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Claims  |
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What is claimed is:
1. A stringed instrument including an on-board tuner comprising:
a detector for sensing vibrations produced by said stringed instrument and
for generating an electrical pitch signal representative of a pitch of the
vibrations, said detector being mounted in a cavity of said stringed
instrument;
a tuner circuit including: storage means for storing a set of pitch
reference values representing frequencies of musical notes; comparison
means for comparing the pitch signal to the pitch reference values to
determine which of the pitch reference values is a closest pitch reference
value and to determine a pitch deviation representing a difference in
frequency between the pitch signal and the closest pitch reference value;
and display control means for generating tuner circuit output signals
indicative of the pitch of the vibrations relative to the closest pitch
reference value, said tuner circuit being disposed in a cavity of said
stringed instrument;
a display for indicating a degree to which the pitch of the vibrations
deviates from the closest pitch reference value, said display receiving
the tuner circuit output signals and including: a string reader portion
having a series of light emitting elements corresponding to musical notes,
wherein one of the light emitting elements is illuminated in response to
the tuner circuit output signals to indicate the closest pitch reference
value; and a tune indicator portion indicating the degree to which the
pitch of the vibrations deviates from the closest pitch reference value,
said display being mounted on said stringed instrument such that said
display is readable by a musician holding said stringed instrument in a
normal playing position; and
an on-board power source for providing power to said tuner.
2. A stringed instrument according to claim 1, wherein the tune indicator
portion of said display comprises:
at least a first light emitting element being illuminated to indicate that
the pitch of the vibrations is substantially in tune with the closest
pitch reference value;
a second light emitting element being illuminated to indicate that the
pitch of the vibrations is flat relative to the closest pitch reference
value, such that the second light emitting element blinks at a rate
indicative of a degree to which the pitch of the vibrations is flat; and
a third light emitting element being illuminated to indicate that the pitch
of the vibrations is sharp relative to the closest pitch reference value,
such that the third light emitting element blinks at a rate indicative of
a degree to which the pitch of the vibrations is sharp.
3. A stringed instrument according to claim 1, further comprising: a body;
a neck extending from said body in a longitudinal direction and having a
front surface and a top surface lying substantially orthogonal to the
front surface; and
a volume control for controlling electrical amplification of said stringed
instrument, and wherein
said detector is a pickup which sends the pitch signal to the volume
control, and
said display is inlaid in the top surface of said neck such that said
display is substantially flush with the top surface of said neck.
4. A stringed instrument according to claim 3, wherein the tune indicator
portion of said display comprises:
at least a first light emitting element being illuminated to indicate that
the pitch of the vibrations is substantially in tune with the closest
pitch reference value;
a second light emitting element being illuminated to indicate that the
pitch of the vibrations is flat relative to the closest pitch reference
value, such that the second light emitting element blinks at a rate
indicative of a degree to which the pitch of the vibrations is flat; and
a third light emitting element being illuminated to indicate that the pitch
of the vibrations is sharp relative to the closest pitch reference value,
such that the third light emitting element blinks at a rate indicative of
a degree to which the pitch of the vibrations is sharp.
5. A stringed instrument according to claim 3, wherein the tune indicator
portion of said display comprises:
at least one in-tune light emitting element being illuminated to indicate
that the pitch of the vibrations is substantially in tune with the closest
pitch reference value;
a first series of light emitting elements located on one side of said
in-tune light emitting element, wherein light emitting elements of the
first series which are successively further displaced from the in-tune
light emitting element are illuminated to indicate a successively greater
degree of flatness of the pitch of the vibrations relative to the closest
pitch reference value; and
a second series of light emitting elements located on another side of said
in-tune light emitting element, wherein light emitting elements of the
second series which are successively further displaced from the in-tune
light emitting element are illuminated to indicate a successively greater
degree of sharpness of the pitch of the vibrations relative to the closest
pitch reference value.
6. A stringed instrument according to claim 3, wherein said tuner circuit
receives the pitch signal from said volume control only when said volume
control is adjusted to a minimum volume setting.
7. A stringed instrument according to claim 3, further comprising a tuner
on/off switch, wherein said pickup sends the pitch signal to the tuner
circuit directly and said power source is activated by said tuner on/off
switch such that said tuner circuit operates independently from said
volume control.
8. A stringed instrument according to claim 1, wherein said display is no
more than one inch in length.
9. A stringed instrument according to claim 1, wherein:
said stringed instrument is an acoustic stringed instrument having a body
with a sound hole;
said detector is a microphone located within the body of said stringed
instrument such that said microphone is substantially shielded from sound
interference from external sources; and
said display is mounted within the body of said stringed instrument such
that said display is visible through the sound hole.
10. A stringed instrument according to claim 9, further comprising a three
way switch, wherein:
a first setting of said switch deactivates said power source;
a second setting of said switch activates said microphone such that the
pitch signal is provided to the tuner circuit; and
a third setting of said switch activates said microphone such that the
pitch signal is provided to an output jack for external amplification.
11. A stringed instrument according to claim 1, further comprising:
a body having opposite near and distal ends, an upper portion, a lower
portion and a thickness; and
a neck having a substantially planar front surface defining a front face
plane and a top surface lying substantially orthogonal to the planar front
surface, said neck extending from the near end of said body in a
longitudinal direction, such that the upper portion of said body lies
above said neck and the lower portion of said body lies below said neck,
wherein:
the near and distal ends of said body curve out of said plane;
the upper and lower portions of said body curve out of said plane; and
the thickness of said body decreases from a bottom of the lower portion to
a top of the upper portion, and wherein
said display is inlaid in the top surface of said neck adjacent to the near
end of said body.
12. A stringed instrument according to claim 11, further comprising:
a strap assembly for a musical instrument, including:
a flat metal base plate attached to a rear face of said body of said
instrument at a balance point thereof;
a ring connector mounted to said base plate and having an integral hot
terminal extending through said base plate to said body of said
instrument, said ring connector being electrically insulated from said
base plate;
a male pivot arm having a body formed of a molded electrically insulative
material and having opposite inboard and outboard ends, said male pivot
arm being rotatably attached to said base plate at the inboard end, said
male pivot arm including: locks tabs located at the outboard end for
providing a mechanical connection; a male output connector located at the
outboard end for providing an electrical connection; electrical contacts
which form an electrical connection with the hot terminal of said ring
connector and with said base plate serving as ground; and an electrically
shielded cable connected on one end to the male output connector and on
another end to the electrical contacts;
a female pivot arm having a body formed of a molded electrically insulative
material and having opposite first and second ends, said female pivot arm
including: a housing located on the first end for receiving the lock tabs
of said male pivot arm; and a female receiving connector located within
the housing for receiving the male output connector, wherein said male and
female pivots arms are locked in a fixed position and an electrical
connection is formed between the male output connector and the female
receiving connector when the lock tabs of said male pivot arm are inserted
into the housing of said female pivot arm, and wherein said male pivot arm
and said instrument are mechanically and electrically disconnected from
said female pivot arm when the lock tabs are released from the housing of
said female pivot arm;
a padded section for resting on a musician's shoulder;
a first strap section connected on one end to the second end of said female
pivot arm and on another end to said padded section;
a second strap section having on one end a quick release clip housing and
being connected on another end to said padded section;
a quick release clip being attached to the first end of said female pivot
arm and having lock tabs which, when inserted into the quick release clip
housing, secure said strap assembly to a musician's body, and, when
released from the quick release clip housing, allow a musician to remove
said strap assembly along with said instrument; and
an output cable terminating on one end with the female receiving connector
and terminating on another end with an output jack.
13. A tuner for tuning a stringed instrument, comprising:
a detector for sensing vibrations produced by said stringed instrument and
for generating an electrical pitch signal representative of a pitch of the
vibrations, said detector being mounted in a cavity of said stringed
instrument;
a tuner circuit including: storage means for storing a set of pitch
reference values representing frequencies of musical notes; comparison
means for comparing the pitch signal to the pitch reference values to
determine which of the pitch reference values is a closest pitch reference
value and to determine a pitch deviation representing a difference in
frequency between the pitch signal and the closest pitch reference value;
and display control means for generating tuner circuit output signals
indicative of the pitch of the vibrations relative to the closest pitch
reference value, said tuner circuit being disposed in a cavity of said
stringed instrument;
a display for indicating a degree to which the pitch of the vibrations
deviates from the closest pitch reference value, said display receiving
the tuner circuit output signals and including: a string reader portion
having a series of light emitting elements corresponding to musical notes,
wherein one of the light emitting elements is illuminated in response to
the tuner circuit output signals to indicate the closest pitch reference
value; and a tune indicator portion indicating the degree to which the
pitch of the vibrations deviates from the closest pitch reference value,
said display being mounted on said stringed instrument such that said
display is readable by a musician holding said stringed instrument in a
normal playing position; and
a power source for providing power to said tuner.
14. A tuner according to claim 13, wherein the tune indicator portion of
said display comprises:
at least a first light emitting element being illuminated to indicate that
the pitch of the vibrations is substantially in tune with the closest
pitch reference value;
a second light emitting element being illuminated to indicate that the
pitch of the vibrations is flat relative to the closest pitch reference
value, such that the second light emitting element blinks at a rate
indicative of a degree to which the pitch of the vibrations is flat; and
a third light emitting element being illuminated to indicate that the pitch
of the vibrations is sharp relative to the closest pitch reference value,
such that the third light emitting element blinks at a rate indicative of
a degree to which the pitch of the vibrations is sharp.
15. A tuner according to claim 13, wherein:
said stringed instrument includes a neck having a top surface; and
said display is inlaid in the top surface of the neck such that said
display is substantially flush with the top surface of the neck.
16. A tuner according to claim 15, wherein the tune indicator portion of
said display comprises:
at least a first light emitting element being illuminated to indicate that
the pitch of the vibrations is substantially in tune with the closest
pitch reference value;
a second light emitting element being illuminated to indicate that the
pitch of the vibrations is flat relative to the closest pitch reference
value, such that the second light emitting element blinks at a rate
indicative of a degree to which the pitch of the vibrations is flat; and
a third light emitting element being illuminated to indicate that the pitch
of the vibrations is sharp relative to the closest pitch reference value,
such that the third light emitting element blinks at a rate indicative of
a degree to which the pitch of the vibrations is sharp.
17. A tuner according to claim 15, wherein the tune indicator portion of
said display comprises:
at least one in-tune light emitting element being illuminated to indicate
that the pitch of the vibrations is substantially in tune with the closest
pitch reference value;
a first series of light emitting elements located on one side of said
in-tune light emitting element, wherein light emitting elements of the
first series which are successively further displaced from the in-tune
light emitting element are illuminated to indicate a successively greater
degree of flatness of the pitch of the vibrations relative to the closest
pitch reference value; and
a second series of light emitting elements located on another side of said
in-tune light emitting element, wherein light emitting elements of the
second series which are successively further displaced from the in-tune
light emitting element are illuminated to indicate a successively greater
degree of sharpness of the pitch of the vibrations relative to the closest
pitch reference value.
18. A tuner according to claim 13, wherein said display is no more than one
inch in length.
19. A tuner according to claim 13, wherein:
said stringed instrument is an acoustic stringed instrument having a body
with a sound hole;
said detector is a microphone located within the body of said stringed
instrument such that said microphone is substantially shielded from sound
interference from external sources; and
said display is mounted within the body of said stringed instrument such
that said display is visible through the sound hole.
20. A tuner according to claim 19, further comprising a three way switch,
wherein:
a first setting of said switch deactivates said power source;
a second setting of said switch activates said microphone such that the
pitch signal is provided to the tuner circuit; and
a third setting of said switch activates said microphone such that the
pitch signal is provided to an output jack for external amplification. |
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Claims |
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Description |
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FIELD OF INVENTION
This invention relates to a stringed instrument having an on-board tuner
which allows a musician to tune the instrument rapidly during a musical
performance without diverting attention to any external devices.
Another aspect of the invention relates to an improved strap assembly which
permits the musician to remove one instrument and attach another
instrument without having to remove the strap assembly or disconnect a
separate connector cable. The strap assembly works in conjunction with an
ergonomic instrument body shape which conforms to the musician's body,
thereby minimizing torque on the musician's neck and shoulders.
BACKGROUND OF THE INVENTION
A commonly known problem related to stringed instruments is their natural
tendency not to stay in tune. Temperature fluctuations are one major cause
of this problem. As the ambient temperature increases, the pitch of
instrument strings tends to become sharp, and conversely, as the
temperature decreases, the pitch of instrument strings tends to become
flat. As a result, musicians are required to re-tune their stringed
instruments frequently. This problem is particularly acute for performing
musicians, because the ambient temperature tends to increase rapidly
during performances due to stage lighting. With conventional tuners, the
performing musician's opportunities to tune an instrument during a
performance are severely limited, since the attendant tuning process is
cumbersome. For instance, with electric stringed instruments, the musician
must divert attention away from the instrument and the audience in order
to focus on a remotely located tuner which is connected to the instrument
via an output cable. In the case of an acoustic stringed instrument, an
additional difficulty exists; external noise contends with the sound from
the string being tuned and interferes with the tuner properly discerning
the string's pitch. As a result, it is generally practical for a
performing musician to tune only before a performance or during breaks
between sets, often resulting in unacceptably poor tuning during
performance.
Attempts have been made in the art to provide stringed instruments with
on-board or built-in tuners. However, no existing tuner has satisfactorily
provided a convenient system that minimizes the time and effort required
by a performing musician to tune a stringed instrument during the course
of a performance.
International Application No. PCT/US89/02923 (Weise) discloses an
integrated guitar tuning system, wherein a tuning circuit is built into a
guitar, and a display comprising a pair of light emitting diodes (LEDs) is
mounted on the surface of the guitar body. One LED is illuminated to
indicate that the string being tuned is sharp, and the other LED is
illuminated to indicate the string being tuned is flat. However, the
display does not indicate which string is being tuned and does not
indicate the degree to which the string is out of tune. In addition, the
display is oriented outward from the front face of the guitar body such
that the LEDs are visible to anyone viewing the front of the guitar, such
as an audience.
International Application No. PCT/GB87/00302 (George) is directed to a
tuning aid located on the front face of a guitar body, which includes: a
dedicated pickup for sensing the pitch of the strings; and a row of LEDs
situated beneath the strings. Each LED corresponds to a string and is
illuminated when the corresponding string is played and in tune. Four
additional LEDs are used to indicate whether the played string is in tune.
One LED is illuminated when the pitch of the string is flat; a second LED
is illuminated when the pitch of the string is sharp; and the final two
LEDs are illuminated when the pitch of the string is in tune. The display
is readily visible to one viewing the front of the guitar, such as the
audience. However, the display is not conveniently located so as to be
easily viewed by the musician while holding the guitar in a normal playing
position. In addition, the sharp and flat LEDs do not indicate the extent
to which the pitch of a string deviates from the in-tune reference pitch.
US Pat. No. 4,899,636 (Chiba) relates to a tuning apparatus which mounts on
an external surface of an instrument via a suction cup and determines
pitch by sensing vibrations via a piezoelectric element. The apparatus
relies on vibrations being transmitted through the body of the instrument,
and therefore is not suitable for stringed instruments such as electric
guitars. The external mounting necessarily results in the tuning apparatus
protruding from the instrument, which may be aesthetically or functionally
undesirable to the musician. The display of the apparatus is an analog
meter which requires a relatively large display area. Further, in order to
properly attach to the instrument, the suction cup requires a
substantially plane surface area, which limits the selection of desirable
mounting locations.
Another problem encountered by performing musicians is the difficulty of
switching from one instrument to another instrument during a performance.
With an instrument having a conventional support strap and amplifier cord,
the musician must first unplug the amplifier cord, and then remove both
the instrument and strap by lifting the strap over the musician's head.
Next, the second instrument, together with its strap, must be placed over
the musician's shoulder, and the amplifier cord must be reattached. This
procedure is awkward and time consuming and can only be accomplished when
there is a significant amount of time between selections and rarely during
performance.
In addition, stringed instruments with conventional straps tend to impart
significant torque forces to the neck and shoulders of the musician,
which, over time, can result in chronic pain or discomfort. This torque is
caused by the inherent imbalance in the distribution of the weight of the
guitar on the musician's shoulders. This problem is especially troublesome
with instruments having a larger-than-conventional number of strings. For
example, a six string bass guitar requires a larger and heavier headstock
than a conventional four string bass guitar in order to accommodate the
additional strings. In order to counter balance the additional weight of
the headstock, the weight of the body of the guitar must be increased by
approximately three times the additional weight of the headstock. This
additional weight increases the torque forces experienced by the musician.
In addition, ease of mass-production dictates that most stringed
instruments have planar slab bodies. However, when the conventional
instrument is held in a normal playing position, the slab body shape
causes a significant amount of the instrument's mass to extend out from
the musician's body, thereby contributing to the torque experienced by the
musician through the strap assembly.
Finally, conventional stringed instruments, such as guitars, are shaped
such that musicians are forced to hold the guitar in a different playing
position while sitting than while standing. The lower portion of a
conventional guitar includes a lower horn. When a musician is sitting,
this lower horn rests against the musician's leg, thereby preventing the
musician from orienting the guitar at certain angles. If the musician
tends to practice while sitting and perform while standing, this
limitation on the guitar's angular orientation leads to inconsistent
playing conditions which may have an adverse affect on the quality of the
musician's performance.
SUMMARY OF THE INVENTION
It is therefore an objective of the present invention to provide a stringed
instrument having an on-board tuner for the purpose of easily and
conveniently tuning the instrument at any time without having to divert
attention away from the stringed instrument.
It is a further objective of the present invention is to provide an
on-board tuner which is compact and discreetly located on or within a
stringed instrument, yet is clearly visible and easily read by a musician
holding the stringed instrument in a normal playing position.
Another objective of the present invention is to provide an accurate visual
display indicating which string is being tuned and the degree to which the
pitch of the string varies from an in-tune reference pitch.
Another objective of the present invention is to provide the capability to
tune a stringed instrument to concert pitches without requiring
recalibration of tuner.
Another objective of the present invention is to provide a stringed
instrument having an on-board tuner which is integrated into the
instrument's existing electronics and takes advantage of the instrument's
existing control devices to activate and deactivate the tuner.
Another objective of the present invention is to provide a stringed
instrument having a strap assembly which allows the musician to remove and
attach different instruments rapidly without having to remove the strap
assembly or to remove or attach a separate output cable.
Another objective of the present invention is to provide a light-weight
ergonomic stringed instrument and strap assembly which minimize the torque
forces experienced by the musician.
Another objective of the present invention is to provide a stringed
instrument having a body which is contoured to minimize torque forces
experienced by the musician and to provide a connection for the strap
assembly.
Another objective of the present invention is to provide a stringed
instrument having a light-weight contoured body and strap assembly such
that the musician can hold the instrument in the same playing position
whether sitting or standing.
In order to achieve these objectives, a stringed instrument is provided
with an on-board tuner which is completely contained within the
instrument. According to one feature of the present invention, the tuner
detects vibrations of the strings through the existing pickup and
determines which string is being played and the deviation of the string's
pitch relative to an in-tune reference pitch. A tuner circuit employs a
quartz crystal to accurately compare the string's pitch to in-tune
reference pitches which are digital stored and never require
recalibration. The tuner display is compact and situated such that it is
not readily visible to casual observers such as an audience, yet is
oriented such that the musician can easily and conveniently view the tuner
display from a normal playing position. The tuner display thereby enables
the musician to quickly tune the instrument from a playing position
without requiring the musician to focus on anything other than the
instrument.
In a first embodiment, an electric stringed instrument, such as an electric
guitar, is provided with a tuner circuit which can be activated, for
instance, by turning the instrument's volume control to the minimum
setting. The tuner circuit receives signals from the instrument's pickup
and compares the signal's pitch information to a stored reference pitch.
The tuner circuit drives a display which is in-laid in the top surface of
the neck of the instrument near the instrument's body. The display is
flush with the instrument's surface and comprises a series of light
emitting elements. A string reader portion of the display indicates which
string is being played, and a tune indicator portion indicates the degree
of error (sharp or flat) between the string's pitch and the in-tune
reference pitch. Two centrally located in-tune light emitting elements are
illuminated to indicate that the string's pitch is in-tune. Light emitting
elements indicating that the string's pitch is sharp or flat are located
on opposite sides of the in-tune elements. The degree to which the
string's pitch is sharp or flat is indicated by the rate at which the
sharp and flat elements blink. Alternatively, rows of sharp and flat
elements can be located on opposite sides of the in-tune elements, such
that increasing pitch error is indicated by illuminating successively
further displaced elements.
In a second embodiment, an acoustic stringed instrument, such as an
acoustic guitar, is provided with a stand-alone tuner which is mounted
inside the instrument and is visible through the instrument's sound hole.
The tuner includes a condenser microphone which picks up the acoustic
vibrations of the strings and sends corresponding electrical signals to a
tuner circuit which is similar to that of the first embodiment. The
location of the tuner microphone within the instrument advantageously
prevents background interference from disrupting the tuning process by
shielding the microphone from external noise. The tuner is provided with a
three-way switch which allows the musician to activate the tuner or
provide the microphone output to an output jack for amplification. The
tuner display is located on the front face of the stand-alone tuner and
includes a string reader portion having a light emitting element for each
of the twelve notes in an octave and a tune indicator portion consisting
of three light emitting elements representing in-tune, sharp and flat. The
degree to which the string's pitch is sharp or flat is indicated by the
rate at which the sharp and flat LEDs blink.
In another aspect of the present invention, the stringed instrument is
provided with a strap assembly which attaches to a balanced pivot point on
the instrument and provides a single connection which serves as both an
electrical connection to the amplifier and a mechanical connection to the
strap assembly. The strap assembly enables the musician to remove and
attach different instruments without removing the strap assembly or
removing and attaching a separate electrical connection. The strap
assembly advantageously minimizes the torque forces applied to the
musician's neck and shoulders by equally distributing the weight of the
instrument due to the balanced pivot point mounting.
In another aspect of the present invention, the stringed instrument is
contoured to follow the shape of the musician's body, thereby reducing the
effective moment arm of the body and minimizing the torque experienced by
the musician through the strap assembly. The instrument body curves out of
the plane of the neck towards the musician in both the longitudinal and
transverse directions, and the thickness of the body is gradually reduced
towards the upper portion of the body. The instrument shape also allows
the strap attachment point to be positioned such that the instrument is
balanced in three dimensions, and prevents the strap attachment from
protruding from the rear face of the instrument.
The lower portion of the instrument body is tapered to substantially
eliminate the lower horn portion, allowing the musician to play the
instrument in the same position regardless of whether the musician is
sitting or standing. The tapered shape further serves to reduce the weight
of the instrument, and consequently, reduces the torque experienced by the
musician.
These and other objectives and features of the present invention will be
apparent from the following detailed description of the preferred
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a stringed instrument having an
on-board tuner and body contour according to a first embodiment of the
present invention.
FIG. 2 is a plan view of the lower back face of the stringed instrument
with a cut-away showing the instrument control cavity.
FIG. 3 is a block diagram of the tuner of the present invention.
FIG. 4 is a schematic diagram of a ganged volume pot circuit.
FIG. 5 is a block diagram of the tuner of the present invention showing an
alternate scheme for activating the tuner.
FIG. 6 is a circuit diagram of the tuner circuit of the present invention.
FIG. 7a is a perspective view of the tuner display according to the first
embodiment of the present invention.
FIG. 7b is a perspective view of an alternate tuner display according to
the first embodiment of the present invention.
FIG. 8 shows an angular view of the front face of an acoustic instrument
looking into the sound hole from beyond the top portion of the instrument,
whereby the display of a tuner according to a second embodiment of the
present invention can be seen.
FIG. 9a is a perspective view showing the tuner for an acoustic string
instrument of the second embodiment of the present invention.
FIG. 9b is a cut-away view of the back of the tuner of the second
embodiment showing the contents within the shell cavity.
FIG. 10 illustrates how the tuner of the second embodiment is attached to
the stringed instrument.
FIG. 11 is a perspective view of the strap assembly of the present
invention.
FIG. 12 is a close-up view of the components of the strap assembly.
FIG. 13a is a schematic diagram of the electrical connectors of the strap
assembly.
FIG. 13b is a circuit diagram of the electrical connectors of the strap
assembly.
FIG. 14 is a top view of the instrument showing the three dimensional shape
of the instrument's body along a longitudinal x-axis.
FIG. 15 is a side view of the instrument showing the three dimensional
shape of the instrument's body along a transverse y-axis.
FIGS. 16A and 16B are graphs showing the force and pressure caused by a
conventional strap and the force and pressure caused by the strap assembly
of U.S. Pat. No. 4,715,259, respectively.
FIG. 17 is a table showing the results of a study comparing the muscle
activity resulting from use of the '259 strap assembly to the muscle
activity resulting from use of a conventional strap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in detail using some specific
embodiments with reference to the accompanying drawings. In the context of
the present invention, a stringed instrument is any instrument which uses
strings to produce musical notes, including rhythm instruments such as
guitars and string instruments conventionally used in orchestras.
Referring to FIG. 1, an electric stringed instrument 1 is provided with a
tuner according to a first embodiment of the present invention. The
electric stringed instrument 1 can be any conventional electric guitar or
bass guitar or variation thereof having a neck 2, a body 3, and a set of
strings 4 which vibrate to produce musical notes of different pitch. The
body has a front face 5, a rear face 6 and an upper horn portion 7. The
instrument 1 is provided with at least one conventional pickup 8 which
lies beneath the strings 4 between the end of the fingerboard 15 and the
bridge 16. The pickup 8 senses the vibrations from the strings 4 and
generates electrical pitch signals representative of the pitch of the
vibrations.
As illustrated in FIG. 2, a control cavity 13 is cut into the lower portion
of the back face 6 of the body 3. Contained within the control cavity 13
is active and passive electronic control circuitry 14 for receiving and
processing the electrical signals generated by the pickup 8. The control
circuitry 14 includes volume control circuitry which will be described
below in conjunction with the tuner of the present invention. The volume
control circuitry generates an output volume signal which is sent to an
external amplifier and speakers (not shown).
Referring again to FIG. 1, a volume control knob 10 is located on the front
face 5 of the guitar body 3. The volume control knob 10 is connected to
the volume control circuitry and allows the musician to adjust the
amplitude of the output volume signal.
The tuner includes a tuner circuit 17 and an independent power source 18,
such as a battery. The tuner circuit 17 and power source 18 are preferably
located within the existing control cavity 13. Alternatively, if the
control cavity 13 does not have sufficient space, the tuner circuit 17 and
battery 18 can be located in a separate cavity located, for example,
between the end of the neck 2 and the pickup 8. In the case of a jazz
guitar (not shown) which typically has a large pick guard located on the
lower portion of the body, the tuner circuit can be mounted underneath the
pick guard.
The tuning apparatus also includes a display 20 inlaid into the top surface
of the neck 2 near the body 3. Alternatively, the display 20 could be
located on the upper horn portion 7 of the body 3. The display 20 consists
of a series of light emitting elements such as LEDs. The LEDs are oriented
upwards such that they are clearly visible to the musician while the
instrument 1 is being held in a playing position. The display 20 is
connected to the tuner circuit 17 via an interconnect cable 11 which is
routed though the body 3 of the instrument 1. The control and operation of
the display 20 will be described in greater detail hereinbelow.
Turning next to the tuner block diagram of FIG. 3, the electrical pitch
signal from pickup 8 is sent to a special ganged volume pot circuit 30. As
shown in FIG. 4, the ganged volume pot circuit 30 consists of a common
shaft 40 carrying two 250 k.OMEGA. volume pots 41 and 42. The shaft 40 is
connected to the volume control knob 10, and rotates as the volume control
knob 10 is turned by the musician. When the volume control knob 10 is
turned up, the ground to the tuner circuit 17 is disconnected, thereby
disabling the tuner, and the pickup signal is passed only to the volume
control circuitry. The tuner uses a positive ground system so that the
tuner circuit ground corresponds to the positive battery voltage. Because
the tuner circuit 17 is disconnected by the ganged volume pot circuit 40,
the tuner circuit 17 does not cause any additional loading on the system
which could impact sound quality.
Conversely, when the volume control knob 10 is turned to the minimum
setting, the pickup signal is passed to the tuner circuit 17 and the
volume control circuitry is shorted to ground. As a result, the tuner is
only operational when the instrument's volume signals are not being
amplified. The tuner circuit 17 is powered by a power source 18 which can
be, for instance, a 9 volt battery.
The block diagram of FIG. 5 illustrates an alternate scheme for activating
the tuner. The tuner circuit 17 is wired before the volume pot circuit 31.
As a result, the tuner will always receive the pickup signal, regardless
of the instrument's volume output. Instead of being activated by the
volume control knob 10, the tuner is activated by an on/off switch 12
located near the volume control knob 10 on the front face 5 of the
instrument 1 (see FIG. 1). The tuner circuit 17 is designed with a very
high input impedance to prevent any significant loading of the
instrument's circuitry and volume output, resulting in a negligible impact
on sound. If the musician desires to tune the instrument between songs,
the volume to the amplifier can be turned down via the volume control knob
10 so that no soun | | |
