An electronic organ with automatic chord and bass systems

Claim 2

An electronic musical instrument comprising: a tone generator for producing a plurality of signals of different audio frequencies; a first tone coloring filter for converting audio signals to musical tone signals; an upper keyboard channel including a plurality of key controlled switches for selectivity connecting signals from said tone generator to said tone coloring filter; a second tone coloring filter; a first gate circuit having its output connected to said second tone coloring filter; a lower keyboard channel including a plurality of switches for selectively connecting signals from said tone generator to said first gate circuit; a pedal keyboard channel including chord detecting means connected to said lower keyboard channel for detecting the kind of chord being played by said lower keyboard; bass tone selector means connected to said tone generator and said chord detecting means for selecting a pair of bass tone signals corresponding to the root and fifth of the chord being played by said lower keyboard; a third tone coloring filter for converting bass tone signals to bass tone musical signals; a second gate circuit connected between said bass selector means and said third tone coloring filter; amplifier means connected to the output of each of said tone color filters; loud speaker means connected to the output of said amplifier means; and means for generating rhythm pattern pulses and connected to control said first and second gate circuits, said bass tone selector means and second gate circuit including a pair of transistors and means for supplying said transistors with bass tone signals corresponding to the root and fifth of a chord to be played by said lower keyboard, the emitters of said transistors being jointly connected to the output of said chord detector; a pair of diodes one connected between the emitter of each transistor and said chord detector in a direction opposed to the base-emitter diode; a pair of resistors, one connected between the emitter of each transistor and ground; and a further pair of diodes, one connected between the emitter of each transistor and said rhythm pattern pulse generator in a direction opposite to the base-emitter diode.

Claim 3

An electronic musical instrument comprising: a tone generator for Producing a plurality of signals of different audio frequencies; a first tone coloring filter for converting audio signals to musical tone signals; control switches for selectively connecting signals from said tone generator to said tone coloring filter; a second tone coloring filter; a first gate circuit having its output connected to said second tone coloring filter; a lower keyboard channel including a plurality of switches for selectively connecting signals from said tone generator to said first gate circuit; a third tone coloring filter for converting bass tone signals to bass tone musical signals; a second gate circuit having its output connected to the input of said third tone coloring filter; a pedal keyboard channel including means connected to said lower keyboard channel for selectively connecting bass tone signals corresponding to the lowest and highest notes included in a chord played by said lower keyboard channel to the input of said second gate; amplifier means connected to the output of each of said tone color filters; loud speaker means connected to the output of said amplifier means; and means for generating rhythm pattern pulses and connected to control said first and second said gate circuits, said means to selectively connect base tone signals corresponding to the lowest and highest notes included in the chords played by the lower keyboard to the input of said second gate comprising: first and second groups of switches controlled by the keys of said lower keyboard and each switch having a movable contact, a normally closed fixed contact and a normally open fixed contact, said movable contact of each switch of said first group being connected to said normally closed fixed contact of an adjacent switch associated with the adjacent lower note section, said normally open fixed contact of said each switch being connected to said tone generator, said movable contact of each switch of said second group being connected to the normally closed fixed contact of an adjacent switch associated with the adjacent higher note section, said normally open fixed contact of said each switch of said second group being connected to said tone generator to which there is connected said normally open fixed contact of that switch of said first group which is operated by the same key of said lower keyboard, whereby the lowest bass tone signal to be selected is derived from said movable contact of the switch disposed in the lowest tone section in said first switch group and the highest bass tone signal to be selected is derived from the movable contact of the switch disposed in the highest tone section of said second switch group.

Claim 4

An electronic musical instrument comprising: a tone generator for Producing a plurality of signals of different audio frequencies; a first tone coloring filter for converting audio signals to musical tone signals; control switches for selectively connecting signals from said tone generator to said tone coloring filter; a second tone coloring filter; a first gate circuit having its output connected to said second tone coloring filter; a lower keyboard channel including a plurality of switches for selectively connecting signals from said tone generator to said first gate circuit; a third tone coloring filter for converting bass tone signals to bass tone musical signals; a second gate circuit having its output connected to the input of said third tone coloring filter; a pedal keyboard channel including means connected to said lower keyboard channel for selectively connecting bass tone signals corresponding to the lowest and highest notes included in a chord played by said lower keyboard channel to the input of said second gate; amplifier means connected to the output of each of said tone color filters; loud speaker means connected to the output of said amplifier means; and means for generating rhythm pattern pulses and connected to control said first and second said gate circuits, said means to selectively connect base tone signals corresponding to the lowest and highest notes included in the chords played by the lower keyboard to the input of said second gate comprising: first and second groups of switches controlled by the keys of said lower keyboard and each switch having a movable contact, a normally closed fixed contact and a normally open fixed contact, said movable contact of each switch of said first group being connected to said normally closed fixed contact of an adjacent switch associated with the adjacent lower note section, said normally open fixed contact of said each switch being connected to said tone generator, said movable contact of each switch of said second group being connected to the normally closed fixed contact of an adjacent switch associated with the adjacent higher note section, said normally open fixed contact of said each switch of said second group being connected to said tone generator to which there is connected said normally open fixed contact of that switch of said first group which is operated by the same key of said lower keyboard, whereby the lowest bass tone signal to be selected is derived from said movable contact of the switch disposed in the lowest tone section in said first switch group and the highest bass tone signal to be selected is derived from the movable contact of the switch disposed in the highest tone section of said second switch group.