Matsushita Electric Industrial Co., Ltd.

Kinji Kawamoto

Masaru Uya

Kazuhiro Murase

Masao Tsukamoto

Tetsuhiko Kaneaki

Masataka Nikaido

Naoki Ejima

Tatsuya Adachi

Sakurako Matsuda

A data recording apparatus includes a digital input processing circuit, an analog input processing circuit including an A/D converter for recording the analog input signal in digital form, a switch for selecting either digital or analog input signals for recording, and a control circuit. Normally, the apparatus records the digital input signal. When the digital input processing circuit detects a synchronizing error or inhibition of recording the digital input signal (digital copy) by analyzing the sub-code signal of the digital input signal, the control circuit controls the selecting switch so as to select the analog input signal. In order to reduce unnatural level variation due to change of selection between the digital and analog input signals, there are further provided a polarity change circuit, variable delay, and variable gain amplifier for the analog audio signal.

Data recording apparatus

A tone source system for a superior electronic musical instrument suitable for an LSI application in which the wave data can be provided in a time division multiplex form, or the envelope data can be provided in a time division multiplex form in a synchronous relationship with it, and the wave data to which the envelopes are attached can be provided in a time division multiplex form through multiplication of the data.

Electronic musical instrument

A wave generating method and a wave generating apparatus using the method are arranged such that plurality of wave samples, each being generated successively, are respectively weighted by, for example, being multiplied by a plurality of wave functions generated corresponding to the plurality of wave samples. The plurality of weighted wave samples are summed to obtain a desired wave. The kind of each of the plurality of wave samples generated successively is changed at each time when the value of corresponding one of the plurality of wave functions becomes zero. Therefore, the apparatus includes wave generators for generating the wave samples successively, wave function generators for generating the wave functions successively, multipliers for multiplying the wave samples by the wave functions respectively, an adder for adding all of the outputs of the multipliers to generate the desired wave, and a wave changing circuit for changing the kind of each of the wave samples when the corresponding one of the wave functions becomes zero.

Wave generating method and apparatus using same

A multiple wave generator for an electronic musical instrument which has a wave data memory storing plural data samples of a wave shape, a wave address register storing wave address data partially designating sampled data in the wave data memory, a difference address register storing difference address data which specifies incremental address amount, a wave address calculator adding the wave address data to the difference address data and writing into the wave address register, the summed address data being separated into wave memory address data and partial address data, and a wave calculator. The wave memory address data, which are part of the wave address data, are applied to the wave data memory for reading out one data sample, and the one data sample and the partial address data are applied to the wave calculator for calculating interpolated wave sample data corresponding to the wave memory address and the partial address.

Multiple wave generator

A wave reading apparatus includes a wave generator for generating a plurality of wave signals, a read-out frequency generator for generating a plurality of read-out frequencies, a controller for controlling calculation, writing and reading of wave samples, a writing device, a plurality of buffer memories and a plurality of read-out devices. The controller informs requests of wave samples calculation to the wave generator in accordance with the read-out frequencies. The calculated wave samples are written through the writing device to the buffer memories and read out by the read-out device in accordance with the read-out frequencies, at least one of which is different in frequency from the remainder.

Wave reading apparatus

An electronic musical instrument equipped with multiple musical tone signal generating channels, with an automatic play system which controls the tone generation of the musical tone signal generating channels on the basis of the automatic play data recorded in a memory so as to successively and automatically generate musical tones. The instrument also has a manual play system which controls the tone generation of the musical tone signal generating channels by the keyboard and other performance controls so as to generate musical tones by control of the tone generation of the multiple musical tone signal generating channels by the joint use of the automatic play system and the manual play system.

An electronic expression device for producing a tremulant effect. The device has a distributor having one input terminal and a plurality of output terminals, a plurality of transmission channels being connected to the respective output terminals of the distributor, and a coupler for coupling the output signals of the channels. At least one of the channels has a modulator having a characteristic such that at least either the modulation depth or the modulation frequency increases in accordance with an increase in the frequency of the input signal and the modulation depth exceeds .+-. .pi./2 radian for phase modulation and 100% for amplitude modulation in a high frequency range. The distributor can be such as to produce different phase shifting characteristics in the signals at the respective output terminals and the channels can have different phase shifting characteristics from each other for securing a further novel tremulant effect. The audio frequency signal applied to the input terminal of the distributor is translated in such a manner that vectors of the signal are fluctuating differently in frequency, phase and amplitude.

Electronic expression device for producing tremulant effect

Electronic expression device for producing a novel tremulant effect. The device has a frequency range separator separating an audio frequency signal into a plurality of sub-band signals at least one modulation system being connected to the frequency range separator in order to modulate the sub-band signals other than the lowest sub-band signal, and a coupling means for coupling the output signals of the modulation systems and the lowest sub-band signal. Each of the modulation systems has at least one modulator having a characteristic such that at least the modulation depth increases in accordance with an increase in the frequency of the input signal and the modulation depth exceeds .+-..pi./2 radian for phase modulation and 100 percent for amplitude modulation in a high frequency range. The audio frequency signal applied to the input terminal is translated in such a manner that frequency spectra of the signal are fluctuating differently with respect to the frequency, phase and amplitude from each other in high frequency ranges corresponding to the sub-band signals except the lowest, but are not fluctuating in the lowest sub-band frequency range.

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Yahata, Japan

Kinji Kawamoto