U.S. patent number 3,786,167 [Application Number 05/280,501] was granted by the patent office on 1974-01-15 for musical instruments.
Invention is credited to Arthur R. Bonham, James J. Borell.
United States Patent |
3,786,167 |
Borell , et al. |
January 15, 1974 |
MUSICAL INSTRUMENTS
Abstract
Musical instruments playable in duet fashion by one player
includes a stringed instrument with segmented frets. A control
system for the other instrument includes a control circuit for each
string and which has actuating circuits that are associated with
the open and keyed string tones playable on the string. The
actuating circuits associated with the second and higher string
keying positions are enabled by simultaneous string contact with
adjacent fret sections, and simultaneous string contact with a
plate and fret segment at the first position serves to enable the
actuating circuit associated with the first string keying position.
A disabling circuit has components associated with each actuating
circuit and which disable the associated actuating circuit in
response to output signals of the actuating circuits associated
with the higher keying positions. Open tone sensing circuits are
avoided in one embodiment especially designed for chord playing
players of the stringed instrument and in which simultaneous
signals from a predetermined number of disabling circuits that are
enabled by simultaneous keying of different strings serve to
control an auxiliary circuit to enable the actuating circuits
associated with the open tones of the unkeyed strings.
Inventors: |
Borell; James J. (Kissimmee,
FL), Bonham; Arthur R. (Orlando, FL) |
Family
ID: |
23073344 |
Appl.
No.: |
05/280,501 |
Filed: |
August 14, 1972 |
Current U.S.
Class: |
84/701; 84/722;
84/DIG.30; 84/708; 84/712; 984/346; 984/347 |
Current CPC
Class: |
G10H
1/342 (20130101); G10H 1/36 (20130101); Y10S
84/30 (20130101) |
Current International
Class: |
G10H
1/36 (20060101); G10H 1/34 (20060101); G10h
003/00 (); G10h 005/00 () |
Field of
Search: |
;84/1.16,DIG.30,170,171,263 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tomsky; Stephen J.
Assistant Examiner: Witkowski; Stanley J.
Attorney, Agent or Firm: Martin; Roger L.
Claims
What is claimed as new and what it is desired to secure by Letters
Patent of the United States is:
1. The combination comprising
a. a first musical instrument which includes
1. a keyboard having a nut end, and
2.
2. musical strings that are keyed against said keyboard at string
keying positions when keyed string tones are played on said
strings,
b. a second musical instrument having tone producing means for
producing audible tones that correspond in pitch to keyed string
tones which are playable on said strings, and
c. a control circuit for controlling said tone producing means to
simultaneously produce an audible tone that corresponds in pitch to
a keyed string tone being played on one of said strings,
said control circuit comprising
1. a plurality of fret segments that are mounted on said keyboard
and spaced apart one adjacent to the next in a row which underlies
said one string and which commencing at said nut end extends
remotely of said nut end, and
2. a plurality of actuating circuits that are connected to the
respective fret segments and to said tone producing means,
each of said fret segments being located at a respective one of
said string keying positions and being arranged for contact by said
one string when said one string is keyed against the keyboard
thereat,
said one string having string tones which are playable thereon and
which include
1. an open string tone, and
2. a plurality of keyed string tones of progressively higher pitch
than said open string tone,
said keyed string tones of progressively higher pitch being
respectively associated with said fret segments and being playable
on said one string when said one string is keyed into contact with
the fret segment associated therewith,
each of said actuating circuits being to actuate said tone
producing means to produce an audible tone that corresponds in
pitch to the respective one of said keyed string tones of
progressively higher pitch that is associated with the fret segment
connected thereto,
said actuating circuits including
a first circuit for actuating said tone producing means to produce
an audible tone that corresponds in pitch to the keyed string tone
that is associated with the one of said fret segments connected to
said first circuit,
said first circuit being responsive to simultaneous contact by said
one string with said one fret segment and with another of said fret
segments that is located next adjacent thereto in said row, and
the other of said fret segments being further located between said
nut end
and said one fret segment. 2. The combination in accord with claim
1
where said first circuit has an output signal,
where said control circuit comprises
a second circuit which is connected to said actuating circuits,
and
where said second circuit is controlled by said first circuit and
responsive to said output signal to disable the actuating circuits
which are connected to the fret segments located between said nut
end and said one fret segment.
3. The combination in accord with claim 2
where said control circuit comprises
a third circuit that is connected to said tone producing means and
responsive to the playing of said open string tone on said one
string for actuating said tone producing means to produce an
audible tone that corresponds in pitch to said open string tone,
and
where said second circuit is connected to said third circuit and
also disables said third circuit in response to said output
signal.
4. The combination comprising
a. a first musical instrument which includes
a keyboard, and
musical strings that are keyable against said keyboard,
b. a second musical instrument having
tone producing means for producing audible tones that correspond in
pitch to string tones playable on said strings, and
c. a control system that includes
a plurality of control circuits that are respectively associated
with said strings,
each of said strings having string tones which are playable thereon
and which includes
1. an open string tone, and
2. a plurality of keyed string tones of progressively higher pitch
than said open string tone,
each of said control circuits being connected to said tone
producing means for controlling said tone producing means to
produce audible tones that correspond in pitch to string tones
playable on a respective one of said strings and including
a first circuit component which is connected to said tone producing
means for actuating said tone producing means to produce an audible
tone that corresponds in pitch to the open string tone of said
respective one string, and
a second circuit component which is connected to said first circuit
for disabling said first circuit component when said respective one
string is keyed against said keyboard,
said second circuit component having an output signal when said
first circuit component is disabled, and
said combination comprising
an auxiliary circuit connected to receive the output signals from
the second circuit components of said control circuits and being
responsive to the simultaneous receipt of the output signals from a
predetermined number of said control circuits for enabling the
first circuit components of the control circuits associated with
the unkeyed ones of said strings,
said predetermined number being less than the total number of
strings.
5. The combination in accord with claim 4
where each of said control circuits includes
a plurality of fret segments that are mounted on said keyboard and
spaced apart one adjacent the next in a row which underlies said
respective one string and which commencing at said nut end extends
remotely of said nut end, and
a group of actuating circuits that are connected to the respective
fret segments and to said tone producing means,
each of said fret segments being located at a respective one of
said string keying positions and being arranged for contact by said
respective one string when said respective one string is keyed
against the keyboard thereat,
the keyed string tones of progressively higher pitch playable on
said respective one string being respectively associated with said
fret segments and being playable on said respective one string when
said respective one string is keyed into contact with the fret
segment associated therewith,
each of said actuating circuits being to actuate said tone
producing means to produce an audible tone that corresponds in
pitch to the respective one of said keyed string tones of
progressively higher pitch that is associated with the fret segment
connected thereto,
said actuating circuits including
a third circuit for actuating said tone producing means to produce
an audible tone that corresponds in pitch to the keyed string tone
that is associated with the one of said fret segments connected to
said third circuit,
said third circuit being responsive to simultaneous contact by said
respective one string with said one fret segment and with another
of said fret segments that is located next adjacent thereto in said
row,
the other of said fret segments being located between said nut end
and said one fret segment, and
where said second circuit is connected to said actuating circuits
and controlled to respond to said third circuit and disable said
first circuit and the actuating circuits which are connected to the
fret segments between said nut end and said one fret segment.
6. The combination comprising
a. a first musical instrument which includes
1. a keyboard and
2. musical strings that are keyed against said keyboard in playing
keyed string tones thereon,
b. a second musical instrument having tone producing means for
producing audible tones that correspond in pitch to string tones
playable on said strings, and
c. a plurality of control circuits that are respectively associated
with said strings,
each of said control circuits being connected to said tone
producing means for controlling said tone producing means to
produce audible tones that correspond in pitch to string tones
playable on the respective one of said strings that is associated
with the control circuit,
said respective one string having string tones which are playable
thereon and which includes
a. an open string tone, and
b. a plurality of string tones of progressively higher pitch than
said open string tone,
said control circuit comprising
a first circuit component connected to said tone producing means
for actuating said tone producing means to produce an audible tone
that corresponds in pitch to the open string tone playable on said
respective one string, and
a second circuit component which is connected to said first circuit
component for disabling said first circuit component when said
respective one string is keyed against said keyboard,
said second circuit component having an output signal when said
first circuit component is disabled, and
an auxiliary circuit which is connected to receive the output
signals from the second circuit components of said control circuits
and which is responsive to the simultaneous receipt of the output
signals from a predetermined number of said control circuits for
enabling the first circuit components of said control circuits
which are associated with the then unkeyed ones of said
strings,
said auxiliary circuit being connected to each of the first circuit
components of said control circuits, and
said predetermined number being less than the total number of said
strings.
7. The combination comprising
a. a guitar which includes a keyboard having a nut end, and strings
that are keyed against the keyboard at string keying positions in
playing keyed string tones on said strings,
b. an electronic organ having tone signal generators, and
c. a control circuit connected to said generators for controlling
said generators to simultaneously produce a tone signal that is
translatable to an audible tone which corresponds in pitch to a
string tone being played on one of said strings, said control
circuit comprising
1. a plurality of fret segments that are mounted on said keyboard
and spaced apart one adjacent to the next in a row which underlies
said one string and which commencing at said nut end extends
remotely of said nut end, and
2. a plurality of actuating circuits for actuating the respective
generators,
each of said fret segments being located at a respective one of the
string keying positions and being arranged for contact by said one
string when said one string is keyed against the keyboard
thereat,
said one string having string tones that are playable thereon and
which include
an open string tone, and
a plurality of keyed string tones of progressively higher pitch
than said open string tone,
said keyed string tones of progressively higher pitch being
respectively associated with said fret segments and being playable
on said one string when said one string is keyed into contact with
the fret segment associated therewith,
said plurality of actuating circuits comprising
a group of circuits that are connected to the respective fret
segments,
each of the grouped circuits being connected to a respective one of
said generators for actuating the respective one generator to
produce a tone signal that is translatable to an audible tone which
corresponds in pitch to the one of said keyed string tones that is
associated with the fret segment connected thereto,
said grouped circuits including
a first circuit for actuating the generator connected thereto to
produce a tone signal that is translatable to an audible tone which
corresponds in pitch to the keyed string tone that is associated
with the one of said fret segments connected to said first
circuit,
said first circuit being responsive to simultaneous contact by said
one string with said one fret segment and with another of said fret
segments that is located next adjacent thereto in said row, and
the other of said fret segments being further located between said
nut end and said one fret segment.
8. The combination in accord with claim 7
where said first circuit includes first gate means having an output
signal,
where the generator connected to said first circuit is connected to
receive and actuated during the receipt of said output signal,
and
where said first gate means is enabled during said simultaneous
contact to produce said output signal.
9. The combination in accord with claim 8
where said generators include
a first generator that is actuatable to produce a tone signal that
is translatable to an audible tone which corresponds in pitch to
the open string tone playable on said one string,
where said plurality of actuating circuits comprise
a second circuit for actuating said first generator and which is
responsive to and has means for sensing said open string tone,
where said control circuit comprises
a third circuit connected to said plurality of actuating circuits
and having second gate means operating under the control of said
first gate means for disabling said second circuit and the grouped
circuits which are connected to the fret segments between said nut
end and said one fret segment,
said second circuit and the grouped circuits which are connected to
the fret segments between said nut end and said one fret being
controlled by said second gate means, and
said second gate means being connected to receive said output
signal and being enabled during the receipt of said output
signal.
10. The combination in accord with Claim 8
where said control circuit comprises
second gate means operating under the control of said first gate
means for disabling the grouped circuits which are connected to the
fret segments between said nut end and said one fret segment,
said second gate means being connected to receive and being enabled
during receipt of said output signal.
11. The combination comprising
a. a guitar having a keyboard and strings that are keyable against
said keyboard,
b. an electronic organ having tone signal generating means, and
c. a plurality of control circuits that are respectively associated
with said strings for controlling said generating means to
simultaneously produce tone signals that are translatable to
audible tones which respectively correspond in pitch to keyed
string tones being played on said strings,
each of said strings having string tones which are playable thereon
and which include an open string tone and a plurality of keyed
string tones of progressively higher pitch than said open string
tone,
each of said control circuits being connected to said generating
means and including
1. a first circuit for actuating said generating means to produce a
tone signal translatable to an audible tone corresponding in pitch
to the open string tone playable on the string associated with the
control circuit, and
2. a second circuit for disabling said first circuit when a keyed
string tone is being played on the string associated with said
control circuit and having an output signal when said first circuit
is disabled,
said first circuit being connected to receive said output signal
from said second circuit, and
an auxiliary circuit which is connected to receive the output
signals from the second circuits of said control circuits and which
is responsive to simultaneous receipt of a predetermined number of
said output signals from said second circuits for enabling the
first circuits of the control circuits that are associated with the
unkeyed ones of said strings.
12. The combination in accord with claim 11 where said
predetermined numbers is three.
Description
BACKGROUND OF THE INVENTION
This invention relates to musical instruments and more particularly
to control systems for musical instruments which may be played in
duet fashion by a single player of but one of the instruments.
Systems for controlling the operation of the tone producing
components of one musical instrument from the keyboard of another
musical instrument of the string type so that both instruments may
be played in duet fashion by one person are known. Prior to the
invention disclosed in Borell U.S. Pat. No. 3,465,086, systems for
controlling the operation of the tone producers of one musical
instrument from the keyboard of a second musical instrument of the
string type were unsatisfactory because special finger
manipulations were required of the player of the stringed
instrument in order to actuate the tone producing components of the
other instrument and which were associated with the open string
tones of the stringed instrument. Borell in the aforementioned
patent, discloses several different means for sensing the
mechanical movement of the string when the open tone is played
thereon and of then actuating the associated tone producing
components of the other instrument.
The aforementioned patentee also shows various switching
arrangements used in actuating the tone producing components
associated with the keyed string tones, and as the art has
developed in practice, it has been found that switching systems
involving the use of auxiliary switches having movable components
that are encountered by the player during the string keying process
are less than fully satisfactory. The main objection has been that
the movable component imparts an abnormal feeling to the players
fingers as the strings are keyed. As a consequence, the art in
practice is developing around the use of switching systems that
rely on an electrical contact being made between the string and a
fret associated with the keyed string tone involved in playing the
stringed instrument. The frets of the instruments in such cases are
bifurcated or segmented and composed of electrically conductive
sections or segments that are associated with the respective
strings of the instrument. The circuits actuating the tone
producing circuits associated with the fret sections rely on the
completion of an energized circuit which involves the fret section
and a string being keyed in order to produce the desired keyed
string tone.
One of the difficulties which has been encountered in developing a
switching system that is founded on the need for an electrical
contact being made between the string and a fret segment arises
from the fact that the player of the stringed instrument, in
playing a keyed string tone at a string keying position, depresses
the string into contact with the keyboard at a point which is
located between the fret section associated with the keying
position and the fret section associated with the next lower keying
position. As a result, the string contacts both the desired fret
section and the adjacent fret section associated with the next
lower tone playable on the string. Although disabling circuits,
such as the arrangement shown in the aforementioned patent, may be
used to disable the circuitry associated with the adjacent keying
position, many stringed instrument players have a tendency to slide
the finger along the string in establishing the keyed string
position. This tendency frequently causes initial contact between
the string and fret section that is associated with the lower keyed
string tone before string contact with the desired fret section is
secured. This, of course, results in a momentary discord emanation
from the musical instrument being controlled by the circuitry and
of course, is unsatisfactory in practice.
The skills of many guitar players are also somewhat limited to the
playing of chords as opposed to the playing of individual tones in
an orderly sequence. In this chord-type of instrument play on a
guitar for example, it is usual practice to key three or four of
the strings of the guitar in accord with the keyed string
requirements for the chord and to simultaneously strum all of the
strings of the guitar when the chord is being played. The open
tones of the unkeyed strings under such circumstances are
accordingly played by the guitar player and systems which utilize
the open tone sensing circuits such as those disclosed in the
aforementioned patent for playing the tones associated with the
unkeyed strings are admirably suited to securing from the second
instrument all tones corresponding in pitch to the open string
tones while the chord is being played by the player of the stringed
instrument. However the need for locating the sensors in close
proximity to the strings of the stringed instrument involves costly
modifications of the instrument structures and, accordingly, there
is a desire for a less costly control system for actuating the tone
producers of the second instrument which are associated with the
open string tones emanating from the stringed instrument when
chords are being played.
STATEMENT OF THE INVENTION
One aspect of the invention has to do with the problems with
discord which result from the playing of a key string tone and
which are caused by the premature encounter of the string with the
adjacent fret section associated with the lower keyed string tone
playable on the string. In accord with this aspect of the invention
provisions are made for enabling the switching circuit to actuate
the tone producing components associated with the keyed string tone
only when the string is in contact with both the fret section
associated with the desired keyed string tone and the adjacent fret
section associated with the lower keyed string tone at the keying
position on the keyboard. The tone producing component of the
second instrument is thus only responsive to simultaneous string
contact with the two fret sections involved at the keying position
so that the discord problem is avoided. At the first position for
keying a string of the stringed instrument, an auxiliary contact is
provided and, as will be subsequently seen, circuitry is also
provided which disables the switching circuits associated with the
open tone and keyed string tones associated with the lower numbered
positions for keying the string.
Another aspect of the invention has to do with the provision of
circuitry which responds when a predetermined number of strings on
the stringed instrument are being keyed and actuates the tone
producing components of the second instrument that are associated
with the open string tones of the unkeyed strings of the stringed
instrument, again through the use of suitable gating logic. The
circuitry, as will be subsequently seen, is responsive to the
conditioning circuit output of the control circuit for the organ
control system and is designed to key the tone producers associated
with the open string tones of the unkeyed strings of the stringed
instrument and in a circuit that avoids the need for open string
tone sensors.
The novel features which are believed to be characteristic of this
invention are set forth with particularity in the appended claims.
The invention, itself, however, both as to its organization and
method of operation, together with further objects and advantages
thereof, may best be understood by reference to the following
description taken in connection with the accompaning drawings, in
which:
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 diagrammatically illustrates certain components of an
electronic organ together with certain components of a system for
controlling the organ from the keyboard of a six-string musical
instrument of the guitar type;
FIG. 2 shows a neck fragment at the nut end of the guitar embodying
components diagrammatically illustrated in FIG. 1; and
FIG. 3 shows a circuit modification of the embodiment illustrated
in FIG. 1, as modified to eliminate open string tone sensing
components and to incorporate circuitry for actuating organ tones
associated with open string tones of unkeyed strings to be
selectively played when chords are being played on the guitar.
DESCRIPTION OF EMBODIMENTS
Reference is now made to FIGS. 1 and 2 and wherein certain aspects
of the invention are illustrated as embodied in a combination of
musical instruments that include a six-string guitar 11 and an
electronic organ. In this instance, the signal generators of the
electronic organ 12 are controlled from the keyboard 13 of the
guitar 11 by means of a control system 14 that responds when the
strings of the guitar are keyed at the various keying positions to
electrical contact made between the frets and strings of the
guitar.
The strings 15 of the guitar 11 illustrated in the drawings are
strung between an electrically nonconductive bridge 16 and an
electrically nonconductive nut 17. The frets 18 underlie and are
located spacedly below the strings 15 and are arranged transversely
and spaced part along the keyboard 13. The frets in this instance
are segmented with each fret being composed of electrically
conducted fret sections or segments 19 that underlie the respective
strings and are spaced apart from the other conductive segments of
the fret by electrically insulating segments designated at 20. The
neck of the guitar, as seen in FIG. 2, is composed of upper and
lower sections 22 and 23 that are secured together and shaped to
provide an elongated opening 24 within the neck that serves to
house wiring components associated with the organ control system
14.
The organ 12 is shown in the illustration as including a plurality
of tone signal generators 25 that are actuated in accord with the
condition of control system 14. The signal generators have outputs
26 that are fed through appropriate lead lines designated at 58,
58a, 58b, etc., to the input lead 27 of an amplifier 28 when the
signal generators are actuated. The output 29 of the organ
amplifier 28 is in turn fed to a reproducer or loudspeaker 30 that
translates the output signals into appropriate audible tones, as
will be apparent to those skilled in the art. Only the tone signal
generators associated with the sixth string of the guitar are
generally illustrated in FIG. 1. It will be apparent however that
the organ has other tone signal generators and that the oscillator
may also be associated with the control circuits of the other
strings and thus capable of actuation when the same tone is played
on another string. The tone signal generators illustrated are of
the type that are energized when actuated but it will be apparent
that signal generators which are continuously energized may be used
and that their actuation under such circumstances will complete a
circuit feeding the signals to the amplifier and audio output.
The system 14 for controlling the organ in accord with the keyed
and open string tones that are played on the guitar 11 includes a
separate control circuit for each string of the guitar. The
separate control circuits for the individual muscial strings that
are identified by roman numerals I through VI in the drawings, are
designated at 31 through 36 respectively. The control circuits 31
through 36 are generally arranged in parallel circuits that are in
turn connected in series through a single pole, single throw
control switch 37 to a source 38 establishing a negative potential
condition. An electrical lead 39 is also connected to source 38
through switch 37 and each of the electrically conductive musical
strings I through VI inclusive is electrically connected to lead 39
as by means of a suitable electrical lead 40 that is tapped into
line 39.
It may be well at this point to state that the expressions
"negative" and "positive" as used herein with reference to signals
and potential conditions should be understood as having reference
to relative voltage levels which are respectively lower and higher
by comparison. Thus a negative signal or potential condition should
be understood as having reference to a voltage level that may be
either negative or positive but which is nevertheless lower by
comparison to a signal or potential condition indicated herein as
being positive.
The control circuits 31 through 35 associated with strings I
through V are similar to the control circuit 36 which is
illustrated for string VI and hence the following detailed
description concerning control circuit 36 should be understood as
basically also explaining the composition of and operation of
circuits 31 through 35.
Control circuit 36 includes a transducer 41 for sensing vibrational
movement of string VI when the open string tone is being played
thereon. It also includes the electrically conductive fret segments
41a, 41b, 41c, etc., that are associated with the first and higher
positions for keying string VI against keyboard 13. The fret
segments 41a, 41b, etc. associated with string VI are spaced apart
one adjacent the next in a row that underlies the string VI and are
contacted by string VI when the string is keyed against the first,
second and higher keying positions along the keyboard 13. The keyed
string tones that are playable on the string VI are progressively
higher pitched than the open string tone that may be played on the
string and these keyed string tones are played, of course, by
keying the string with the finger against the keyboard at the first
and subsequent string keying positions. The tone signal generators
that are associated with the open string tone for string VI and the
tones obtained through keying the string at the first and higher
keying positions are respectively designated at 42, 42a, 42b, etc.
The actuating circuits for the signal generators 42, 42a, 42b,
etc., are designated in the drawings at 43, 43a, 43b, 43c, etc.,
and each is associated with a tone playable on string VI. Each of
these circuits 43, 43a, 43b, etc., has a three input position
positive "nor" gate with an output signal that is fed through a
diode to the tone signal generator associated with the circuit. The
"nor" gates are designated at 44, 44a, 44b, etc., while the
respective output signals are designated at 45, 45a, 45b, etc., and
the diodes at 46, 46a, 46b, etc. When the input condition at each
of the input positions of a "nor" gate is negative, the gate opens
and provides a positive output signal.
Transducer 41 generates a negative output signal 47 when the open
tone vibration of string VI is sensed, and this signal 47 is fed to
the b input position of gate 44. This signal 47 is tapped and also
delivered to the a input position for gate 44 as by lead 48. The
normal condition at the a and b inputs of gate 44 is positive and
hence if the gate is conditioned with a negative potential at the c
input, as will be subsequently seen, the gate is opened by the
delivery of the negative output signal to the a and b
positions.
The fret segments 41a, 41b, 41c, etc., are respectively associated
with the first, second and higher positions for keying string VI
and are electrically connected by respective leads 47a, 47b, 47c,
etc., to the b input positions for the respective gates 44a, 44b,
44c, etc., as seen in the drawings. Circuit 36 has a small
electrically conductive plate 49 that underlies string VI in the
first position for keying the string. This plate 49 is electrically
connected to the a input position of gate 44a by lead 49a. The a
input positions for the gates 44b, 44c, etc., associated with the
second and higher keying positions for string VI are connected by
leads 49b, 49c, 49d, etc., to the leads 47a, 47b, 47c, etc., that
are associated with the next lower keying positions as seen in FIG.
1.
In addition to actuating circuits 43, 43a, 43b, 43c, etc., circuit
36 includes a conditioning circuit 50 for conditioning the
actuating circuits 43, 43a, 43b, etc., for the reception of gate
opening signals and for disabling the actuating circuits that are
associated with the lower tones playable on the string when the
string is keyed at one of the fret positions. The conditioning
circuit 50 includes a plurality of series arranged two position
positive "or" gates 51, 51a, 51b, etc. The outputs of these "or"
gates are connected by leads 52, 52a, 52b, etc., to the c input
positions for gates 44, 44a, 44b, 44c, etc., as seen in the
drawings. The positive "or" gates provide a positive output signal
when a positive potential condition is established at either of the
input terminals, and the output signals of gates 51a, 51b, etc.,
are tapped by leads 53a, 53b, 53c, etc., so as to also deliver the
output signal to the a position of the "or" gate associated with
the next lower tone playable on string VI, as seen in the drawings.
Each "or" gate is associated with one of the actuating circuits
and, except for the "or" gate 56 associated with the actuating
circuit at the highest string keying position, the b positions of
the "or" gates are connected by leads 54a, 54b, 54c, to receive the
output signal of the "nor" gate that is associated with the next
higher tone playable on string VI. The b input of gate 56 on the
other hand is tied to the a input lead 55 so as to receive the
negative output from source 38 through switch 37.
When switch 37 is placed in the closed position, a negative
potential condition is established along each of the electrically
conductive musical strings I through VI. Closure of switch 37 also
establishes a negative condition at the a input position of each of
the "or" gates 51, 51a, 51b, etc., and by virtue of the line taps
54a, 54b, 54c, etc., and the tie-in 55 for gate 56, a negative
potential condition is established at the b position for each of
the "or" gates in the conditioning circuit 50. Under these
circumstances a negative potential condition is established at each
of the c positions for the "nor" gates 44, 44a, 44b, etc., and each
of the circuits 43, 43a, 43b, etc., is readied and conditioned to
actuate the tone signal generators when the other inputs of the
gate receive negative signals.
Under the existing ready conditions, if string VI is strummed to
provide the open string tone associated with the string, transducer
41 senses the vibrational movement and generates a negative signal
that is passed to the a and b input positions of gate 44. In view
of the readied condition of the gate 44, this sends a positive
signal 45 via the diode 46 to signal generator 42 and in turn
actuates generator 42 to provide an output signal 57. Signal 57 is
fed by lead 58 to input line 27 of amplifier 28. The amplified
output signal 29 is then delivered to loudspeaker and translated
into an open tone signal corresponding in pitch to that of the open
string tone played on string VI.
When string VI is keyed at the first position to provide the keyed
string tone associated with the fret segment 41a at this position,
the string VI is keyed against the keyboard and assumes a position
such as designated at 59. Under these circumstances, string VI is
in electrical contact with plate 49 and also with the fret segment
41a. The electrical contact between string VI and segment 41
establishes a negative potential condition at the b position of
"nor" gate 44a while the contact between string VI and plate 49
establishes a negative potential condition at the a position of
gate 44a. With gate 44a readied by the conditioning circuit 50 that
provides a negative potential at the c input of the gate, the gate
is opened under these circumstances and delivers a positive output
signal 45a via diode 46a to signal generator 42a. When gate 44a
opens a positive signal is also delivered to the b position of "or"
gate 51, and this opens the gate and delivers a positive signal to
the c terminal of gate 44. This, of course, disables gate 44. As
long as the positive signal is being delivered to the signal
generator circuit 42a, the oscillator is energized and delivers an
output signal 60 via lead 58 and input line 27 to amplifier 28. The
amplified output 29 of course is delivered to the loudspeaker 30
for translation into an audible organ tone signal corresponding in
pitch to that secured by keying string VI at the first position. It
will be evident that for gate 44a to be enabled, string VI must
continuously contact plate 49 and segment 41a and that any
discontinuity in the string contact with either the plate 49 or
fret segment 41a will close the gate 44a and de-activate the
generator circuit 42a.
When string VI is keyed in the eighth position, the string assumes
the position generally illustrated at 63 and comes into electrical
contact with fret segments 41g and 41h. Contact with segment 41h
establishes a negative potential condition at the b input position
of "nor" gate 44h while the string contact with segment 41g
establishes a negative potential condition at the a input position
of gate 44h. By virtue of the readied condition provided by circuit
50 at the c input of gate 44h, the gate opens and delivers a
positive output signal 45h via diode 46h of the actuating circuit
43h to the tone signal generator circuit 42h associated with the
eighth keying position. When gate 44h opens, the positive output
signal is also delivered to the b input terminal of gate 51g. This
opens the gate and delivers a disabling positive signal to the c
input terminal of gate 44g and this disables circuit 43g. The
positive signal is also fed to the a terminal of gate 51f so that
all the "or" gates associated with the open string tone and the
string keying positions lower than the eighth position are opened
and deliver circuit disabling positive signals to the c positions
of the "nor" gates associated with the open and lower keyed string
tones. As a result, the actuating circuits associated with the
lower tones playable on the string are disabled.
The output signal 64 from generator 42a during the period when
string VI is in contact with both of the segments 41g and 41h is
fed via lead 58 and input lead 27 to amplifier 28 and the amplified
output 29 is translated into an audible musical tone in loudspeaker
30.
The conditioning circuits for strings I through V of guitar 11 are
designated at 100, 101, 102, 103 and 104 in FIG. 1 and the "or"
gates associated with the open string tones of these circuits are
designated at 94, 95, 96, 97 and 98 respectively. The actuating
circuits associated with the open string tones of strings I through
V inclusive are designated at 105, 106, 107, 108 and 109
respectively and from the foregoing description it will be evident
that when any of the strings of the guitar are keyed against the
keyboard a disabling positive output signal is impressed upon the c
input terminal of the actuating circuit associated with the open
string tone of the string. With this in mind, reference is now made
to FIG. 3 and wherein the embodiment illustrated in FIGS. 1 and 2
is shown as modified to avoid the need for sensing the open string
tones of the guitar 11 in order to actuate the organ 12 oscillators
associated with the open string tones when chords are being played
on the stringed instrument.
In the embodiment illustrated in FIG. 3 the control system is the
same both in components and operation as that illustrated in the
previous embodiment except that the actuating circuits associated
with the open string tones of the stringed instrument are modified
and controlled by an auxiliary circuit 70 that is designed to
respond to the simultaneous keying of any three of the strings I
through VI of the guitar and to enable the actuating circuits
associated with the open string tones of the unkeyed strings. Most
chords playable on the guitar require that at least three strings
be keyed, and hence the circuit 70 is designed to respond when
three or more strings are keyed to actuate the tone producers
associated with the open tones of the unkeyed strings.
Circuit 70 includes two input position positive "or" gates 71, 72,
73, 74, 75 and 76, three input position positive "nand" gates, 77,
78, 79 and 80, a four input position positive "nand" gate 81,
inverters 82, 83, 84, 85, 86 and 87, and single pole, single throw
switches designated at 88, 89, 90, 91, 92 and 93. The positive
"nand" gates open when all inputs are positive and provide a
negative output signal to gate 81. Gate 81 provides a positive
output signal when any input is a negative signal as will be
apparent to those skilled in the art.
The "or" gates associated with the open string tone actuating
circuits for strings I through V of guitar 11 are designated at 94,
95, 96, 97 and 98 in FIG. 3, and the conditioning circuits of the
control circuits 31, 32, 33, 34 and 35 are designated at 100, 101,
102, 103 and 104 respectively. The actuating circuits associated
with the open string tones playable on strings I through V
inclusive are designated at 105, 106, 107, 108 and 109 respectively
while the "nor" gates of these actuating circuits are designated at
105a, 106a, 107a, 108a and 109a.
In the illustration, the output signal of "or" gate 94 is tapped by
lead 112 of circuit 70 and delivered to the a position of gate 77.
By a lead 113 tapped into line 112, the signal is also delivered to
the a position of gate 71. The output signal of "or" gate 95 is
tapped by lead 114 of circuit 70 and delivered to the b position of
ate 77. By a lead 115 tapped to line 114, the signal is also
delivered to the b position of gate 71. The output signal of gate
96 is tapped by lead 116 and delivered to the a position of gate
78. By a lead 117 tapped in line 116, the signal is also delivered
to the a position of gate 72 as seen in the drawing. The output of
"or" gate 97 is tapped by line 118 and delivered to the b position
of gate 78 and by another lead 119 tapped in line 118 is also
delivered to the b position of gate 72. The output of "or" gate 98
is tapped by line 120 and delivered to the a position of gate 79.
By virtue of another line tap, the signal is also delivered by lead
121 to the a position of gate 73. Insofar as the circuitry
associated with the sixth string is concerned, the output of "or"
gate 51 is tapped by lead 122 of circuit 70 and delivered to the b
position of gate 79 and also to the b position of gate 73 by lead
123 tapped in line 122.
The output terminal of gate 71 is connected by lead 124 to the a
terminal of gate 80 and the output signal of gate 71 is also
delivered to the a input terminal of gates 75 and 76 as by leads
125 and 126 which are tapped into line 124. The output terminal of
gate 72 is connected by lead 127 to the b input terminal gate 80
and the signal from this gate 72 is also delivered to the b input
terminals of gates 74 and 76 by leads 128 and 129. The output
terminal of gate 73 is connected to the c input terminal of gate 80
by lead 130 and the output signal of this gate is also delivered to
the a input terminal of gate 74 by lead 131. The output signal of
gate 73 is also delivered to the b input terminal of gate 75 by
means of a lead 132 that is tapped into line 131. The outputs of
gates 74, 75 and 76 are delivered to the c input terminals of gates
77, 78 and 79 respectively as by leads 133, 134 and 135.
As seen in the drawings, the output terminals of gates 77, 78, 79
and 80 are connected by leads 136, 137, 138 and 139 to the input
terminals of gate 81. The output of gate 81 is delivered to trunk
lead 136a in circuit 70 and then delivered by leads 137a, 138a,
139a, 140, 141 and 142 to the inverters 82 through 87
respectively.
The output signals of inverters 82 through 87 are delivered by
leads 143, 144, 145, 146, 147 and 148 respectively to the b input
terminals of the "nor" gates respectively associated with actuating
circuits 105, 106, 107, 108, 109 and 43, and also to the a input
terminals of the gates 105a, 106a, 107a, 108a, 109a and 44 by
virtue of tie-in leads designated at 149, 150, 151, 152, 153 and
154 in FIG. 3.
Switches 88 through 93 inclusive are connected in lines 143 through
148 respectively. Most chords that are played on the guitar involve
the strumming of all the six strings and hence under such
circumstances, all of the switches 88 through 93 are maintained in
the closed position. Occasions arise however when certain chord
sequences involve the strumming of less than all the strings and
under such circumstances the switch or switches associated with the
strings that are not normally strummed during the chord playing
sequence would naturally be opened by the player.
Operation of the embodiment shown in FIG. 3 will now be explained
under the assumption that switches 88 through 93 are in the closed
positions. Under such circumstances, once the strings I through VI
and conditioning circuits 100, 101, 102, 103, 104 and 50 are
energized, the actuating circuits 105, 106, 107, 109, 109 and 43
are conditioned to receive enabling signals. Under such
circumstances a negative potential condition is established at each
of the c input positions for "nor" gates 105, 106a, 107a, 108a,
109a and 44. Under these ready conditions all of the gates 71
through 81 inclusive are closed and the negative potential
condition existing at the inputs of inverters 82 through 87
establishes gate disabling positive potential conditions at the a
and b inputs of gates 105a, 106a, 107a, 108a, 109a and 44.
Assuming now under the readied condition strings II, IV and V are
depressed by a player of the stringed instrument to play a chord.
Under such circumstances, gates 95, 97 and 98 are opened and
impress a gate disabling positive potential at the c inputs of
gates 106a, 108a and 109a. The positive output signals from gates
95, 97 and 98 are also delivered to gates 71, 72 and 73 and which
opens these gates and delivers positive gate opening signals to
each of the "or" gates 74, 75 and 76 as well as to the "nand" gate
80. Gates 77, 78 and 79 remain disabled under these circumstances
but the opening of gate 80 delivers a gate opening negative signal
to gate 81 which impresses a positive voltage condition at the
inputs of each of the inverters 82 through 87 inclusive. In turn
and by virtue of leads 143 through 148 inclusive, negative
potential conditions are established at the a and b positions of
each of the "nor" gates 105a, 106a, 107a, 108a, 109a and 44. This
enables circuits 105, 107 and 43 and actuates the signal generators
associated with the open string tones of the unkeyed strings I, III
and VI, while the conditioning circuits 101, 103 and 104 associated
with the keyed strings II, IV and V, render the actuating circuits
associated with the open tones and lower keying positions disabled.
Tracing of the circuitry shown in FIG. 3 will show that gate 77
opens when strings I and II and any one of the strings III, IV, V
or VI are keyed against the keyboard. It will also show that gate
78 opens when strings III and IV and any one of the strings I, II,
V and VI are keyed against the keyboard while gate 79 opens when
strings V and VI and any one of the strings I, II, III or IV are
keyed against the keyboard. Gate 80 on the other hand opens when
simultaneously one string from each of the pairs of strings I and
II, strings III and IV and strings V and VI are keyed against the
keyboard.Accordingly, when any three strings are keyed
simultaneously, one of the four gates 77, 78, 79 and 80 opens to
deliver a gate opening signal to gate 81 which in turn results in
the enabling of the circuits associated with the unkeyed
strings.
From the foregoing description it will be apparent that when three
or more strings are keyed in the playing of a chord the actuating
circuits associated with the open tones and lower keying positions
are disabled and that circuit 70 responds to the condition and
delivers a circuit enabling signal to the actuating circuit
associated with the open string tone of the unkeyed strings.
While only certain preferred embodiments of this invention have
been shown and described by way of illustration, many modifications
will occur to those skilled in the art and it is, therefore,
desired that it be understood that it is intended herein to cover
all such modifications as fall within the true spirit and scope of
this invention.
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