Abstract A harmonic synthesis organ in which a complex wave tone generator generates signals corresponding to the frequencies of the fundamentals and hormonic partials. The complex tones are gated and are collected on a plurality of headers, each header corresponding to a particular harmonic partial. The headers are subdivided into groups of approximately one octave of contiguous tones and the groups are individually attenuated by a multiple attenuator controlled by a control element which may be a manually operated draw bar. The outputs of the attenuators are connected to sharp cut off filters which remove all of the natural harmonics from the complex waves, and pass to the amplifier sine waves corresponding to the various partials. A preferred multiple attenuator system employs a plurality of photo resistors associated with a lamp, the intensity of which is controlled by a related draw bar. A lamp control circuit is provided to improve the responsiveness of the lamp to changes in draw bar position. Additional stop control means are provided for controlling the attenuators from either draw bars or from an alternate control system. In the embodiments shown, only a single key contact is associated with each playing key of the organ.
An organ of the harmonic synthesis type comprising: a series of tone generators for producing complex wave tone signals corresponding to the notes of a musical scale over a range of several octaves; a keyboard; a gating system comprised of a plurality of sets of gates, each set including a separate gate connected to each key and to a specific tone generator; a first tone collecting header, divided into group headers of approximately twelve notes, for collecting from one of said sets of gates each wave output signals corresponding in fundamental frequency to the fundamental frequencies of any notes played on said keyboard; a plurality of additional tone collecting headers, each divided into group headers of approximately twelve notes, and each connected to collect from a different set of gates complex wave signals corresponding in fundamental frequency to the frequency of a selected harmonic partial of any notes played on said keyboard; a plurality of multiple section attenuators, one for each tone collecting header, and each having a variable impedance element for each of said group headers; a plurality of sharp cut off filters are adapted to pass a band of frequencies approximately one octave wide and to attenuate sharply all frequencies above its pass band; and means connecting each said variable impedance elements between one group header and one of said sharp cut off filters.
Claim 2
Dependent Claim
226 words
An organ of the harmonic synthesis type comprising: a series of tone generators for producing complex wave tone signals corresponding to the notes of a musical scale over a range of several octaves; a keyboard; a gating system comprised of a plurality of sets of gates, each set including a separate gate connected to each key and to a specific tone generator; a first tone collecting header, divided into group headers of approximately twelve notes, for collecting from one of said sets of gates each wave output signals corresponding in fundamental frequency to the fundamental frequencies of any notes played on said keyboard; a plurality of additional tone collecting headers, each divided into group headers of approximately twelve notes, and each connected to collect from a different set of gates complex wave signals corresponding in fundamental frequency to the frequency of a selected harmonic partial of any notes played on said keyboard; a plurality of multiple section attenuators, one for each tone collecting header, and each having a variable impedance element for each of said group headers; a plurality of sharp cut off filters are adapted to pass a band of frequencies approximately one octave wide and to attenuate sharply all frequencies above its pass band; and means connecting each said variable impedance elements between one group header and one of said sharp cut off filters.
Claim 3
Dependent Claim
42 words
The combination set forth in claim 1 in which each multiple section attenuator includes a plurality of respectively related input and output terminals; and unitary control means for simultaneously varying the transmission of signals between the said respective input and output terminals.
Claim 4
Dependent Claim
33 words
The combination set forth in claim 2 in which the unitary control means includes a terminal the potential of which determines the amplitude of signals transmitted between the respective input and output terminals.