GB431132A - Improvements in or relating to means for the reproduction of sound, particularly music, from phonograms - Google Patents

Abstract

431,132. Reproducing recorded sound. LEVY, G. C., 40, Avenue de Clichy, Paris. Sept. 28, 1933, Nos. 26781 and 26782. Void [Abridged as open to inspection under Sect. 91 of the Acts, April 3, 1934]. [Class 40 (ii)] Sound is reproduced from a record of any type (disc, cylinder, film, &c.) in the reverse direction to that in which it was initially recorded. Thus, in playing a gramophone record, the direction of rotation of the turntable is reversed, the record being played with the tone-arm shifted so that the pick-up is at the opposite side of the turntable spindle to that on which it is ordinarily used, while the inclination of the needle is unchanged ; or the pick-up is turned so as to reverse the inclination of the needle and the tone-arm moves on the usual side of the turntable spindle. Several devices in gramophones are described, whereby movement of the tonearm or of the pick-up from the normal to the abnormal playing position automatically reverses the direction of drive, or allows such reversal to be made. Fig. 2 shows such a device, in which reversing-gear g is controlled by a lever i operated by a cam h fixed to the tone-arm a. In an electrically-driven machine, switches for reversing the direction of drive may be controlled by the tone-arm. Alternatively, mechanical means may be provided for allowing a reyersing-lever to be actuated only when the tone-arm is in the proper position. Re-recording of an ordinary record reproduced " backwards may be effected, by using an electromagnetic or photo-electric pick-up in conjunction with an amplifier and recording-device, together with means for modifying the tone, pitch, rhythm, &c., if desired. The record thus produced is adapted for use with ordinary reproducing apparatus. The invention is stated to be applicable for use in secret telephone transmission.