Teruo Hiyoshi

Musical tone forming device by fm technology

A musical tone forming device comprises circuit system of digital calculation realizing frequency modulation technology in three different modes. In the first mode a plurality of frequency modulated waveforms are individually calculated in response to key depression and resultant data is added together to provide a musical tone signal, in the second mode, a signal waveform having a frequency corresponding to a depressed key is frequency-modulated with a plurality of signal waveforms, and in the third mode a signal waveform of a frequency corresponding to a depressed key is frequency-modulated in a multiple manner with a plurality of signal waveforms. Throughout these systems, the same component parts are commonly used and tone signals of the respective systems can be produced by a simple switching operation.

Electronic musical instrument with automatic bass chord performance device

An electronic musical instrument comprises an upper keyboard channel, a lower keyboard channel and a pedal keyboard channel. The lower keyboard channel includes a tone gate which is actuated by a chord rhythm pattern pulse generated by an automatic rhythm generator to gate the lower keyboard tones. The pedal keyboard channel includes a root/subordinate tone generator which provide a root tone designated by the depressed pedal key and subordinate tones related to the root tone with predetermined musical intervals, and a tone keyer which is actuated by a bass rhythm pattern pulse generated by the automatic rhythm generator to gate the bass tones.

Electronic musical instrument having a coupler effect

An electronic musical instrument is of a type wherein musical tone waveforms are stored in a memory as their sampled amplitudes and sequentially and repetitively read out to constitute tone waveforms. A key depression brings forth key code in a digital representation. This key code is used for reading out frequency information from a frequency information memory. The frequency informaton is accumulated to make an address signal for reading out the waveform memory. The read out waveform is reproduced as a musical tone through a tone-color and volume control circuit. This tone-color and volume control circuit is controlled keyboard by keyboard. The key code produced upon depression of the key contains a signal representing the kind of the keyboard to which the depressed key belongs. This signal is applied to a conversion circuit and converted to a signal representative of a different kind of keyboard. The output signal of the conversion circuit operates the tone-color and volume control circuit in a manner corresponding to the keyboard designated by the converted signal while the original signal representing the kind of the keyboard of the depressed key is applied directly to the tone-color and volume control circuit to operate it in a manner corresponding to the keybord of the depressed key. The manner of conversion of the signal representing the keyboard can be selected as desired. There is disclosed an example of a coupler effect between the upper and lower keyboard which can be produced by converting a signal for the upper keyboard to a signal for the lower keyboard while directly using the upper keyboard signal. Also disclosed is an example of a coupler effect between the lower keyboard and the pedal keyboard produced by converting a signal for the lower keyboard to a signal for the pedal keyboard while directly using the lower keyboard signal.

Electronic musical instrument having legato effect

An electronic musical instrument is of a type wherein an envelope to be imparted to a musical tone is stored in a memory as its sampled values and sequentially read out to constitute an envelope shape. A key depression causes the read-out of the memory. The instrument is improved to provide a rich sound effect of legato performance by successively and smoothly shifting the tone of the former key to that of the latter key while maintaining a predetermined constant tone volume. This legato effect can be carried out by successively maintaining the sustain level of the musical tone envelope from the tone of the former key shifted to the latter key. The musical tone envelope is read from the envelope memory by an address which is shifted by a clock pulse. After the key has been depressed, the address continues to be shifted by the clock pulse until it has reached a predetermined value, whereupon the supply of the clock pulse is prohibited to cause the envelope memory to produce a sustain level corresponding to the address. Thereafter, this address is held to maintain the sustain level of tones of subsequently depressed keys regardless of whether the initially depressed key ash been released or not, or whether the subsequently depressed keys are being depressed or have been released. An embodiment in which the legato effect is produced with respect to a pedal keyboard is described.

Electronic musical instrument capable of producing "chord pyramid" arpeggio effects

An electronic musical instrument capable of producing a performance effect resembling arpeggio. Tones corresponding to one or more depressed keys are sequentially produced from the lowest tone or the highest tone and an octave range in which tones are produced is shifted toward a higher octave or a lower octave at completion of each cycle of the tone production sequence. This shift of octave is continued to a certain predetermined octave and, after the tone production in the predetermined last octave has been completed, the tone production is repeated from the original octave or the tone production is conducted with the octave range being shifted in a reverse direction. For realizing simulation of arpeggio, plural key information produced by depressing a plurality of keys needs to be selected in a predetermined sequence. To this end, an up-down counter is employed in an example of the present invention. In a mode of arpeggio-like performance in which the tone pitch sequentially rises, for example, counting in the up-down counter is started from 0 for comparing contents of the counter with the key information and, when there is coincidence, the counting is suspended and the lowest tone is produced in response to the key information. After the lapse of a set time, the counting is resumed for repeating the comparison and a next higher tone is produced. The same operation is repeated until the counter overflows, when the octave is shifted to a next octave. The tone production is made at a predetermined time interval (a regular mode) or at a preset time interval from start of depression of the key (a random mode).

Electronic musical instrument with attack repeat effect

An electronic musical instrument capable of producing an attack repeat effect. The attack repeat effect is a musical effect produced by repeated occurrences of attack and decay during a single continued sounding of a musical tone, giving to an audience an impression as if the tone started and stopped repeatedly. According to the invention, a complete envelope shape starting by an attack portion and ending by a decay portion is stored in a memory. When a key on the keyboard is depressed, the stored envelope shape is read from the memory and, upon completion of reading of one cycle of the envelope shape, reading of the envelope shape is resumed from the beginning. A time division multiplexed reading out of the envelope shape is conducted with respect to a plurality of channels. The read out envelope shape is used for controlling the amplitude of the musical tone signal. If the key is released, reading of the envelope shape is no longer repeated for a next and subsequent cycles.

Tone wave generator in electronic musical instrument

In an electronic musical instrument, the keys of a keyboard are divided into a plurality of groups by octaves, and a wave generator is provided with a memory for storing constants corresponding to musical tone frequencies to be generated according to the notes includes in a desired group out of the plurality of group, an accumulator for repeatedly adding the constants read out of the memory, and a bit position shifting circuit for shifting the bit position of the data produced by the accumulator according to the octave range of a note to be produced, thereby to obtain the data varying repeatedly according to the frequency of a note to be produced, and to reduce the storing capacity of the memory when compared to the number of keys.