GB912720A - Artificial reverberation control apparatus - Google Patents

Abstract

912,720. Electrical musical instruments. HAMMOND ORGAN CO. June 3, 1960 [June 4, 1959; July 21, 1959], No. 19696/60. Class 88 (2). [Also in Group XXXIX] Audio-frequency electrical signals from an electrical musical instrument are applied to two channels, one of which includes a reverberation device. In one arrangement, Fig. 2, signals from an electric organ 10 are applied through a compensating network 16 to a capacitor-type volume control 18, 20, 22, the electrode 22 of which is connected to an amplifier 28 and loud-speaker 30. A part of the output of amplifier 28 is applied successively to a variable attenuator 34, a reverberation device 42, an amplifier 46 and a loud-speaker 48. The variable attenuator 34 has a variable contactor 40 mechanically coupled to electrode 22 of the capacitor-type volume control and both are simultaneously operable by a control device, e.g. the expression pedal of the electric organ. If the control device is operated to increase the amplitude of signals applied to amplifier 28 the contactor 40 makes contact successively with junctions between resistors R36 in such manner that the amplitude of the signals applied to the loud-speaker 48 increases by a less amount than the amplitude of the signals applied to the loud-speaker 30. In a second arrangement, Fig. 3, audio-frequency electrical signals from an electrical musical instrument 100 are applied to a loud-speaker 160 and, through a filament lamp 180, successively to a reverberation device 300, an amplifier 240 and a loud-speaker 260. The resistance of the filament of lamp 180 increases as the amplitude of the signals applied to it increases such that, as the amplitude of the signals at loud-speaker 160 increases, the amplitude of the signals at loud-speaker 260 also increases but by a less amount.