U.S. patent number 3,697,661 [Application Number 05/186,360] was granted by the patent office on 1972-10-10 for multiplexed pitch generator system for use in a keyboard musical instrument.
This patent grant is currently assigned to North American Rockwell Corporation. Invention is credited to Ralph Deutsch.
United States Patent |
3,697,661 |
Deutsch |
October 10, 1972 |
MULTIPLEXED PITCH GENERATOR SYSTEM FOR USE IN A KEYBOARD MUSICAL
INSTRUMENT
Abstract
The present invention is a multiplexed pitch generator system
for use in a keyboard musical instrument to activate the voice
controls of the instrument in accordance with key depressions. In
the preferred embodiment of the invention there is provided a means
for stepping pulses into a plurality of time slots in a cyclic
manner. A plurality of keys are provided with each time slot
corresponding to one particular key, and each key corresponding to
a particular note. Pitch means are provided for receiving the time
division multiplex signal with the gated pulses and for shifting
the time slot position of selected pulses to a desired time slot
location so as to simulate another note. Comparing means are used
to compare the time slot position of the pulses from the pitch
means with the time division multiplex signal to determine the
final time slot position of a pulse. Latching means corresponding
in number to the number of time slot positions are connected to the
comparing means with each individual latching means being activated
by a pulse occurring only in its associated time slot. The latching
means, in turn, activates the voice controls of the keyboard
musical instrument to sound the note or pitch associated with the
pulses' final time slot location. In a second embodiment of the
invention which is used on a multiple keyboard instrument, each
keyboard has one multiplexed pitch generator system associated
therewith and, in addition, the output signal from the pitch
generating means of one or more keyboards are connectable to the
outputs from the other multiplexed pitch generators such that the
musician can play a key on one keyboard and have it sound as if
played from another keyboard.
Inventors: |
Deutsch; Ralph (Sherman Oaks,
CA) |
Assignee: |
North American Rockwell
Corporation (N/A)
|
Family
ID: |
22684633 |
Appl.
No.: |
05/186,360 |
Filed: |
October 4, 1971 |
Current U.S.
Class: |
84/655; 84/669;
984/332; 84/660; 984/338 |
Current CPC
Class: |
G10H
1/20 (20130101); G10H 1/182 (20130101) |
Current International
Class: |
G10H
1/20 (20060101); G10H 1/18 (20060101); G10h
001/00 () |
Field of
Search: |
;84/1.01,1.03,1.24,1.26 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Myers; Lewis
Assistant Examiner: Weldon; U.
Claims
I claim:
1. In an electronic musical instrument having keys selectively
activable to cause the production of sounds corresponding to
respective notes on the musical scale, the combination
comprising:
means for generating a first train of pulses wherein each pulse
represents a particular time slot;
means for generating a second train of pulses wherein each pulse
represents a cycle corresponding to a plurality of time slots;
first shift register means having a plurality of stages
corresponding in number to the number of time slots in one cycle of
said second pulse train for receiving said first and second train
of pulses wherein said shift register steps a pulse from said
second pulse train sequentially through each of said stages in time
sequence with the pulses from said first pulse train;
a keyboard comprised of a plurality of keys corresponding in number
to said plurality of shift register stages, with each of said keys
connected to corresponding stages of said shift register so that
activation of a key passes the stepped pulse stored in the
corresponding stage of said shift register as an output signal;
tone generating means for producing a tone for each of said
plurality of keys;
second shift register means having a plurality of stages
corresponding in number to the number of time slots in one cycle of
said second pulse train for receiving said first and second train
of pulses wherein said shift register steps a pulse from said
second pulse train sequentially through each of said stages of said
shift register in time sequence with the pulses from said first
pulse train; and
comparing means for comparing the time slot position of the stepped
pulse at the output of said keyboard with the pulse slot position
in said second shift register so as to activate a tone in said tone
generating means when there is a coincidence of pulses in the
compared signals.
2. The musical instrument according to claim 1 and further
comprising:
pitch keyboard means interposed between the output of said keyboard
and the input to said comparing means for selectively shifting the
time slot position of the stepped pulse in the output signal so as
to activate another tone in said tone generating means other than
the one corresponding to the activated key.
3. The musical instrument according to claim 1 and further
comprising:
a third shift register means connected to receive said first and
second train of pulses;
a second keyboard connected to said third shift register means;
a second tone generating means for producing tones different for
each of the associated plurality of said second keyboard keys;
fourth shift register means having a plurality of stages
corresponding in number to the number of time slots in one cycle of
said second pulse train, for receiving said first and second train
of pulses wherein said fourth shift register steps a pulse from
said second pulse train sequentially through each of said stages of
said shift register in time sequence with the pulses form said
first pulse train;
a second comparing means for comparing the time slot position of
the stepped pulses from the second keyboard with the pulse slot
position in said fourth shift register so as to activate a tone in
said second tone generating means when there is a coincidence of
pulses in the compared signals; and
coupling means for coupling the output signal of said first
keyboard to the input of said second comparing means when said
coupling means is activated, whereby a key activated on said first
keyboard causes a tone to be generated by said second tone
generating means.
4. The musical instrument according to claim 3 and further
comprising:
a fifth shift register means connected to receive said first and
second train of pulses;
a third keyboard means connected to said fifth shift register
means;
a third tone generating means for producing tones different for
each of the associated plurality of said third keyboard keys;
a sixth shift register having a plurality of stages corresponding
in number to the number of time slots in one cycle of said second
pulse train, for receiving said first and second train of pulses
wherein said sixth shift register steps a pulse from said second
pulse train sequentially through each of said stages of said sixth
shift register in time sequence with the pulses from said first
pulse train;
a third comparing means for comparing the time slot position of the
stepped pulses from the third keyboard with the pulse slot position
in said sixth shift register so as to activate a tone in said third
generating means when there is a coincidence of pulses in the
compared signals; and
second coupling means for coupling the output signal of said second
keyboard to the input of said third comparing means when said
second coupling means is activated, whereby a key activated on said
second keyboard causes a tone to be generated by said third tone
generating means.
5. The musical instrument according to claim 4 and further
comprising:
third coupling means for coupling the output signal of said first
keyboard to the input of said third comparing means when said third
coupling means is activated, whereby a key activated on said first
keyboard causes a tone to be generated by said third tone
generating means.
6. The musical instrument according to claim 3 and further
comprising:
a second pitch keyboard means interposed between the output of said
second keyboard and the input to said second comparing means for
selectively shifting the time slot position of the stepped pulse
from the second keyboard output signal so as to activate another
tone in the second tone generating means other than the one
corresponding to the activated key of the second keyboard.
7. The musical instrument according to claim 6 and further
comprising a summing means for receiving as an input the signal
from said second pitch keyboard means; and
a key connecting the output signal of said coupling means to
another input of said summing means when said key is activated.
8. The musical instrument according to claim 7 wherein each of said
pitch keyboard means is comprised of an intramanual shift register
having a plurality of stages for receiving the output signal from
said keyboard means and having an intramanual keyboard comprised of
a number of keys which keys are connected to desired stages of said
shift register, whereby activation of said keys passes to said
comparing means the pulses stored in the corresponding stage of
said intramanual shift register.
9. The musical instrument according to claim 8 and further
comprising:
a first and second intermanual coupler means connected to receive
the output of said first and second pitch keyboard means,
respectively, for altering the time slot position of the stepped
pulse signals from said first and second pitch keyboard means and
for feeding said altered signal to said first and said second
comparing means, respectively.
10. The musical instrument according to claim 9 wherein said
intermanual couplers are comprised of an intermanual shift register
having a plurality of stages; and
an intermanual keyboard comprised of a number of keys which keys
are connected to desired stages of said shift register whereby
activation of said keys passes to said comparing means the pulse
signal stored in the corresponding stage of said intermanual shift
register.
11. The musical instrument according to claim 4 and further
comprising:
a third pitch keyboard means interposed between the output of said
third keyboard and the input to said third comparing means for
selectively shifting the time slot position of the stepped pulse
from the third keyboard output signal so as to activate another
tone in said third tone generating means other than the one
corresponding to the activated key of the third keyboard.
12. The musical instrument according to claim 11 wherein each of
said pitch keyboard means is comprised of an intramanual shift
register having an intramanual keyboard comprised of a number of
keys which keys are connected to desired stages of said shift
register, whereby activation of said keys passes to said second
comparing means the pulses stored in the corresponding stage of
said intramanual shift register.
13. The musical instrument according to claim 11 and further
comprising:
a first, second and third intermanual coupler means connected to
receive the output of said first, second and third pitch keyboard
means respectively for altering the time slot position of the
stepped pulse signals from said first, second and third pitch
keyboard means and for feeding said altered signals to said first,
second and third comparing means, respectively.
14. The musical instrument according to claim 8 and further
comprising:
an octave time gate connected to receive the pulses stored in one
stage of said intramanual shift register and the pulses from said
first pulse train, said time gate having a plurality of outputs
each indicative of a separate octave whereby the received pulses
are gated sequentially to each of the outputs;
a plurality of mixture shift register means, one each connected to
receive the output of said octave time gate, each of said mixture
shift registers operating to shift the time slot position of said
stepped pulse by a selected amount; and
summing means for summing the outputs of said plurality of mixture
shift register means and for feeding said summed signal to said
comparing means.
15. The musical instrument according to claim 8 and further
comprising:
an octave time gate for receiving said first and said second train
of pulses and for providing non-overlapping timing pulses
corresponding to different octaves of the musical scale;
an octave mixer shift register having a plurality of stages for
receiving as an input the pulses stored in one stage of said
intramanual shift register;
a plurality of gates corresponding in number to the octaves of said
musical instrument for receiving the signals from selected ones of
said octave mixer shift register stages and wherein each gate
receives a timing pulse from said octave time gate whereupon
coincidence of said received signals causes said gate to pass the
signals present on its inputs; and
summing means for summing the outputs of said gates and for feeding
said summed signal to said comparing means.
16. In an electronic musical instrument having a keyboard with a
number of selectively actuable keys for causing the production of
sounds corresponding to respective notes of the musical scale, the
combination comprising:
means for sequentially positioning a pulse into individual time
slots of a cyclically repeating signal for passing a pulse
contained in a corresponding time slot of said repeating signal
when said key is activated;
keyboard means having a plurality of keys corresponding to each
time slot of said cyclically repeating signal for passing a pulse
contained in a corresponding time slot of said repeating signal
when said key is activated;
comparing means for receiving said passed pulse and said cyclically
repeating signal and for providing a latching signal when the time
slot position of said passed pulse corresponds to the pulse
position of said cyclically repeating signal;
tone generating means responsive to said latching signal for
sounding a note corresponding to the key depressed; and a pitch
keyboard means for receiving the passed signal of said keyboard
means and for selectively shifting the time slot position of the
passed pulse and for feeding the shifted pulse signal to said
comparing means so as to cause another note to sound other than the
one corresponding to the activated key.
17. The musical instrument according to claim 16 wherein there is
provided a plurality of keyboard means and a corresponding
plurality of comparing means with the output of each keyboard means
being coupled to the other keyboard means such that a key activated
on one keyboard will sound a selective note in said tone generating
means as if the note were played on said other keyboard means.
18. The musical instrument according to claim 17 and further
comprising:
intramanual coupler means interposed between the output of said
pitch keyboard means and the input of said comparing means for
selectively providing a shift to the pulse time slot position of
the signal from said pitch keyboard means.
19. The musical instrument according to claim 18 wherein said
intramanual coupler means is comprised of:
an intermanual shift register having a plurality of stages; and
an intermanual keyboard comprised of two keys connected to each
used stage of said intermanual shift register with one key from
each stage connectable to the comparing means associated with said
intermanual keyboard and with the other key from each stage of said
intermanual shift register connectable to the input of another
comparing means.
20. The musical instrument according to claim 17 and further
comprising:
an octave time gate connected to receive the pulses stored in one
stage of said intermanual shift register and the pulses from said
first pulse train, said time gate having a plurality of outputs
each indicative of a separate octave whereby the received pulses
are gated sequentially to each of the outputs;
a plurality of mixture shift register means, one each connected to
receive the output of said octave time gate, each of said mixture
shift registers operating to shift the time slot position of said
stepped pulse by a selected amount; and
summing means for summing the outputs of said plurality of mixture
shift register means and for feeding said summed signal to said
comparing means.
21. The musical instrument according to claim 17 and further
comprising:
an octave time gate for receiving said first and said second train
of pulses and for providing non-overlapping timing pulses
corresponding to different octaves of the musical scale;
an octave mixer shift register having a plurality of stages for
receiving as an input the pulses stored in one stage of said
intramanual shift register;
a plurality of gates corresponding in number to the octaves of said
musical instrument for receiving the signals from selected ones of
said octave mixer shift register stages and wherein each gate
receives a timing pulse from said octave time gate whereupon
coincidence of said received signals causes said gate to pass the
signals present on its inputs; and
summing means for summing the outputs of said gates and for feeding
said summed signal to said comparing means.
Description
BACKGROUND OF THE DISCLOSURE
The invention is directed to a system for unifying and coupling the
keyboards of a musical instrument, which system eliminates the
large amount of conventional cabling and multicontact keys. The
invention is further directed toward an economical and reliable
solution to a construction problem in the design of electronic and
pipe organs. With prior solutions, the general directives were to
obtain increased capability. Except for very early instruments, the
subsystems that have been in use are substantially identical in
operation and require no special training on the part of the
organist. More specifically, the present invention is concerned
with pitch generation and the couplers which accomplish this
generation. In the musical world, a set of couplers is a subsystem
designed to obtain multiple usage from a rank of pipes. One of the
simpler examples of a coupler is that of the unison pitch
intermanual coupler. This is the organist's term denoting that the
pitch of each note corresponds to the nominal pitch of the keys on
the keyboard. For example, with the organist playing on the Great
manual, to obtain the particular sound desired, the organist wishes
to draw upon the pipes that are assigned to the Swell manual, which
is done by causing the Swell pipes to sound from the Great manual
by activating the Swell-to-Great intermanual coupler. With this
coupler actuated, the action is equivalent to keying each Swell key
as each of the corresponding Great keys are depressed. Older organs
accomplished this type of coupling by using a subsystem of levers
so that the Swell keys were mechanically depressed at the same time
that a Great key was depressed. The present invention accomplishes
this electronically.
Another frequent use of couplers is to get multiple use of a rank
of pipes while playing on the same keyboard to which the rank of
pipes is assigned. An example of this type of coupler is the
intramanual coupler.
For an illustration, suppose that the organist is playing on the
Swell manual and actuates the "Swell-to-Swell 4'" coupler. Now each
note he plays will automatically sound at the 8' pitch (unison) and
will also sound at the 4' pitch (an octave higher). It is also
common to have intramanual couplers at other pitches. Thus, a
"Swell-to-Swell 16'" will cause the unison note to be played as
well as the note an octave lower in pitch.
The use of couplers to add new pitches can also be extended to
intermanual couplers. Thus, a "Swell-to-Great 4'" will cause the
Great keys to actuate all the stops drawn on the Swell manual but
will have these coupled stops sound an octave higher than the
unison pitch. Similarly, a "Swell-to-Great 16'" will cause the
Great keys to actuate the Swell stops at an octave below unison
pitch.
Another use of couplers is to "unify" the various voices of an
organ. Unified organs were first extensively used in theatre pipe
organs as a method of getting a lot of mileage from each rank of
pipes. Although the average theatre organ had only about 8 ranks of
pipes, the consoles contained approximately 50 stops. There was a
period of pipe organ construction in this country during which
church organ builders also succumbed to unification; partly from
mistaken ideas on tonal quality and partly because unification
provides a very large number of stops which leads to an impressive
console. Unification is used almost universally and extensively in
the design of electronic organs. Unification is a form of manual
coupler but is restricted to a single voice. For example, suppose
that the organ has a rank of flute tones at the 8' or unison pitch.
To obtain a 4' flute from this same rank, the organ keyboard is
wired so that when the 4' stop is actuated, each key operates a
pipe which is an octave higher than unison pitch. Similarly a 16'
flute is obtained by unifying so that the keyboard operates a pipe
which is an octave lower than the unison pitch that is keyed.
There have been many systems proposed and implemented for
unification. Conventional unification schemes use a system of
multiple contacts associated with each key on the keyboards. In
some cases these multiple contacts have been removed from the
immediate vicinity of the keyboard by employing such contact
multiplying devices as multicontact electrical relays or, for
example, keying diodes.
SUMMARY OF THE INVENTION
In a preferred embodiment of this invention, the system is
comprised of a means for stepping a pulse into a plurality of time
slots in a cyclic manner. A plurality of keying means are provided
with the number of keying means corresponding in number to the
number of slots for gating a pulse into a time slot of a time
division multiplex signal, with each time slot corresponding to one
particular key, and each key corresponding to a particular note,
such that the time slot position of the pulse corresponds to a
particular note. Pitch means are provided for receiving the time
division multiplex signal and for shifting the time slot position
of selected pulses to a desired time slot location so as to
simulate a note other than the one played. Comparing means are used
to correlate the location of the pulse in the time division
multiplex signal to a corresponding organ note.
In another embodiment of the invention, two or more identical
systems are provided, one for each keyboard. The output from one
pitch means is connectable to the output of a second pitch means to
allow the organist to play a key on one keyboard and have it sound
as if played on another keyboard.
From the foregoing, it can be seen that it is an object of the
present invention to provide an improved multiplexed pitch
generator.
It is a further object of the present invention to provide a pitch
generator which is capable of intermanual and intramanual
coupling.
It is another object of the present invention to provide a system
for coupling keyboards of a musical instrument.
It is a further object of the present invention to allow the
playing of a key on a musical instrument and having a note sound
other than the one normally associated with the key.
It is an additional object of the present invention to provide a
system for intercoupling of keyboards.
These and other objects of the present invention will be better
understood when taken in conjunction with the following description
and drawings in which like characters indicate like parts and which
drawings form a part of this application.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates, in electronic block diagram form, one
embodiment of the present invention;
FIG. 2 illustrates, in electronic block diagram form, a second
embodiment of the present invention for use in conjunction with the
embodiment of FIG. 1.
FIG. 3 illustrates, in electronic block diagram form, an
intramanual coupler which may be used with the embodiment of FIG. 1
or FIG. 2.
FIG. 4 illustrates, in electronic block diagram form, couplers
which may be used with the embodiment of FIG. 1.
FIG. 5 illustrates a one octave mixture generator for use with the
system.
FIG. 6 illustrates a multi-octave mixture generator for use with
the system.
FIG. 7 illustrates another embodiment of a multi-octave mixture
generator.
FIGS. 8a to 8f illustrate waveforms used in gating the multi-octave
mixture generator of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The circuits illustrated in FIG. 1 comprise the circuits necessary
for one multiplexed keyboard. If two or more keyboards are used,
the circuits of FIG. 1 will be duplicated for each keyboard. The
multiplexed keyboard circuit is comprised of a basic clock
generator 10 which feeds pulses at a fixed repetitious rate to a
pulse frequency divider 11. The output of pulse frequency divider
11 is fed to a pulse locator means 13 which is comprised of shift
register 14 and a corresponding number of keys 15. The output pulse
from pulse frequency divider 11 controls the rate of shifting
between stages of the shift register. These pulses are also fed to
a frequency divider 12. Frequency divider 12 supplies a locator
pulse once each multiplex period to the input shift register 14.
The locator pulse is stepped through each of the shift register
stages at a rate corresponding to the pulse rate of the pulses from
frequency divider 11. The pulse frequency divider 11 operates to
divide the basic clock frequency from clock 10 such that 97 times
slots, corresponding to the 97 notes for a full keyboard (4' and 2'
pitches added), can be scanned in T seconds, with T seconds
corresponding to the multiplex period. Therefore, once every T
seconds frequency divider 12 provides a locator pulse. The
multiplex period, T, for good performance, should be in the range
of 2 to 5 milliseconds. As previously stated, the second frequency
divider 12 is set to establish a pulse for the input to the shift
register 14 once each multiplex period which pulse travels from one
stage of the shift register to another stage until it finally
reaches the last stage at the end of one multiplex period (cycle).
The normal open keys 15, which correspond to notes, connect one
associated shift register stage to the output terminal 16 when
depressed (closed). Therefore, the output signal appearing at
terminal 16 can be viewed in terms of a repeating picture having 97
individual time slots, with the occurrence of a locator pulse in a
particular time slot providing an indication that the key
associated with that particular time slot is being depressed. The
actual pulse location can be determined through coincidence, that
is, the occurrence of a pulse in a particular time slot is compared
against a pulse positioned in a known time slot and when the two
coincide, the particular note associated with that pulse position
is sounded by the keyboard instrument. The coincidence comparing
circuit used with the present invention consists of a shift
register 18 which is identical in construction to shift register
14. The shift register 18 steps the locator pulses from pulse
frequency divider 12 through its stages at a rate controlled by the
output pulses from pulse frequency divider 11 in phase with the
operation of shift register 14. The shift register 18, in an
identical manner as shift register 14, operates to provide locator
pulses which are stepped sequentially through each of its stages,
with each stage corresponding to one time slot in a total time
frame of at least 97. In practice, about 128 time slots would be
used with only 97 latching circuits so that a pulse delayed 48
positions from the top key on the manual (time slot 61) will fall
in an empty latching slot and not fall into a slot assigned to the
low end of the keyboard. For example, in 97 units of time, one
locator pulse will appear sequentially at the output of each stage.
The time slot position of the locator pulse in shift register 14
will therefore correspond exactly to the locator pulse time slot
position in shift register 18 because the two registers are in
phase. A plurality of latching means 20, at least one for each
stage of shift register 18, senses the presence of a locator pulse
when it appears at the output of its associated register stage. The
existence or non-existence of a locator pulse at the particular
shift register stage output is compared against the existence or
non-existence of a locator pulse on a latching line 17. When
coincidence of pulses occurs, the latching means 20 activates a
corresponding voice in the keyboard instrument. When one of the two
locator pulses do not appear simultaneously, the associated voice
is not sounded.
To accomplish the above electronically, each latching means 20 is
comprised of one AND gate "A", one NOT gate "N", and a flip-flop
19. Each output stage of shift register 18 is connected to one
input of a respective AND gate "A" and the NOT impulse of a NOT
gate "N". The AND gate output is connected to the set terminal of
flip-flop 19 with the output of the NOT gate connected to the reset
terminal of flip-flop 19. For each pitch to be keyed on the main
keyboard, there is a corresponding flip-flop 19 along with one AND
gate "A" and one NOT gate "N". The output from the flip-flop may be
connected to a standard music voicer circuit 40 for converting the
signal corresponding to a depressed key into an audible note by
means of a speaker 50. Also connected as independent inputs to an
input of the AND gate "A" and the NOT gate "N" is the signal from
pulse frequency divider 11. In operation, the pulses received on
line 17, which pulses will be called latching pulses, are fed as
inputs to the AND gate and to the NOT gates. A coupler line 21
feeds locator pulses to inputs of the AND gates and the NOT
gates.
In operation, if no key 15 is depressed, then there will be no
locator pulses on the coupler line 21. With this condition, each of
the AND gates contain in successive time slots an ON state from the
latching pulse on line 17 and an OFF state from the coupler line.
Because the coupler line is connected to a NOT input, each NOT gate
will, in turn, provide a pulse to its associated reset terminal of
its flip-flop. Thus, if no key is depressed, all the flip-flops 19
are, in turn, placed in their OFF states. When a key is depressed,
a locator pulse will appear on coupler line 21. When the locator
pulse on coupler line 21 occurs simultaneously with an output pulse
from a stage of shift register 18 along with a latching pulse on
line 17, the particular NOT gate will not provide a pulse to the
reset terminal. But the AND gate will have pulses on all its
inputs, therefore, a pulse will be passed on to the flip-flops set
terminal to place the flip-flop in its ON state.
Inserted between terminals 16 and 22 is a multiplexed pitch
generator 25 which functions to selectively reposition the locator
pulses from terminal 16 into newly selected timing slots. The new
slot positions correspond to the generation of a new coupled note.
In this particular embodiment, it has been assumed that the first
12 pulse locations in the keyboard multiplexed sequence correspond
to octave 1. This octave cannot actually be played from a standard
keyboard because it is an octave below the bottom octave of the
keyboard. The reason for allowing for these additional time slots
is to allow for 16' pitch generation and a 16' coupler. The
multiplexed pitch generator 25 is comprised of a shift register 31
having at least 48 stages. Outputs are not taken from every stage,
but are taken from the stages corresponding to the numbers
contained within the shift register 31, namely, 12, 16, 19, 24, 31,
36, 40, 43 and 48. Stops (keys) 32 connect the output of the
selected stages to the input of a summing circuit 24 when actuated.
For example, if the stop corresponding to 8' is closed, the output
from the 12th delay stage of shift register 31 is fed to the input
of summing means 24. An additional stop (key) 23, corresponding to
the 16' pitch is fed to another input of summing means 24 such that
when stop 23 is closed, the output locator pulses from terminal 16
are fed directly to terminal 22 at the output of the pitch
generator, thereby bypassing entirely the multiplex pitch generator
25. Again, the numerals appearing for each stage of the shift
register correspond to the time slot delays introduced by the shift
register preceding the particular output point. All of these delays
are measured from the input to the shift register. For example, if
the 8' tap switch is closed, a pulse will appear on the output for
each note keyed on the manual. If, for example, the 22/3 ' tap
switch is also closed, then a pulse will appear for the 8' keyed
note and a companion pulse will also appear for the 22/3 ' keyed
note. In this fashion, the described subsystem which will be called
a unification subsystem, can generate the 10 most used pitches for
a unified organ. The system thus far shown is complete for one
keyboard.
In FIG. 2, there is shown an intermanual unison coupler system for
three keyboards which system is comprised of three identical
systems as shown in FIG. 1 except that there is no need to
duplicate the basic clock 10, pulse frequency divider 11, and
frequency divider 12 because these units can service all three
systems. The outputs at points D and E are, therefore, fed to the
corresponding points in the other keyboard circuits to eliminate
duplication of the clock and frequency dividers. Cross-coupling is
accomplished as shown by the use of switches 37, 38 and 39. For the
unison couplers there is utilized three identical multiplexed pitch
generators 25, 41 and 42, with the output of pitch generator 25
being connectable by means of switches 37 or 38 to an input of
summer 43 or 46, respectively. The other input of summer 44 is
connected to the output of pitch generator 41. The output of pitch
generator 42 is connected to one input of summer 44. The other
input of summer 44 is connectable by switch 39 to the output of
summer 43. In turn, the output of summer 44 is connected to the
other input of summer 46. In operation, if, for example, switch 37
is closed, the output from keyboard 1 is fed to the comparing means
45 of keyboard 1, but, in addition, is also fed to and added to the
output from keyboard 2, which output is used to activate the
comparing means 47 associated with keyboard 2. The operation is the
same for switch 38 in that it couples the output of keyboard 1 to
the output of pitch generator 42 which, in turn, feeds the
comparing means 48 of keyboard 3. Switch 39, in a similar manner,
feeds the output of pitch generator 41 to the comparing means 48
associated with keyboard 3. The outputs of comparing means 47 and
48 are connected to the tone generating system 40. In some
applications it may be desirable to have three separate tone
generating systems, each activated by an individual keyboard.
Referring now to FIG. 3, an intramanual coupler 51 is shown
connected between the output of multiplexed pitch generator 25 and
terminal 22. The intramanual coupler 51 is comprised of a shift
register 52 which is identical in construction to shift register
31, with switches 53 connectable to the outputs of the 12th, 24th
and 36th time slots (output stages). These outputs correspond to
the 16', 8' and 4' pitches, respectively. Each of the three
switches are connected directly to the output terminal 22. With the
multiplexed pitch generator 25 preceding the intramanual coupler,
it is necessary, in order to permit a 16' intramanual coupler
operation, that the keyboard be multiplexed at a 32' frequency, or
two octaves below unison pitch. The reason for this is that the
multiplexed pitch generator requires an octave leeway to generate a
16' unified pitch while the intramanual coupler requires an
additional octave leeway to allow for a 16' intramanual
coupler.
Referring now to FIG. 4, an intercoupler is shown which utilizes
the system of FIG. 2. The system of FIG. 2 is modified by the
insertion of intermanual nonunison couplers 60, 61 and 62 at the
outputs of the multiplexed pitch generators 25, 41 and 42. The
intermanual unison-nonunison coupler 60 is shown comprised of a
shift register 61 which is identical to shift registers 31 and 52.
The outputs of shift register 61 are taken from the 12th, 24th and
36th time slots to correspond to the 16', 8' and 4' pitches,
respectively. Two separate output terminals are provided, labeled A
and B, which output terminals are connectable by separate switches
63 and 64 to the 16' output. A similar switch configuration is
provided for the 8' and 4' output. The arrangement is such that,
for example, a 16' pitch output signal can appear on the A and B
output terminals simultaneously if both switches 63 and 64 are in
the closed position. The two sets of switches for each of the used
register output stages is required so that the intermanual and
intramanual couplers will be independent. That is, if, for example,
a 4' coupler (output at A) is drawn on an intramanual coupler, this
will in no way affect the intermanual coupling (output at B) from
the same keyboard. To provide for complete keyboard coupling,
switches 65 and 67, when closed, feed the signal from the A
terminal of intermanual unison-nonunison coupler 60 to an input of
summer 43 and summer 44, respectively, to be summed with the output
of coupler 61 and/or 62. In addition, the B terminal output is
connectable by means of switch 66 as an input to summer 43. In
addition, switch 69 connects the output of summer 43 to the input
of summer 44 when in a closed position. Switch 68 in its closed
position is used to connect the B terminal output from unison
coupler 61 to an input of summer 44.
Referring now to FIG. 5, in conjunction with FIG. 1. FIG. 5
illustrates a unified mixture generator 70 comprised of a shift
register 71 having switches 72 connectable between an output
terminal and the output stages corresponding to 12th, 19th, 24th,
31st, 36th, 43rd, 48th and 55th time slots, respectively. The
switches 72, when actuated, correspond to the 4', 22/3 ', 2',
1.sup.- ', 1', 2/3', 1/2', and 1/3', respectively. When one or more
switches are closed, the information stored in the associated shift
register stage is passed to the output of generator 70. The input
of generator 70 is taken from the 8' pulse stage of shift register
31 (FIG. 1) via switch 73. The output signal of mixture generator
70 is fed to point F and the organ voicer 40.
In FIG. 6, five mixture shift registers 70, one for each octave of
the instrument, are connected to receive independent outputs from
the octave time gate means 74. The output of each of the registers
70 is summed together in summing circuit 75 and fed to point F in
the system. The input to the octave gate means is received from the
8' stage of shift register 31 via switch 73, when it is closed. The
octave times gates 74 also receive the basic clock pulses from the
basis clock 10. In operation, the 8' pulses received at the input
of the octave time gate means 74 are fed to each of the five octave
outputs sequentially in turn. The basic clock pulses are counted
and for each octave quantity of pulses the input to the octave time
gate means is connected to the input of a mixture shift register
70. The process continues cycling through each shift register in
turn for so long as there are 8' pulses present on the input of
gate means 74.
Referring to FIG. 7 wherein is shown an alternate embodiment of a
mixture generator 76, which could be substituted for the mixture
generator of FIG. 6. The mixture generator 76 is comprised of a
multistage shift register 77 having outputs at the numerically
designated staged. For example, at stages 12, 19, 24, 31, 36, 43,
48 and 55. Five logic gates 78 are used, with each gate
corresponding to a desired octave. For the embodiment shown, these
are octaves 2 through 6.
The following chart lists the input connections to the logic gates
78 from the shift register 77 and the octave timing means 79.
Octave Delay Logic Gate Footages Outputs of Shift Register 77
__________________________________________________________________________
2 1, 2/3, 1/2, 1/3 36, 43, 48, 55 3 11/3, 1, 2/3, 1/2 31, 36, 43,
48 4 2, 11/3, 1, 2/3 24, 31, 36, 43 5 22/3, 2, 11/3, 1 19, 24, 31,
36 6 4, 22/3, 2, 11/3 12, 19, 24, 31
__________________________________________________________________________
The outputs of logic gates 78 are summed together in summer 80. The
summed output is then fed to terminal F in FIG. 2.
The octave timing generator 79 receives multiplex period pulses
from the output of frequency divider 12 and timing pulses from
pulse frequency divider 11.
The octave timing generator 79 has five outputs corresponding to
the octaves 2 through 6 which are connected to the inputs of
corresponding logic gates 78.
In FIG. 8, the octave timing pulses a through f are shown for the
five octaves. When an octave pulse is in its true state, the gate
corresponding to that octave pulse passes the pulses collected from
the shift register. When an octave pulse is in its false state, the
corresponding gate blocks the pulses from the shift register.
While there has been disclosed what is considered to be the
preferred embodiment of the invention, it will be manifest that
many changes and modifications may be made therein without
departing from the essential spirit of the invention.
* * * * *