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: A keyboard unit for an electronic organ wherein the bed of the housing supports two adjustably mounted bearing members which are adjacent the inner sides of the respective side walls of the housing and have round holes for posts provided in the end portions of C-bars forming part of discrete pivotable carriers for tablets, switches, stops, drawbars, keys or analogous components. The components are mounted on plate-like supports which are secured to the respective C-bars by screws extending through the slots of the respective C-bars and mating nuts non-rotatably but slidably installed in the respective C-bars. The two lowermost supports carry piano type manual keyboards, and the additional support or supports carry tablets, switches, drawbars or the like.

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.