Abstract: An electronic keyboard musical instrument is operated by a main system computer in a manner dependent on the settings of input elements. A plurality of tone modules are used, each of which comprises a subsystem computer including a subsystem bus, a memory and a microprocessor. Data is exchanged between the main system computer and a subsystem computer through a bus switch which alternately connects the subsystem memory with the main system bus and the subsystem bus. This allows for an effectively "real time" exchange of data between the main system and the subsystem.

Abstract: An electronic musical instrument has input elements such as tone selector keys and control knobs which send input signals representing desired tone parameters to a primary computer. The primary computer, which includes a primary microprocessor and a primary memory, is connected with several voice modules and several effect-producing modules by means of a primary bus. Each voice module has a plurality of tone outputs for generating different tones. The tones for each voice module are produced by a respective subsystem including an auxiliary microprocessor, a clocking device and a digital-analog converter unit which are connected by an auxiliary bus. The auxiliary bus is connected with the primary bus via a bus switch. An auxiliary memory belonging to the subsystem is connected with the bus switch which permits the auxiliary memory to alternately communicate with the primary bus and the auxiliary bus.

Abstract: A function selector has an indicating unit which contains several identical groups of switches. All of the switches are connected with a control input of a microcomputer via a common control conductor. Each group of switches is connected to a different data input of the microcomputer by means of an identification conductor common to all switches of the group. An indicating shift register is associated with every group of switches and each switch of a group, as well as its corresponding light source, are connected to a different stage of the respective indicating shift register. An activating shift register is connected in parallel with each indicating shift register. The stages of the activating shift registers are connected with respective function generating elements. The microcomputer has a series of data outputs each of which is connected both with an indicating shift register and the corresponding activating shift register.

Abstract: An electronic organ has a digital control circuit with a sampling circuit (3) which generates key identification signals (B) in the form of pulse series wherein the pulses denote the actuated keys (2) of the keyboard (1). Such pulses cause a tone selector or evaluating circuit (12) to transmit tone signals to a voicer circuit (15). A shift register (16, 116 or 216) is provided to delay the key identification signals so that the tone signals which the voicer circuit receives do not correspond to those normally expected on actuation of certain keys. The non-delayed key signal can be superimposed upon the delayed signal or signals (V1, V2) in a suitable summing circuit (17) to thus achieve transpositions, interval couplings and other tonal effects.

Abstract: Tone amplitudes of signals which are generated in an electronic organ are converted into digital values and such values are cyclically memorized by a RAM storage at locations which are selected in accordance with a first function. The locations in the storage are then scanned in accordance with one or more second functions which differ from the first function in dependency on time, the thus ascertained or read-out digital values are thereupon converted into analog values, and the analog values are consolidated into processed tone signals. The second functions are or can be derived from the first function.

Abstract: An electronic piano includes a tone generator having a pulse generator and a discrete TOS circuit for each octave. The input of the first TOS circuit is connected with the pulse generator and the input of each next-following TOS circuit is connected with the input of the preceding TOS circuit by a divide-by-two divider circuit. The outputs of each TOS circuit are connected with discrete control circuits each having an analog switch for each output of the respective TOS circuit. First inputs of the analog switches receive envelope control voltage signals on depression of the respective piano keys while second inputs of the analog switches receive tone signals from the corresponding outputs of the respective TOS circuits. The outputs of the analog switches transmit tone signals, which are modulated as a function of the intensity the corresponding envelope control voltage signals, to a loudspeaker by way of either one of two main branches of the respective control circuits.

Abstract: A tone generator system for electronic musical instruments includes a voltage-regulated, high-frequency oscillator. The output of the oscillator is connected with the inputs of first and second 12-tone divider circuits having outputs for transmission of full octaves of tone signals. The connection between the output of the oscillator and the input of one of the divider circuits contains circuitry which intercepts each n.sup.th signal of the series of signals transmitted by the oscillator so that the one divider circuit is out of tune with the other divider circuit. The number n can be varied by a battery of switches and can be as low as 2 or higher than 128. An auxiliary signal dividing circuit can be connected between the output of the oscillator and the input of the other divider circuit.

Abstract: An electronic musical instrument wherein depression of a key entails the discharge of a primary capacitor which is connected to the inverting input of an operational amplifier whose output is connected with a second capacitor serving to supply envelope control voltage signals to an analog switch which connects a tone signal generator with a tone processing unit. The extent to which the primary capacitor discharges depends on the speed of movement of the key from non-depressed to depressed position, and the intensity of residual voltage of the partially discharged primary capacitor determines the intensity of the envelope control voltage signal. The speed at which the second capacitor discharges can be regulated to produce sustain or banjo effects. The second capacitor is in series with a resistor in a feedback conduit connecting the output and the input of the operational amplifier.

Abstract: An electronic organ, piano or accordion has a transposing apparatus wherein a voltage-regulated high-frequency oscillator transmits high frequency signals to the input of a 12-tone divider circuit whose outputs transmit tone frequency signals to the tone generator of the musical instrument. The oscillator receives regulating signals from a switching unit, such as a multiplexer or a battery of integrated circuits, and the intensity of such signals is a function of addressing signals which are transmitted to the switching unit by an addressing unit having a keyboard with keys which are actuatable by the player to initiate the generation of different addressing signals as a result of closing of electric switches which are associated with the keys. The distribution of keys in the keyboard is the same as the distribution of playing keys in the keyboard of a piano, organ or a like musical instrument.

Abstract: A register arrangement for electronic organs wherein the programs which are stored in data storages of distributor circuits on one insertable card can be transferred into the storages of distributor circuits on another insertable card. The one card can be programmed by hand by way of register switches. The storages of distributor circuits on the other card retain the programs upon detachment of the other card so that the latter can be transferred into the register arrangement of another organ.

Abstract: A register arrangement is provided for an electronic musical instrument (such as an electronic organ) whereby the various functional units of the instrument are actuated by electronic selector switches each one of which in turn has a control conductor to which control voltage can be applied by a register assembly either individually or as part of a preselected grouping of functional units.

Abstract: Apparatus for producing vibrato has several analog shift registers with at least 2.sup.9 stages whose inputs receive tone signals from an electronic musical device such as an organ or guitar and are connected to each other. The outputs of the shift registers are connected to a common amplifier. Each shift register receives tone signal transporting pulses from a discrete voltage-controlled high-frequency oscillator, and the inputs of the high-frequency oscillators receive control signals from discrete voltage-controlled low-frequency oscillators whose outputs transmit variable-frequency signals. The output signals of the low-frequency oscillators have different frequencies and are out of phase with respect to each other.

Abstract: An improved gate circuit to suppress bounce is provided for an electronic musical instrument such as an electronic organ. The circuit includes a gate having a first input from a constant supply voltage through a key actuated switch, a second input comprising a sound signal and an output connected to one input of combining or summing circuit hereafter called an integrator. A second input to the integrator comprises a constant, compensating voltage comprising a portion of the supply voltage. The output of the integrator is connected to further processing stages of the instrument.

Abstract: The invention relates to an apparatus for producing a vibrato effect in acoustic signals, particularly for electronic organs, in which the output signals are obtained by successively scanning a plurality of points of a delay line fed by the acoustic signals.