Casio Computer Co., Ltd.

Terumo Kabushiki Kaisha

Kohtaro Hanzawa

Hiroyuki Sasaki

Shigenori Morikawa

Hiroshi Morokuma

Kazuhisa Nakamura

Kikuji Tanaka

Goro Sakata

Masatoshi Watanuki

Jun Yoshino

Toshiaki Kawanishi

Kunihiro Sugita

Ryutaro Hayashi

Shiro Ishiguro

Keiichi Sakurai

Hideaki Ishida

Shigenori Sano

An electronic musical instrument comprises a tone generator for generating a plurality of different digital waveform signals corresponding to different timbres, and a device for setting a plurality of ranges defined by two parameters, a first one of the parameters being a pitch parameter and a second one of the parameters being a key touch parameter. The parameters vary according to the musical performance, and a range for the pitch parameter in combination with a range for the key touch parameter respectively designating one of the plurality of different digital waveform signals having different timbres. An input device is provided for inputting the two parameters according to a musical performance. A judging device judges a respective range to which each of the inputted two parameters belongs, and a selector selects one of the plurality of digital waveform signals from the setting device corresponding to a judged result to generate one of the plurality of different digital waveform signals from the tone generator, the plurality of different digital waveform signals thereby being selectively generated in order to output a sound having a corresponding timbre in response to the two parameters thus inputted.

Tone information processing device for an electronic musical instrument

In a signal processing apparatus which stores a program inside, and performs a series of processes on a received signal according to the program, such as an arithmetic operation or a delay process, and outputs the processed signal, for rewriting the program in order to change the contents of the processing. Program data is prevented from being output in synchronism with a sampling clock generated at the timing of an input signal. This design can minimize noise occurring due to a change in the algorithm of the signal processing during signal processing. Further, in the case where a program for a separate signal processing circuit is rewritten in response to an instruction that is given from outside at an arbitrary timing, noise can also be minimized by proceeding with the rewriting in synchronism with a sampling clock.

Signal processing apparatus

When a plurality of effects are simultaneously applied to an input audio signal, a plurality of effect-algorithms each for applying solely an effect to the input signal are stored in a memory, and a plurality of combination-algorithms or combination-data which represent combinations of the effects and orders in which effects are applied to the input audio signal are stored in the memory. When one of the combination-algorithms or the combination-data is selected, effect-algorithms included in the selected combination-algorithm or combination-data are selectively read out from the memory. A program for applying effects in a predetermined combination and order is written by CPU based on the read out effect-algorithms and combination-algorithm or combination-data. Receiving the program, DSP successively applies effects to the input audio signal in accordance with the program. As a result, the present effector needs less memory capacity than the conventional effector in which a number of programs consisting of combinations of effect-algorithms are previously stored. A multi-effector comprised of a connection of a digital effect adding device and an analog effect adding device, is provided with a memory having a plurality of memory areas for storing audio signals. An input audio signal, an input signal to the analog effect adding device and an output signal of the digital effect adding device are stored in respective memory areas of the memory. Whether either of input signals is supplied to the digital effect adding device or whether the output signal of the digital effect adding device is input to the analog effect adding device or the output signal is output as a final signal are decided by operation of an externally operated switch. In this way, the order in which effects are applied can be altered independently of the connection of the above two effect adding devices.

Effect adding apparatus

A signal processing apparatus according to the present invention is used as a sound source, an effecting machine and/or a communication equipment, which simultaneously generates or processes a plurality of musical tones and sounds on the basis of a plurality of input data such as performance data, musical tone data and/or communication data. This signal processing apparatus stores a program prepared for controlling operation to generate or process musical tones and sounds only for one channel. The program is read out in accordance with a lower bit of a readout counter. A upper bit of the readout counter is used to designate a channel to which the generated or processed musical tones and sounds are assigned in accordance with the read out program. As a result, only a small area is required for storing the program and a simple construction may be employed in the apparatus.

Signal processing apparatus for repeatedly performing a same processing

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.

Waveform signal generating apparatus and method for waveform editing

A plurality of groups of tone parameters different in kind required for the generation of a musical sound is stored. The tone parameters of the same kind among those tone parameters are modulated with the same sway signal generated at the same time at a desired time or at fixed intervals of time when a key concerned is depressed. The modulated parameters are either restored in the original storage region or directly delivered to a sound source. The resulting musical sound has an acoustically natural comfortable tone quality. Even if musical sounds are generated simultaneously, no sways in the respective tones of the musical sound are canceled.

Tone parameter control apparatus

Musical tone generating apparatus for electronic musical instrument

Using stored discrete samples of filter coefficients at each of a plurality of discrete operating points, a filter control (e.g., CPU) provides dynamic control of a digital filter through an interpolator in accordance with a variable input indicative of a desired operating point (e.g., cutoff frequency) of the digital filter. In response to a large change in the desired operating point, the control produces a succession of operating point subgoals progressively approaching the changed desired operating point and a corresponding succession of filter coefficient subgoals. Each filter coefficient subgoal is calculated as a function of stored discrete filter coefficient samples near each operating point subgoal. In response to a new parameter set from the filter control, containing a new subgoal of the coefficients, the interpolator starts coefficient interpolating to smoothly move the operating point of the digital filter toward the new subgoal. By starting the interpolating operations after the updating of the parameter set has been completed, synchronization may be established among the interpolating operations on the coefficients.

Digital filter system with changeable cutoff frequency

Using stored discrete samplers of filter coefficients at each of a plurality of discrete operating points, a filter control (e.g., CPU) provides dynamic control of a digital filter through an interpolator in accordance with a variable input indicative of a desired operating point (e.g., cutoff frequency) of the digital filter. In response to a large change in the desired operating point, the control produces a succession of operating point subgoals progressively approaching the changed desired operating point and a corresponding succession of filter coefficient subgoals. Each filter coefficient subgoal is calculated as a function of stored discrete filter coefficient samples near each operating point subgoal. In response to a new parameter set from the filter control, containing a new subgoal of the coefficients, the interpolator starts coefficient interpolating to smoothly move the operating point of the digital filter toward the new subgoal. By starting the interpolating operations after the updating of the parameter set has been completed, synchronization may be established among the interpolating operations on the coefficients.

A tone generation control unit has four waveform read/write channels for selectively the reading or writing data in a waveform memory. A plurality of waveform signals stored in the waveform memory are converted into analog signals to be subjected to timbre and tone volume control through voltage-controlled filters and voltage-controlled amplifiers before being fed to a mixing adder. An output signal of the mixing adder is converted into a digital signal which is stored in the waveform memory again through processing of the tone generation control unit. The stored converted output from the mixing adder is later used again as a new sound source waveform which is operated on to produce tones.

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Iruma, Japan

Kohtaro Hanzawa