Abstract: A computer system and method for performing wavetable music synthesis employing a high priority I/O bus request mechanism to improve the audio fidelity of the system. The system comprises a system memory which stores wavetable data, an I/O bus coupled to the system memory, an I/O bus arbiter coupled to the I/O bus which accommodates normal priority I/O bus requests and high priority I/O bus requests, and a system audio device. The system audio device comprises an I/O bus interface coupled to the I/O bus, a synthesizer coupled to the I/O bus interface, a plurality of buffers coupled to the I/O bus interface and to the synthesizer and a buffer manager coupled to the I/O bus interface, the synthesizer, and the plurality of buffers. The synthesizer generates a request for wavetable data samples. The buffer manager determines if the samples are in the buffers.

Abstract: A musical sound generating apparatus creates a waveform to generate a musical sound according to performance information. In the apparatus, a first waveform generator is operable for creating a waveform. A second waveform generator is operable independently from the first waveform generator for creating a waveform. An input device provides performance information. A designating device designates at least one of the first waveform generator and the second waveform generator in correspondence with the provided performance information. A controller selectively operates the designated one of the first waveform generator and the second waveform generator to create the waveform according to the provided performance information. An output device generates the musical sound based on the created waveform.

Abstract: A method of generating musical tones is provided. Data indicative of waveforms including at least a first predetermined waveform and a second predetermined waveform are stored in a first storage device such as a RAM. Data indicative of the first predetermined waveform and the second predetermined waveform are sequentially read from the first storage device, in response to a tone-generating command. The data indicative of the first predetermined waveform is read from the first storage device and stored in a second storage device, such as a cache memory, which is operable at a higher speed than the first storage device. The data indicative of the first predetermined waveform stored in the second storage device is repeatedly read from the second storage device, following the reading of the data indicative of the first predetermined waveform from the first storage device. Musical tones are generated based on the data read out by the first and second reading steps.

Abstract: A music system has a main system and a subsystem. The subsystem synthesizes musical tones, based on waveform data supplied from a cache memory as a temporary memory device, transfers waveform data stored in the cache memory in predetermined blocks to a tone generator according to progress of musical tone synthesization by the tone generator, sequentially stores next blocks of externally supplied waveform data in the cache memory at areas thereof which have become empty after the data transfer, and mixes together the musical tones synthesized by the tone generator and musical tones supplied from the main system. The main system includes a waveform memory and synthesizes musical tones, based on waveform data supplied from the waveform memory.

Abstract: A method of generating a tone waveform using a CPU is provided which prevents or minimizes operational delays of other software processing that is executed concurrently with tone waveform generating processing on a multitask basis. The CPU collectively calculates 128 (one block of) tone waveform sample values each corresponding to a sampling clock pulse, and transmits the calculated tone waveform sample values to a reproduction section in response to a predetermined calculation triggering clock pulse generated every 128 samples. When sufficient processing capability of the CPU performing the multitask is available for the waveform sample calculation, tone waveform sample values for one or more following blocks are also calculated and stored in a sample buffer in advance. When the CPU is too busy with the other software processing to execute the waveform sample calculation, it is just sufficient that the previously stored tone waveform sample values be read out to be transmitted to the reproduction section.

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: A computer system and method for performing wavetable music synthesis which uses system memory to store wavetable data and minimizes audio infidelity introduced by wavetable data access latency. The system comprises a system memory which stores wavetable data, an I/O bus coupled to the system memory, and a system audio device. The system audio device comprises an I/O bus interface coupled to the I/O bus, a synthesizer which generates sounds in response to the wavetable data, a plurality of buffers coupled to the I/O bus interface and to the synthesizer for buffering the wavetable data from the system memory, and a buffer manager coupled to the I/O bus interface, the synthesizer, and the plurality of buffers. The buffer manager manages transfers of the wavetable data from the system memory to the buffers and from the buffers to the synthesizer. The synthesizer generates a request to the buffer manager for wavetable data samples.

Abstract: In a musical tone generator 6 having a waveform memory 8, and an interpolatory calculation circuit 21 for performing an interpolatory calculation on the basis of the plurality of sample values, there are provided a second waveform memory in which the sample values necessary for the interpolatory calculation at the beginning of tone generating are stored, and a transfer circuit for reading out the sample values from the second waveform memory at the beginning of tone generating, and writing them into the interpolation means.

Abstract: An electronic musical instrument stores a plurality of waveform samples. A predetermined number of waveform samples are selected from the plurality of waveform samples. Pitch information for designating a pitch within a predetermined tone range is generated. In response to instructions for automatic assignment of waveform samples, partial tone ranges equal in number to the predetermined number are set within the predetermined tone range, and the predetermined number of the waveform samples selected are assigned to the partial tone ranges, respectively. In response to the pitch information, a partial tone range to which the pitch information belongs is detected from the partial tone ranges. A waveform sample assigned to the detected partial tone range is read. A musical tone is generated based on the read waveform sample.

Abstract: The method of the present invention preferably receives a predetermined number of input values or data from which it may be determined which one of a predetermined number of modulator waveforms is selected and which one of a predetermined number of carrier waveforms is selected for a desired audio signal, musical sound or tone. A portion of the input values are used to generate predetermined control signals which are used in combination with the selected modulation waveform to interpolate stored modulator harmonic spectral values to determine the modulator waveform's harmonic sideband(s). A second portion of the control values that have been generated are used in combination with the selected carrier waveform to then determine the carrier waveform's spectral values, amplitude and envelope amplitude. Following this the carrier and modulator spectral values are combined in a preselected manner to provide an appropriate composite signal.

Abstract: Methods and systems for encoding an audio signal into a bit stream, and for recreating the audio signal from the bit stream are disclosed. In an embodiment of an encoder, a first encoder (10) symbolically encodes a substantially vocal audio signal to form a first encoded signal. A second encoder (12) symbolically encodes a substantially nonvocal audio signal to form a second encoded signal. A multiplexer (14) multiplexes the first encoded signal and the second encoded signal to form the bit stream. In an embodiment of a decoder, a demultiplexer (80) extracts an encoded vocal signal and an encoded nonvocal signal from the bit stream. A first decoder (82) forms a decoded vocal signal based upon the encoded vocal signal. A second decoder (84) forms a decoded nonvocal signal based upon the encoded nonvocal signal. A mixer (86) combines the decoded vocal signal with the decoded nonvocal signal to form the audio signal.

Abstract: A tone generator has a waveform memory which stores waveform data at least having a loop section defined by a loop start address and a loop end address for repetitive reading out. An address-generating circuit generates a readout address by which the waveform data is read out from the waveform memory and delivers the readout address to the waveform memory to read out the waveform data from the waveform memory. A bit mask circuit masks a predetermined range of more significant bits of the readout address to generate a bit-masked address value. When it is determined that the readout address falls outside the loop section at least at one side of the loop start address and the loop end address of the loop section, a looping readout address generated by the use of the bit-masked address value is delivered as the readout address.

Abstract: A digital wavetable audio synthesizer with an LFO generator is described. The synthesizer can generate up to 32 high-quality audio digital signals or voices, including delay-based effects. The synthesizer includes an address generator which has several modes of addressing wavetable data. The address generator's addressing rate controls the pitch of the synthesizer's output signal. A synthesizer volume generator, which has several modes of controlling the volume, adds envelope, right offset, left offset, and effects volume to the data. The synthesizer LFO generator can add LFO variation to: (i) the wavetable data addressing rate, for creating a vibrato effect; and (ii) a voice's volume, for creating a tremolo effect. The LFO generator assigns two triangular-wave LFOs to each of the 32 possible voices. One LFO is dedicated to vibrato (frequency modulation) effects and the other to tremolo (amplitude modulation) effects. It is possible to ramp the depth of each LFO into and out of a programmable maximum.

Abstract: A record and reproduction controlling device is connected to a hard disk memory via a bus. This controlling device receives from a computer information necessary for read/write operation, on the basis of which the controlling device performs its own process to write to or read from the hard disk. The record and reproduction controlling device temporarily stores tone data read out from the hard disk memory into a first buffer memory and then transfers the tone data from the first buffer memory to a second buffer memory. The tone data thus stored in the second memory is then read out at a predetermined readout rate to reproduce a musical sound. It is possible to select either a first reproduction mode for reproducing a data file having tone data of plural channels recorded in an interleaved state, or a second reproduction mode for permitting a simultaneous reproduction of plural data files each having not-interleaved tone data recorded therein.

Abstract: A method is disclosed of modification of parameters of audio signals by dividing a digital signal converted from an original analog signal into sound frames, modifying a pitch and a playing rate of the digital signal within a frame and subsequent successive splicing a last modified frame with a first non-modified frame and calculating a differential mean absolute error to define the best splicing point in terms of producing minimal or no audible noise such that various sections of sound signals can be spliced together to achieve pitch and playing rate modification. An apparatus is also disclosed for implementing the method, the apparatus comprising input and output amplifiers, a low pass filter at the input and a low pass filter at the output, analog-to-digital and digital-to-analog converters, and a pitch shifting processor.

Abstract: An apparatus for processing the speech information includes a first execution device and a second execution device for executing operations at respective different execution cycles, and a first memory unit for reading and recording the speech information. The first execution device and the second execution device exploit the first memory unit in common for processing the speech information. The processing apparatus further includes a second memory unit for storage of the speech information from the first execution device or the speech information read out from the first memory unit. The first execution device records the speech information on or reads the speech information from the second memory unit during the execution cycle of the first execution device. The second execution device accesses the first memory unit during the execution cycle of the second execution device for outputting the speech information to outside.

Abstract: A musical sound generating device has a waveform memory to store musical sound waveform data to be read-out repeatedly between a loop-top address (integral address) and a loop-end address (integral address). The same musical sound waveform data is stored at the loop-top address and the loop-end address. An address computing circuit computes a read-out address, including a decimal part, to repeatedly read out the musical sound waveform data stored between the loop-top address and the loop-end address in the waveform memory. An interpolating circuit carries out interpolation if the read-out address generated by the address computing circuit includes a decimal part. Interpolation is carried out by dividing in proportion the musical sound waveform data read out from the waveform memory using an integral part of the read-out address and the musical sound waveform data read out from the waveform memory using a value obtained by adding 1 to the integral part of the read-out address according to the decimal part.

Abstract: An electronic musical instrument has a waveform memory, a CPU, a tone generator and a keyboard. The waveform memory stores a plurality of waveforms corresponding to musical parameters such as tone colors. The CPU controls the tone generator to generate musical tone signals in response to key-on and key-off events detected from the keyboard. The CPU detects legato performance when a plurality of keys of the keyboard are consecutively depressed and a key-on event is detected prior to a key-off event of the other key which has been previously depressed. When the legato performance is detected, under the control of the CPU, the waveform data except for the attack portion of the waveform are read out from the waveform memory in response to the key-on events which follow the first key-on event, and the musical tone signals are generated by the tone generator based on the read out waveform data.

Abstract: A tone generator (501) for a musical synthesizer has digital waveform generators (602,603) arranged such that a proportion of an output from a waveform generator (602) is supplied to a phase modulating input of a next waveform generator (603), wherein a proportion of the output from the last waveform generator in a chain (603) of serially connected waveform generators is supplied to a phase modulating input of the first waveform generator (602) in said chain, thereby providing a degree of recursion. Outputs from a plurality of waveform generators are supplied to a ring modulator (604) for generating harmonic sums and differences of frequencies produced by said recursion. A variable precision waveform lookup table (803) may be used to select a particular harmonic characteristic of tone and a frequency doubler (1001) may be included in the feedback loop to enable tones containing predominantly odd harmonics to be generated.

Abstract: In the waveform processing apparatus of the present invention, an original sound signal is divided into a plurality of bands, parameters such as amplitude and frequency are extracted for each band, and correction is made so that the amount of deviation of the parameters from the mean value thereof is gradually decreased to zero from a certain time to the time when the repetition period begins, whereby a musical tone signal is re-synthesized based on the corrected parameters. The electronic musical instrument which stores the waveforms processed by the apparatus of the present invention generates musical tones having more natural tone color change.

Abstract: A memory control apparatus that compresses the time widths of time slots of addresses sequentially outputted from a data processing unit so as to access a memory. Readout data is transferred to the data processing unit while expanding the time slot. In a vacant time formed by compressing the time widths of the time slots of the addresses from the data processing unit, refresh processing or hard disk transfer processing is executed. The time widths of the time slots of addresses sequentially outputted from a CPU are compressed so as to write data in the memory, and parallel to this operation, refresh processing can be executed in a vacant time. The memory control apparatus is suitably used in accesses of waveform data between a tone generator system and a waveform memory. Waveform data supplied from another unit can be written in the waveform memory parallel to tone generation using all tone generation channels of the tone generator system for tone generation.

Abstract: A waveform generating apparatus for generating waveforms which can be suitably employed in electronic musical instruments. The waveform generating apparatus calculates and generates regenerated sample data of a regenerated waveform having a desired pitch in synchronization with a constant regeneration sampling interval based on basic sample data which are sampled from a basic waveform by a predetermined basic sampling interval. The apparatus includes a phase generator, an operation mode control circuit and an interpolating circuit. The phase generator generates phase data which designates a phase of basic waveform. The operation mode control circuit supplies a calculation designating data. The interpolating circuit calculates regenerated sample data on the basis of basic sample data and phase data. Wherein, the method of the interpolation which is performed by the interpolating circuit is altered in response to calculation designating data.

Abstract: In the sound source system, the waveform sampled from the sounds of keys pressed down with two or more kinds of intensity are synthesized in a specified rate, thereby forming the waveform of the sounds of keys pressed down with the other kind of intensity. Thus, almost the actual instrumental deep sounds can be reproduced. The sound waveform sampled from weak key presses is passed through a low pass filter, and the filtered waveform composed only of low order harmonic components is transformed to weak press data in the pulse code modulation system for the storage. Similarly, the sound waveform sampled from strong key presses are passed through a high pass filter, thereby removing the low order harmonic components. The filtered waveform composed only of the high order harmonic components are transformed to strong press data in the pulse code modulation system for the storage. The high pass filter can remove the frequency components which pass through the low pass filter.

Abstract: A record and reproduction controlling device is connected to a hard disk memory via a bus. This controlling device receives from a computer information necessary for read/write operation, on the basis of which the controlling device performs its own process to write to or read from the hard disk. The record and reproduction controlling device temporarily stores tone data read out from the hard disk memory into a first buffer memory and then transfers the tone data from the first buffer memory to a second buffer memory. The tone data thus stored in the second memory is then read out at a predetermined readout rate to reproduce a musical sound. It is possible to select either a first reproduction mode for reproducing a data file having tone data of plural channels recorded in an interleaved state, or a second reproduction mode for permitting a simultaneous reproduction of plural data files each having not-interleaved tone data recorded therein.

Abstract: A record and reproduction controlling device is connected to a hard disk memory via a bus. This controlling device receives from a computer information necessary for read/write operation, on the basis of which the controlling device performs its own process to write to or read from the hard disk. The record and reproduction controlling device temporarily stores tone data read out from the hard disk memory into a first buffer memory and then transfers the tone data from the first buffer memory to a second buffer memory. The tone data thus stored in the second memory is then read out at a predetermined readout rate to reproduce a musical sound. It is possible to select either a first reproduction mode for reproducing a data file having tone data of plural channels recorded in an interleaved state, or a second reproduction mode for permitting a simultaneous reproduction of plural data files each having not-interleaved tone data recorded therein.

Abstract: A pitch control apparatus which suppresses the occurrence of a tremolo tone which the interval control is performed. Input audio signal data is written at a memory position at a designated writing address in a memory in a predetermined order for every sampling cycle, a plurality of reading addresses of the memory are designated for every sampling cycle, and are set in a different order from the predetermined order for each cycle which is a multiple of the sampling cycle by a predetermined multiplier, data is read from memory positions of designated plurality of reading addresses in the memory, a coefficient is set in accordance with an address interval between the writing address and each of the designated plurality of reading addresses in the memory, the data read out at the plurality of reading addresses are multiplied by the associated coefficients, and the results are added together as output data.

Abstract: An audio signal processor capable of both sampling and audio processing external audio signals is disclosed. The audio signal processor can sample an audio signal and store it in a fixed store in a two function memory for later playback or manipulation. The processor can also audio process external signals in real time by splitting an incoming signal into two parts; processing one part such that it is time delayed and/or pitch shifted, or both, with respect to the unaltered part; and recombining the processed part and the unaltered part to achieve time delay effects such as flanging, chorus and echo. Moreover, the audio signal processor can output samples from the fixed store and real time processed signals simultaneously to achieve complex sound combinations and auditory effects.

Abstract: A musical tone forming apparatus employed by an electronic musical instrument, comprises an external storage unit, a transfer DMA, a waveform RAM and a sound-source circuit. The external storage unit stores data representing a waveform of a musical tone, wherein the waveform comprises an attack portion and its remaining portion. The waveform RAM provides an attack-waveform storage area, exclusively used for storing attack-waveform data representing the attack portion, and a buffer storage area exclusively used for storing other waveform data representing the remaining portion. Before the production of the musical tone, the transfer DMA transfers the attack-waveform data to the waveform RAM, so that the attack-waveform data is stored in the attack-waveform storage area in advance.

Abstract: In an electronic instrument, sound waveform is compressed for efficient storage, while quick response from the depressing of keys till the sounding is assured. The electronic instrument is provided with the waveform ROM for storing the waveform of the start of sounding without compressing. The subsequent waveform is compressed and stored in the waveform ROM. The sound source system having a waveform reproducing portion is also provided for developing the compressed stored waveform. The electronic instrument is further provided with a waveform RAM for temporarily storing the waveform developed by the waveform reproducing portion. When the keys of the electronic instrument are depressed, sounds are generated at first based on the uncompressed waveform data, and the compressed waveform data is concurrently developed in the waveform RAM. After all the uncompressed waveform data is read from the waveform ROM, sounds are subsequently generated based on the waveform data developed by the waveform RAM.

Abstract: In a loop circuit having a low-pass filter, a delay circuit, and an all-pass filter, a wave signal read from a wave memory is supplied as an excitation signal to the loop circuit and circulated therein to synthesize a musical tone signal. A musical tone signal to be synthesized and processed by a signal processing system having a characteristic inverse to the loop circuit is stored in the wave memory.

Abstract: A musical sound signal recording/reproducing apparatus, which records/reproduces a musical sound signal having a waveform, includes a rewritable waveform memory and an address translator. The rewritable waveform memory stores waveform data of musical sound signals. The rewritable waveform memory is accessed with real addresses to write, read, delete, and edit the waveform data. The address translator translates consecutive virtual addresses supplied thereto into the real addresses. Therefore, the apparatus accesses the rewritable waveform memory with consecutive virtual addresses instead of the real addresses which are consecutively or discretely arranged.

Abstract: A memory stores waveform sample data for plural sample points forming a given tone waveform, and one of the stored waveform sample data stored for every two adjacent sample points is expressed in PCM representation while the other is in difference value representation that is based on the PCM values stored for two sample points on both sides of the sample point of the other sample data. The number of bits in each address of the memory is greater than the number of bits in each of the PCM data, and each of the PCM data is stored at some bit positions of one address, while the difference value data is stored at the remaining bit positions of one or more addresses.

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 tone signal generating apparatus, including a memory for storing wave data containing frequency components within a full band; a tone generator for reading the wave data from the memory in accordance with key ON/OFF data to generate a tone signal; a velocity generator for generating a velocity value based on key ON/OFF data; a first coefficient processor for producing a first coefficient to control the amplitude in accordance with the velocity value generated by the velocity generator; a first operator for performing an operation on the first coefficient produced by the first coefficient processor and the tone signal generated by the tone generator, a filter for extracting frequency components within a specific band from the tone signal output from the first operator to produce a first tone signal and outputting the first tone signal; a second coefficient processor for producing a second coefficient to control the amplitude in accordance with the velocity value generated by the velocity generator; and a sec

Abstract: A waveform memory for storing data of musical tone waveforms can be mounted in and dismounted from an electronic musical instrument body. The waveform memory is thus replaceable, permitting the sounding of tones with various varieties. In addition, if musical tone waveform data corresponding to a tone designated for sounding is not stored in the memory, it is automatically loaded in the memory, thus permitting automatic sounding of tones to be requested.

Abstract: The position of a connecting portion between waveforms can be arbitrarily set when a plurality of waveform data is obtained by changing pitch widths of stored external sound waveform data, when a read rate of the waveform data is increased or decreased and the readout waveform data is synthesized, or when the waveform is changed from one waveform to another waveform. In addition, a plurality of loop reproduction cycles can be arbitrarily set when the waveform data is to be read out. In loop reproduction, two items of waveform data having different phases between the preset start and end addresses can be repeatedly read out and synthesized, and their mixing ratios can be changed as a function of time, thereby performing loop reproduction so as not to abruptly change amplitude values of the waveforms.

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 sound processing system comprises a waveform distributor for distributing an input sound waveform, offset devices for executing an offset process for each of the waveforms received from the waveform distribution device, and a multiplication and addition device for multiplying the offset waveforms by predetermined coefficients and then adding the multiplied waveforms. Since the distributed waveforms are offset by the independent offset devices, highly varied sound can be produced by changing the coefficients of the offset devices and the multiplication and addition device, and also by changing these coefficients as time elapses.

Abstract: A digital audio signal prerecorded in a DAT is processed by a computer to calculate a compressed difference data array. This compressed difference data array is obtained by compression processing on the basis of a variable compression ratio depending on the magnitude of the variation of the original waveform data array. This compressed difference data array is written in a ROM as waveform data for musical tone generation, and the ROM which stores the waveform data is used as a circuit arrangement for an electronic musical instrument. The electronic musical instrument expands the compressed difference data array on the basis of expansion ratio data, and reproduces it as a waveform data array. This waveform data array is audibly output as a musical tone signal.

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: A digital sampling instrument is disclosed. The instrument provides the capability of accessing and outputting stored digital data within a single clock cycle. The instrument also provides improved volume scaling for sound generation and further eliminates redundant loading of a particular sound into a sound memory.

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: An electronic musical instrument utilizes a memory unit containing sampled values of waveforms stored in separately addressable memory locations. A first waveform address bus and a second waveform data bus are both connected to the unit. A counter is connected at its output to the first bus and is connected at its input to both a third address bus and a fourth system data bus. Sampled values of waveforms are supplied to the third and fourth buses. Waveform data is read out of the second bus. An arrangement including a central processing unit, a random access memory and a read only memory is connected to the third and fourth buses. This arrangement together with the counter determines, according to the stored sampled values, the sequence in which the individual memory locations and the sound information stored in the locations should be read.

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: A tone generating apparatus comprises a wave memory for consecutively storing first tone wave data acquired by performing pulse code modulation on a tone waveform in a first predetermined interval starting at an attack of a musical tone, second tone wave data provided by adding that tone wave data which is obtained by performing pulse code modulation on a tone waveform in a second predetermined interval following the first predetermined interval and is then weighted with a fade-out characteristic and that tone wave data which is acquired by synthesizing waveform components of a tone waveform in a third predetermined interval following the second predetermined interval and is then weighted with a face in-characteristic after being linked for the second predetermined interval, and third tone wave data produced by synthesizing waveform components of a tone waveform in a third predetermined interval following the second predetermined interval based on a characteristic of the tone waveform in the third predetermin

Abstract: A single signal processor performs a pitch process which produces musical sound waveform data having a frequency corresponding to received pitch data, a filtering process for filtering the generated musical sound waveform data, and an amplitude process which controls the amplitude of a musical sound generated on the basis of the filtered musical sound waveform data in order to produce a musical sound. It simultaneously performs outputting the produced musical sound waveform data to a plurality of output terminals and an effect process which imparts an effect to the musical sound data. The signal processor outputs at least one of musical sound waveform data to which the effect is imparted and musical sound waveform data to which no effects are imparted, using at least one of an external and an internal effect circuit to thereby impart a variety of effects to the resulting musical sound.

Abstract: The position of a connecting portion between waveforms can be arbitrarily set when a plurality of waveform data is obtained by changing pitch widths of stored external sound waveform data, when a read rate of the waveform data is increased or decreased and the readout waveform data is synthesized, or when the waveform is changed from one waveform to another waveform. In addition, a plurality of loop reproduction cycles can be arbitrarily set when the waveform data is to be read out. In loop reproduction, two items of waveform data having different phases between the preset start and end addresses can be repeatedly read out and synthesized, and their mixing ratios can be changed as a function of time, thereby performing loop reproduction so as not to abruptly change amplitude values of the waveforms.

Abstract: A tone generator comprises a basic wave memory for storing a first basic wave data of a musical tone signal, a differential wave memory for storing differential wave data between the first basic wave data and a second basic wave data which is different form the first basic wave data, and mixing device for mixing the first basic wave data and the differential wave data. The musical tone signal is produced by using the mixing device which mixes the basic wave data and the differential wave data without using directly stored sampling data memory. Further a multiplier for multiplying said differential wave data by random factors is provided, the random factors being distributed with normalized probability, resulting in that wave data not only varying tone color at random, but also resembling as a whole the basic wave tone color can be obtained.

Abstract: A device for generating a waveform of a musical tone, which comprises a waveform data memory for storing data representing the waveforms of a plurality of musical tones, a waveform data selector for selecting any combination of more than two waveform data stored in the waveform data memory, a sound emission instructing unit for issuing an instruction for emitting a musical tone, a waveform data reading unit for reading out the waveform data selected by the waveform data selector from the waveform data memory in a reading step of a processing program common to the musical tones, in response to an instruction issued by the sound emission instructing unit by effecting a time sharing processing, and a synthesizing unit for accumulating and synthesizing the waveform data read out by the waveform data reading unit.

Abstract: A waveform data storing unit stores waveform data only at steps midway among a top zero level step and originally sampled steps at every sampling period from the top zero level step. An output means is included for outputting the waveform data at a moment staggered from another moment, at which the waveform data at the top zero level step and the originally sampled steps are ordinarily read out, by a period of time corresponding to half a step. The occurrence of a difference in phase of the read-out waveform is prevented without the need of a data correction unit. The waveform data storing unit stores midway-step data which are averages of waveform data at adjoining originally sampled steps and difference data representing the difference between the waveform data at the originally sampled steps and the midway-step data. A fine waveform can therefore be obtained while using a smaller quantity of data.