GB338593A - Improvements in musical instruments - Google Patents

Abstract

338,593. Jensen, C. A., (Lowrey, F. C.). Aug. 22, 1929. Electrically - vibrated instruments; pipe organs; organ manual coupler and stop actions; flue pipes. - Relates to instruments wherein sounders giving substantially sinewave notes are combined to produce complex tones synthetically, and consists in providing independent controls for regulating the intensity according as to whether a sounder is speaking as a fundamental or as an upper partial. Figs. 1 and 4 show a tuning-fork instrument, forks F, which may also be struck by hammers 38, being vibrated, on closure of key contacts 16, 17, by magnets 22, magnets 41 simultaneously lifting dampers 39. The forks are connected by springs 48 to a soundboard 47. A pulsator P, rotated by a timed device 50, produces pulsations, preferably of the natural period of the fork, in the current from cells 30, the number of which cells in circuit may be varied to vary the voltage and thereby the general intensity. Contacts 18, 19 usually remain closed, for sounding fundamental tones, current passing, on closure of key contacts 16, 17, from the cells 30, through a rocking resistance segment 35 controlling the intensity of the fundamentals, contacts 17, 16, 18, 19, forkmagnet 22, damper relay-magnet 24, and pulsator P. If the same fork is required to sound as the first (or second) harmonic in a complex tone, contacts 52, 53 (or 56, 57) are closed by a stop, a corresponding circuit through another intensity segment 75 (or 78), key contacts 15, 14 (or 13, 12) of the appropriate key, lead 54 (or 58), and contacts 53, 52 (or 57, 56), being completed. Any one key therefore closes pairs of contacts 12 - -17, thus sounding such elements in the complex tone as are represented by closed contacts 18, 19, 52, 53, 56, 57, and each element of the tone being under a separate intensity control 35, 75 or 78. Fig. 8 shows a pipe organ wherein the intensity control of each pure note is obtained by sounding a greater or smaller number of pipes 90 - - 92 in unison. General intensity may be regulated by the swell box 93. For a single note as (say) a fundamental, current passes from battery 30, through the intensity resistance-segment 35, key contacts 17, 16, " fundamental stop " contacts 18, 19 to relay-magnet 122. The shape of the core 114, Fig. 10, and the path of the pivoted armature 110, are arranged so as to produce a movement of a cross-head 111 on the armature which is proportional to the current. The head 111 is inclined, and thus makes contact successively with one or more of the spring fingers 104, 106, 108 guided between the teeth of a comb 109, current then passing from a battery 102, through the bracket 112 and the armature 110, to one or more of the pipe-controlling magnets 98 - - 100. The pipes 90 - - 92, of which there may be any number for each note, may be voiced of unequal loudness. One type of sonorous bodies may be used for the fundamentals, and another for the upper partials.