are zero. Thus, this system performs a function equivalent to tone release effected by reading out a one-shot waveform.

Abstract: An electronic musical instrument provides plural channels from which manual-performance sounds and/or automatic-performance sounds (e.g., automatic-accompaniment sounds) are generated. Herein, the manual-performance sound is designated by a performance manually made by a performer, while the automatic-performance sound is designated on the basis of automatic-performance information which is stored in a memory or the like in advance. Normally, a new musical tone is assigned to an unoccupied channel which is not occupied with a tone generation, so that the new musical tone will be generated from the unoccupied channel. However, under a full-channel condition where all of the channels are occupied with the tone generation, a new manual-performance sound is assigned to one of the channels whose envelope value is the smallest.

Abstract: When a new tone is to be assigned to a certain channel, an amplitude level of a preceding tone signal which is being produced in this channel is detected and a damp rate is determined on the basis of the detected amplitude level. Tone volume of the preceding tone signal is rapidly attenuated in accordance with the damp rate thus determined and, thereafter, generation of a new tone signal is started. The damp rate thereby is variably controlled in accordance with the magnitude of tone volume level of the preceding tone signal during a damp control and both optimum prevention of a click noise and a very quick rapid attenuation control corresponding to the tone volume level can be realized. The invention is applicable not only to a damp control of tone volume of a tone but also to a damp control of an envelope shape signal used for other control purposes.

Abstract: The present invention relates to an envelope signal generator for electronic musical instruments, and more particularly to an envelope signal generator that generates natural envelopes from which digital noises are removed substantially by obtaining a difference between a current value and a targeted value and then generating a corresponding value for compensating the difference.

Abstract: A parameter signal generator including a parameter generating information storing unit for storing parameter generating information necessary for generating a parameter signal, and a parameter signal generating unit for generating a parameter signal. The parameter generating information is serially read from the parameter generating information storing unit and the thus-read parameter generating information is preset in a parameter signal generating unit other than the parameter generating information storing unit. Therefore, the parameter signal generator includes a storing unit other than the parameter signal generating unit, and accordingly, a general-use memory can be employed as the storing unit, to substantially lower cost. The processing of generating and radiating musical sounds can be performed at a practically required speed by employing a high speed processor as a central processing unit.

Abstract: An envelope waveform generation apparatus which generates an envelope waveform consisting of a plurality of segments in order to control a musical tone signal, having a touch data detection device, which detects touch data corresponding to the relative strength of a generated musical tone, a memory device, which stores a plurality of control mode patterns comprising data showing whether each segment of this envelope waveform is to be controlled by means of this touch data, a selection device, which selects from among the plurality of control mode patterns stored in the memory device, and a touch data supplementing device, which controls each segment of the envelope waveform by means of the touch data, when the data in the control mode pattern selected by the selection device show the each segment is to be controlled.

Abstract: An envelope waveform generation apparatus comprises an envelope waveform signal generator for forming an envelope waveform signal, a specific position setting member for setting a specific position, a position comparator and a key OFF controller. When a key OFF event is detected, the position comparator compares a position and/or level on the envelope waveform with those of the specific position, and the key OFF controller decays the level of the envelope waveform signal in the shape of a predetermined key OFF waveform, or delays key OFF processing by the envelope waveform signal generator on the basis of the comparison result.

Abstract: An electronic musical instrument including a keyboard, a CPU and a sound source. The keyboard designates a pitch of a musical tone. The CPU detects common pitch data of one of predetermined series of pitch data or interval between predetermined two pitches, when a plurality of pitches are designated by the keyboard. The predetermined series of pitch data are stored in a memory in units of pitches which can be designated by the keyboard. The sound source outputs a musical tone signal having a pitch designated by the keyboard and musical tone signals having pitches indicated by the common pitch data detected by the CPU or having pitches corresponding to the interval detected by the CPU.

Abstract: An object of the present invention is to provide an electronic musical instrument which can generate a plurality of tones in spite of the inexpensive and simple structure thereof and can correct the quantity of phase delay of a closed loop in a physical model tone generator without use of any special processor such as a high-speed CPU or a dedicated numerical operation processor, not only to thereby attain performance effects of echo, chorus and the like but to simulate a performance style of repeating the operation of one string or key in the condition in which a tone corresponding to the string or key remains, without production of noise even when parameters for constituent elements of the physical model tone generator are respectively changed widely. The electronic musical instrument includes a driving waveform for storing a plurality of driving waveform data corresponding to performance information in advance, and a closed loop constituted by a shift register and a low-pass filter.

Abstract: An envelope generating apparatus comprises a work memory, a buffer memory, an envelope generator, a writing circuit, and an end signal generator. The work memory stores parameters including a target level LV and an envelope speed parameter SP for generating an envelope signal of a predetermined phase. The buffer memory stores parameters including a target level LV and an envelope speed parameter SP for generating an envelope signal of a phase following the predetermined phase. The envelope generator generates an envelope signal based on the parameters stored in the work memory. When the envelope generator completes the generation of the envelope signal of a predetermined phase based on the parameters stored in the work memory, the writing circuit writes the content of the buffer memory into the work memory.

Abstract: Changes in vibratory position of a batter head of a percussion are detected to output a decay vibration waveform by a detector. A tone source controller sequentially generates a plurality of tone source control codes on the basis of the decay vibration waveform data along time lapse. A tone source circuit controls a reading operation of digital waveform data of percussion tones stored in a waveform memory, and modification of readout data on the basis of the tone source control codes, to generate a tone waveform signal.

Abstract: An electronic keyboard instrument having a performance pad, a detector, a memory, and a sound system. The detector detects a key touch of a key depressed to assign a percussion tone to the pad. The memory stores the key touch detected by the detector with the percussion tone of the depressed key. The sound system produces the stored percussion tone in accordance with the key touch stored in the memory.

Abstract: An electronic keyboard instrument having simultaneous tone channels for generating a plurality of kinds of tones such as percussion tones upon a keyboard operation is disclosed. A memory (17b) stores inherent tone duration values of different kinds of tones to be generated in correspondence with a plurality of keys of a keyboard. A register group (32) for holding tone duration values in correspondence with a plurality of tone channels is arranged. The values held in the register group are decreased by a subtracter (33) along with an elapse of time. Upon a key-ON event, a detector (34) detects the minimum value of the tone duration values held in the register group. A channel corresponding to the register which holds the minimum value is assigned as a new tone channel, and the content of the register is updated with the fixed tone duration value stored in the memory. The updated register renews assignment of a tone channel in a tone source.

Abstract: A system and method for detecting, separating and recording the individual voices in a musical composition performed by a plurality of instruments. The electrical waveform signal for the multi-voiced musical composition is fed to a waveform signal converter to convert the waveform signal to a frequency spectrum representation. The frequency spectrum representation is fed to a frequency spectrum comparator where it is compared to predetermined steady-state frequency spectrum representations for a particular musical instrument. Upon detecting the presence of a frequency spectrum representation corresponding to a predetermined steady-state frequency spectrum representation, the detected frequency spectrum representation and measured growth and decay frequency spectrum representations are fed to a waveform envelope comparator and compared to predetermined waveform envelopes, i.e. frequency spectrum representations during the growth, steady-state and decay periods of the waveform signal.

Abstract: An acoustic signal synthesizer stores a plurality of different acoustic data and includes a separate D-A converter connected to receive each of the different acoustic data. The D-A converters are responsive to separate envelope generators for controlling their respective outputs. A controller controls the output of the acoustic data to the respective D-A converter and simultaneously controls the respective envelope generator output. The output of the converters are mixed.

Abstract: A musical tone generation device comprises a musical tone signal generator and a musical tone control device. The musical tone signal generator consists of an excitation circuit and a delay circuit which simulate the musical tone generation mechanism of a musical instrument. This generator has a hysteresis characteristic, so that the generator generates a musical tone signal having the hysteresis characteristic, in accordance with a musical tone control signal. While, the musical tone control device converts the musical tone control signal into other musical tone control signal which nullifies the hysteresis characteristic of the musical tone signal generator. Therefore, the musical tone signal generator generates musical tone signals without the hysteresis characteristic.

Abstract: A main CPU and a sub CPU take share of executing a tone generating process to generate multiple tone signals on a real-time basis without using an exclusive tone generator. The main CPU and sub CPU are formed on a one-chip LSI, thus facilitating realization of a compact electronic musical instrument. According to another structure, the main CPU executes tone generation while the sub CPU performs an effect process, thereby permitting a one-chip LSI to generate an effect-added musical tone.

Abstract: An envelope extracting circuit extracts an envelope from the waveform sampled by a musical tone sampling circuit, and stores the envelope data into a memory. An envelope approximating circuit approximates the envelope data as stored in the memory by the function data such as linear or exponential function data. The original envelope is approximated by a limited number of function waveforms whose characteristics change at switching points.

Abstract: A method for processing a waveform includes the steps of dividing an original musical tone into head data, mix data, and loop data. The data is subjected to several processing steps, including cross-fade mixing. All processing steps are carried out before the processed waveform is stored in memory. Therefore, when the stored data is read out to reproduce the original musical tone, no interpolation steps are required to link the head, mix, and loop data together because that data has been smoothly linked together prior to storage in the memory. As each musical tone is read out, the head data is read out first, followed by the mix data, and then the loop data is read out in alternating directions. The smoothly linked head, mix, and loop portions of the musical tone provide a pleasing reproduction of the original musical tone.

Abstract: A sound generating device for generating a variety of sounds has a main control circuit which includes a ROM for storing melody data. A sound source is coupled to the control circuit in accordance with sound scale data stored in the ROM. The sound source has a waveform memory for storing a sound waveform in a digital form. The sound waveform memory is read at a frequency corresponding to the sound scale data. An envelope waveform memory stores an envelope waveform in a digital form. A digital to analog conversion circuit converts the digital envelope waveform in accordance with the digital sound waveform to produce an analog voltage.

Abstract: An electronic musical instrument can execute a musical performance with two timbres mixed together by operating a single key, for example. Of the two timbres, a master timbre is set in normal mode and is stored in a first memory, while a slave timbre is selected in tone mix mode and is stored in a second memory. Each timbre can be altered as desired. To alter the master timbre, timbre switches are operated after the mode is temporarily changed to normal mode. To alter the slave timbre, the timbre switches are operated in tone mix mode. When the tone mix mode is set, this electronic musical instrument can permit a player to easily alter tone parameters such as the volume, pitch and attack delay time of each timbre.

Abstract: A musical tone generating apparatus includes a waveform generator for generating a musical tone signal corresponding to a desired musical tone based on a key-on event which occurs in a keyboard and an envelope generator for generating an envelope which controls the amplitude of the musical tone signal in response to the key-on event. When a key-on event occurs, the envelope generator compares the current value of the envelope with a predetermined value, and based on the result of this comparison, determines a initial value of the next envelope corresponding to the key-on event. Consequently, the musical tone generating apparatus can generate musical tones without generating a click noise even if the key-on event repeatedly occurs over time at short intervals.

Abstract: A vibration of a string is picked up by a pickup to be converted to an electric signal. A pitch extracting circuit obtains pitch data expressing a pitch or a duration of the string vibration from the electric signal. A musical tone generating circuit generates a musical tone having a corresponding tone pitch in accordance with the pitch data. An envelope extracting circuit extracts an envelope from the eletric signal detected by the pickup and supplies a signal expressing the envelope to a multiplier. The extracted envelope signal is multiplied to the musical tone signal by a multiplier after a predetermined timing has been past. In other case, the extracted envelope signal is mixed with a synthe-envelope signal at a desired ratio, thereafter the mixed envelope signal is imparted to the musical tone signal by multiplying processing.

Abstract: A musical tone signal generating apparatus provides at least a waveform memory which stores a plurality of fundamental waveform data based on three-dimensional coordinate address system having three coordinate axes to which respective musical tone control parameters are assigned respectively. The desirable fundamental waveform data is read out at an address corresponding to a coordinate position determined by selecting desirable musical tone control parameters. Then, an interpolation operation is carried out on the fundamental waveform data which are sequentially read out so that an interpolated musical tone waveform signal is formed. The waveform of the interpolated musical tone waveform signal is similar to and intermediate to the waveforms of the fundamental waveform data to be synthesized. Thus, the interpolated musical tone waveform signal is converted into a musical tone signal, by which corresponding musical tone is to be sounded.

Abstract: An electroic musical instrument of the present invention is provided with a damper control as well as tone generation instructin device and tone generation device. While the damper control is operated, the tone generation device continues tone generation even if the stop thereof is instructed by the tone generation instruction device. Moreover there is provided pitch control device adapted to change the pitch of the tone currently generated while the damper control is operated.Accordingly, when the damper control is operated, the resulting musical tones can be enhanced in their variety, distinct from normal tone generation. This allows an electronic musical instrument, for example, to generate such sounds as when the damper pedal is stamped with a piano.

Abstract: A differentiation circuit outputs a normalized time variable signal for each phase. This time variable signal is multiplied by a gain parameter by a multiplier, thus reproducing an AC amplitude level lost in normalization. The reproduced output is added to an amplitude parameter by an adder, thus reproducing a DC amplitude level lost in the normalization. A CPU reads out the parameters of the differentiation circuit and adder from an ROM, and writes them into a parameter memory. When phase-change data is detected, the content of the parameter memory is rewritten, thereby forcibly changing the phase.

Abstract: A detector unit is provided which receives envelope signals related to a predetermined number N of channels to detect a channel showing a greatest or smallest level of the envelope signal among the N channels and outputs data indicative of the detected channel and the level of its envelope signal. When the total number M of the channels is larger than N, a plurality of the detector units are provided, the envelope signals of the number M of the channels are divided into groups numbering not more than N, and the groups are distributed to the respective detector units so that the channel of which level of the envelope signal is the greatest or smallest is detected in each of the detector units. The levels of the envelope signals of the channels detected by the respective detector units are compared with each other, and one detector unit connected with the channel of the greatest or smallest level of the envelope signal is identified.

Abstract: A method of performing an operational expression representing an operation on first and second operands used for computing various problem data and information relating to musical tones, the method comprising the step of representing problem data, which are to be processed, by using a representation system by which the first and second operands have the same sign, and by which the value of one of the first and second operands represented by bits having orders higher than those of bits used for representing the other of the operands is reduced by effecting a suppressing operation by using a suppressing parameter having a value larger than the value that can be obtained by the one of the first and second operands represented by the higher-order bits and the value of which is to be reduced, the step of computing mantissa part data of the thus represented problem data in accordance with power part data of the thus represented problem data, and the step of performing an carry operation if a carry is generated in t

Abstract: An electronic musical instrument shaped like an electric guitar sounds individual notes that are synthesized to sound like an electric guitar. These notes may either be selected randomly selected by a player or from segments of prearranged musical tracks. The instrument provides for maintaining the tempo of manually played or preprogrammed notes, synchronizing the transitions between sequentially selected musical tracks, overlaying manual notes on the tracks, and a number of electric guitar-like sound effects including vibrato, chorus, overdrive, slurs and soft picks.