Mitsumi Kato

Sound effect imparting device for an electronic musical instrument

A sound effect imparting device for an electronic musical instrument is capable of imparting a plurality of desired sound effect such as vibrato and reverberation effects to a digital musical tone generated from the electronic musical instrument. The device comprises a digital arithmetic operation unit constructed with a combination of adders, multipliers, delay circuits, etc., a control unit, a parameter memory and a read-out unit. By control data and parameter data which are respectively read out from the control unit and the parameter memory by means of the read-out unit, switching of the operation mode of the digital arithmetic operation unit is controlled in a time-sharing manner, whereby a plurality of sound effects are imparted to a musical tone through digital arithmetic operations.

Modulation effect device for use in electronic musical instrument

A modulation effect device for use in an electronic musical instrument which utilizes, as a digital modulation circuit, a digital memory device for storing digitized musical tone signals. The digital memory device is accessed by modulation coefficient generating means which supplies a modulated address information to the digital memory device to read out from the memory device a musical tone signal modulated in accordance with the modulated address.

Electronic musical instruments provided with reverberation tone generating apparatus

In an electronic musical instrument, a reverberation tone most suitable for a selected tone color is applied to a musical tone with the selected tone color. In a modification, the electronic musical instrument is provided with a plurality of keyboards and to musical tones to be produced corresponding to the keyboards reverberation tones are applied independently. In another modification, one of the reverberation tones has a reverberation characteristic different from the other reverberation tone.

Electronic musical instrument by nonlinearly addressing waveform memory

In an electronic musical instrument wherein a frequency information related to the tone pitch of a depressed key is repeatedly accumulated and the progressing accumulated value is used to designate the addresses of a waveform memory device storing the waveform of a desired musical tone, the frequency information is varied with time instantaneously so as to vary the speed of addressing the waveform memory and thereby to vary the waveform read out from the waveform memory device, thus changing the color of the produced musical tone.

Electronic musical instrument forming tone waveforms

A frequency number corresponding to the frequency of a tone intended to be sounded is accumulated in an accumulator at every calculation timing of a constant interval to produce values progressing at a rate corresponding to the tone frequency. At this rate, waveform amplitude value samples are sequentially produced one after another in a tone producing section using the output of the accumulator as phase angle data. A reset circuit is provided in connection with the accumulator and this circuit functions to compulsorily reset the progressing values in the accumulator to its initial value in response to a carry out signal generated at the calculation timing when the phase angle data has reached its predetermined modulo value. Thus the period of progress of the phase angle data is harmonized with the calculation timing, i.e., the sampling timing. As a result, the frequency of a tone waveform signal, whatever it may be, can be harmonized with the sampling frequency while the interval of the respective sampling timing is maintained constant.