Electronic musical instrument with means for automatically generating chords and harmony2010-02-05 00:00:00instrument.
These and other objects and advantages of the present invention will become manifest by an inspection of the accompanying drawings and the following description.
In one embodiment of the present invention there is provided an integrated circuit formed of a single chip of semiconducting material, incorporating multiplexing means for producing a train of pulses in response to operation of a plurality ofswitches, some of which are operated in response to depression of keys of the keyboard of a musical instrument, a plurality of read only memories responsive to addresses derived from said train of pulses and each being operative to produce a uniquesignal having a pulse repetition rate corresponding to an individual element of a chord associated with a depressed key, a plurality of frequency dividers connected to receive the signals produced by said read only memories, a logic network forcontrolling the operation of said divider chains to produce output signals having a controlled pitch, and control means for controlling the timing at which the output signals are produced.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made to the accompanying drawings, in which:
FIG. 1 is a functional block diagram of an electronic musical instrument incorporating an illustrative embodiment of the present invention;
FIG. 2 is a functional block diagram in more detail of a portion of the apparatus illustrated in FIG. 1;
FIG. 3 is a schematic diagram of a portion of a keyboard and a plurality of function control switches associated with the logic unit of FIG. 1;
FIG. 4, comprising FIGS. 4a through 4f, constitutes a schematic block diagram in more complete detail of a portion of the apparatus of FIG. 1;
FIG. 5 is an illustration of how FIGS. 4a-4f are interconnected;
FIG. 6-10 are functional block diagrams of the divider control logic unit 272 and the divider units for the various chord components; and
FIG. 11 is a functional block diagram of one of the tone signal generators.
DESCRIPTION OF THE PREFERRED EMBODIMENT
General
Referring first to FIG. 1, the musical instrument of the present invention incorporates a keyboard 10 which is connected by a number of lines 12 with a logic unit 14. A power supply 16 provided with a line chord 17 is provided to supplyelectrical power to the logic unit 14, and it processes information received from the keyboard and from a plurality of auxiliary switches (not shown ) and produces a plurality of outputs on a number of output lines 18. The output lines 18 are connectedto inputs of a plurality of keyers 20, which also receive power from the power supply 16, and the outputs of the keyers 20 are passed through one or more voicing units within a voicing section 22; the output of the voicing section 22 is amplified by anamplifier 24 and is supplied to a loudspeaker 26. The amplifier 24 is also supplied with power from the power supply 16.
Not shown in FIG. 1 is a plurality of auxiliary function control switches, such as the normal switches or tablets usually associated with electronic organ keyboards. A variety of such switches are provided and function in the normal way
tocontrol the amplifier 24 and the voicing section 22, as well as the keyers 20. They also control the logic unit 14, in ways which are described hereinafter. Of the units in FIG. 1, only the logic unit 14 is not conventional. All of the other unitscorrespond to known apparatus available in the art, and any of a number of different constructions may be employed.
In FIG. 2, a general block diagram of the logic unit 14 and its associated structure is illustrated.
A clock signal generator 28 is provided for producing a series of clock pulses on a line 30, for regulating operation of the logic unit. The line 30 is connected to the input of a multiplexer 32, which is connected to a number of differentfunctional units. In addition to the keyboard 10, the multiplexer 32 is connected to a plurality of function control switches 34, a plurality of note latches 36, a plurality of function latches 38, and a serial data unit 40. The function of themultiplexer 32 is to examine the state of the keys of the keyboard 10 and the various switches of the functional switches 34, and to produce signals for controlling the latches 36 and 38 so that the latches are set in accordance with the depressed keysof the keyboard and the operated function control switches.
The serial data unit 40 is responsive to the multiplexer 32 an also to the function latches 38 for producing on an output line 42 a pulse train including a pulse for at least one of the operated keys of the keyboard 10, as well as some additionalpulses which are inserted under control of the serial data unit 40. The pulses on the line 42 are passed to other apparatus (not shown) and employed to produce musical sounds corresponding, in frequency, to the time position of each of the pulses in thetrain.
The note latches 36 provide an output on the line 43 which is applied to a plurality of generators 44-48. The generator 44 produces signals corresponding in frequency to that of the root of a given chord, a generator 45 produces signalscorresponding to the musical third of the chord, and the generators 46-48 produce signals having frequencies corresponding to the musical fifth, sixth and seventh of the chord.
The generators 44-48 each produce an output which is connected to an individual divider unit of a set of such units 50-54. The outputs of the divider units 50-54 are all connected to inputs of an operation control unit 56, and the operationcontrol unit 56 in turn controls operation of the divider units 50-54 by means of signals on lines illustrated in FIG. 2 by lines 58-62.
The operation control unit 56 also receives signals from the rhythm unit 66 over a line 68. A number of outputs are produced by the control unit 56, as follows. A line 71 produces a chord output corresponding to a chord produced by operation ofthe control unit 56. A plurality of lines illustrated by the line 72 in FIG. 2 produces a number of signals in time suc...
