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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic musical instrument having
the style of a woodwind musical instrument and being played in the manner
similar to that of playing a woodwind musical instrument.
2. Description of the Prior Art
Among electronic musical instruments, the most popular ones are keyboard
type electronic musical instruments, and recently developed and put into
practical use are woodwind-styled electronic musical instruments which
exhibit shapes similar to acoustic woodwind musical instruments and are
played in a similar manner, and are suitable for producing musical tones
which are very much like the tones of the acoustic wind instruments. Such
a woodwind-styled electronic musical instrument typically comprises an
instrument body of a generally rod-like shape provided with a plurality of
note designating keys arranged on the front surface thereof and a
mouthpiece incorporating a wind sensor for detecting the breath pressure
applied into the mouthpiece and a lip sensor for detecting the bite degree
(condition) applied onto the mouthpiece.
Among conventional woodwind-styled electronic musical instrument, such a
type of instruments have been known that comprises a seven-segment
indicator device for numerically indicating the detected value of the wind
sensor or the lip sensor. The numerical indication by the indicator is
useful for adjusting the threshold strength of the breath pressure to be
detected by the wind sensor for the instrument to produce a musical sound
when the breath pressure is above the threshold strength, or for adjusting
the neutral (standard) level of the bite strength to be detected by the
lip sensor for the control of produced sounds. The instrument player sees
the indicated values and adjust his/her manipulation of the instrument.
But the trouble may be such that the player does not readily understand
the meaning of the values. For example, in the case of the control pattern
of "tight lip" (to be explained hereinafter with reference to the
Figures), the performance is conducted by setting the neutral bite level
to be the bite condition of the lip sensor where the lip sensor is bitten
(pressed) by the lip to a certain extent. But the above-mentioned
numerical indication will not be intuitively understandable to know the
neutral level of bite, and thus the adjustment of the player's bite
strength will not be facilitated greatly even with the indicator equipped.
SUMMARY OF THE INVENTION
It is, therefore, a primary object of the present invention to provide a
woodwind-styled electronic musical instrument comprising an instrument
body arranged with a plurality of note designating keys and a mouthpiece
arranged with a lip sensor for detecting the degree of lip bite so
improved that the bite condition of the lip sensor is readily and
intuitively understandable at a glance by the player during playing on the
instrument.
In order to accomplish the abovementioned and other objects, an electronic
musical instrument of a woodwind style in one aspect of the present
invention comprises an instrument body provided with a plurality of
manipulating note keys arranged thereon for generating note designating
information which designates musical notes to be played, a mouthpiece
arranged at the top end of the instrument body and provided with a bite
manipulator for receiving a bite condition of the player and generating
bite information, a bite indicator for indicating a bite condition of the
bite manipulator as operated by the instrument player, a musical tone
control signal generator for generating a signal which controls production
of a musical tone at least in accordance with the note designating
information and the bite information, and a bite indicator control device
which controls the bite indicator to exhibit a first indication state when
the bite manipulator is manipulated to or in the vicinity of a neutral
level which is a middle extent of the bite degree of the bite manipulator,
and to exhibit a second indication state when the bite manipulator is
manipulated to a level which is neither the neutral level nor the vicinity
thereof. The first indication state is preferably a state where the bite
indicator is not lit while the second indication state is preferably a
state where the bite indicator is lit. The control rate at which the
musical tone control signal controls production of a musical tone in
accordance with the bite information is selectable. With this arrangement,
the player can readily and intuitively recognize the neutral bite level
which is a bite degree of the middle extent and the vicinity of the
neutral bite level from the indication pattern of the indicator.
According to another aspect of the present invention, an electronic musical
instrument of a woodwind style comprises an instrument body provided with
a plurality of manipulating note keys arranged thereon for generating note
designating information which designates musical notes to be played, a
mouthpiece arranged at the top end of the instrument body and provided
with a bite manipulator for receiving a bite condition of the player and
generating bite information, a bite indicator for indicating a bite
condition of the bite manipulator as operated by the instrument player, a
musical tone control signal generator for generating a signal which
controls production of a musical tone at least in accordance with the note
designating information and the bite information, an indicator control
condition setting device capable of setting at least a first and a second
control condition, the first control condition being that the bite
information is to exhibit a neutral level when the bite manipulator is
manipulated to a middle extent of the bite degree and the second control
condition being that the bite information is to exhibit a neutral level
when the bite manipulator is manipulated to a substantially zero extent of
the bite degree, and a bite indicator control device which controls the
bite indicator to exhibit a first indication state when the bite
information exhibits the neutral level or the vicinity thereof, and to
exhibit a second indication state when the bite information exhibits
neither the neutral level nor the vicinity thereof. With this instrument,
the player can selectively use a first control mode in which the bite
information is outputted with the neutral bite level set at the middle
degree of bite strength or a second control mode in which the bite
information is outputted with the neutral bite level set at the non-bite
state, and can easily recognize at a glance the neutral bite level and its
vicinity from the indication pattern by the indicator.
According to further aspect of the present invention, an electronic musical
instrument of a woodwind style comprises an instrument body provided with
a plurality of manipulating note keys arranged thereon for generating note
designating information which designates musical notes to be played, a
mouthpiece arranged at the top end of the instrument body and provided
with a bite manipulator for receiving a bite condition of the player and
generating bite information, a bite indicator for indicating a bite
condition of the bite manipulator as operated by the instrument player, a
musical tone control signal generator for generating a signal which
controls production of a musical tone at least in accordance with the note
designating information and the bite information, and a bite indicator
control device which controls the bite indicator to exhibit a first
indication state when the bite manipulator is manipulated to or in the
vicinity of a neutral level which is a non-bite degree or substantially
zero extent of the bite degree of the bite manipulator, and to exhibit a
second indication state when the bite manipulator is manipulated to a
level which is neither the neutral level nor the vicinity thereof. The
musical tone control signal controls production of a musical tone in
accordance with the bite information at a selectable control rate.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, and to show how the
same may be practiced and will work, reference will now be made, by way of
example, to the accompanying drawings, in which:
FIGS. 1(a) and 1(b) are a front view and a side view showing a
configuration of an embodiment of an electronic musical instrument of a
woodwind style according to this invention;
FIG. 2 is a rear view showing a configuration of the same embodiment of
this invention;
FIG. 3 is a bottom view of the same embodiment of this invention;
FIG. 4 is an enlarged partial rear view of FIG. 2, showing octave
designating switches;
FIG. 5 is a block diagram showing an entire structure of the hardware of an
embodiment of an electronic musical instrument of a woodwind style
according to this invention;
FIG. 6 is a flowchart of a main routine of a tone production control
processing which is executed at the start of a tone production in an
embodiment of an electronic musical instrument of a woodwind style
according to this invention;
FIG. 7 is a flowchart of a main routine of a tone production control
processing which is executed during the continuance of a tone production;
FIG. 8 is a flowchart of a subroutine of a DIP switch set processing
executed at step S51 in FIG. 6;
FIG. 9 is a flowchart of a subroutine of a lip indication control
processing executed at step S54 in FIG. 6 and step S73 in FIG. 7;
FIG. 10 is a flowchart explaining the details of step S64 in FIG. 7 for
outputting breath pressure data in the MIDI format;
FIG. 11 is a graph showing controlling patterns of the lip sensor in an
embodiment of an electronic musical instrument of a woodwind style
according to this invention; and
FIG. 12 is a chart showing fingering patterns to be used in an embodiment
of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Illustrated in FIGS. 1 through 3 of the drawings show the external
appearance of an embodiment of an electronic musical instrument of a
woodwind style according to this invention, in which FIG. 1(a) is a front
view, FIG. 1(b) a right side view, FIG. 2 a rear view and FIG. 3 a bottom
view. FIG. 4 is an enlarged partial rear view around the octave
designating switches.
The embodiment of an electronic musical instrument of a woodwind style
according to this invention comprises, as illustrated in FIGS. 1(a) and
1(b), an instrument body 1, a mouthpiece 2, key switches 3 (including note
designating keys 3a-3p), a first LED 4, a second LED 5, a lip sensor 6, a
strap ring 7, a setup switch 8, a thumb rest 9, a pitch bend wheel 10 and
a cable clamp 11. The embodiment instrument further comprises, as shown in
FIG. 2, setting controls 12 (including 12a-12d), DIP switches 13, octave
designating key switches 14, a key hold switch 15, a program change switch
16, a power switch 17, a power jack 18, a MIDI output terminal 19, WX
output terminal 20 and a breath drain 21. The embodiment still further
comprises, as shown in FIG. 3, a key shaft 22 and a key rod 23. FIG. 4
shows a portion around the octave designating switches 14 in FIG. 2, and
illustrates a thumb rest 14a, octave shift-up switches 14b and 14c, and
octave shift-down switches 14d and 14e.
As shown in FIG. 1(a), the instrument body 1 of an electronic musical
instrument of this embodiment is of an elongated rod shape and is provided
with a plurality of key switches 3a-3p on the front surface thereof, and
the mouthpiece 2 is provided with the lip sensor 6 of which the reed
portion is depicted in FIGS. 1(b) and 2, and with a wind sensor (breath
sensor) inside thereof (although not depicted in these Figures). The lip
sensor 6 is to detect the bite condition (degree) at the reed area and the
wind sensor is to detect the breath pressure applied into the mouthpiece
2. The upper front portion of the instrument body 1 is configured in a
slope shape continuing to the front surface of the mouthpiece 2 as shown
in FIG. 1(b), and is provided with the #1-LED (light emitting diode) 4 and
the #2-LED 5. The player of the instrument can recognize the manipulating
conditions of the lip sensor 6 and the wind sensor by way of the lighting
or extinguishing state of these LED's 4 and 5.
There are, for example, two patterns of control manners with the lip
sensor. One is a tight lip control in which the performance is conducted
by continuously pressing the reed by the lip (i.e. lower lip) and the
sound production is controlled around the bite strength of a middle
degree, which is defined as a neutral bite level and outputs a neutral
(reference) value signal. The other is a loose lip control in which the
performance is conducted by occasionally pressing the reed by the lip and
the sound production is controlled by setting a neutral bite level at the
non-bite state (zero degree of bite).
In the tight lip control pattern, the manipulation information to be
outputted for the control of sound production is of such a characteristic
that the neutral position is set at a middle level of the bite strength
detected by the lip sensor. And in this pattern, the #1-LED 4 is in its
extinguished state when the detected bite level is at or in the vicinity
of the neutral position as defined by the middle bite strength whereas the
#1-LED 4 is in its lit state when the detected bite level is at any other
positions.
In the loose lip control pattern, the manipulation information to be
outputted for the control of sound production is of such a characteristic
that the neutral position is set at the zero level (non-bite state) of the
bite strength detected by the lip sensor. And in this pattern, the #1-LED
4 is in its extinguished state when the detected bite level is at or in
the vicinity of the neutral position as defined by the zero bite strength
(non-bite state), whereas the #1-LED 4 is in its lit state when the
detected bite level is at any other positions than the neutral region.
The #2-LED 5 is to indicate the manipulation condition of the wind sensor,
and therefore the #2-LED 5 is extinguished when the breath pressure does
not reach the basic strength necessary for the sound production control
and is lit when the breath pressure has reached (is at or above) the basic
strength necessary for the sound production control.
The explanation will be first made on the entire structure of the
woodwind-styled electronic musical instrument of this embodiment with
reference to FIGS. 1(a) through 5, and thereafter on the specific
operation of the indicators exhibiting the manipulation condition of the
lip sensor with reference to flowcharts in FIGS. 6 through 10.
In FIG. 1(a), among the note designating key switches 3 arranged on the
front surface of the instrument body 1, those referencemans 3a-3h are for
the left finger manipulation, being arranged nearer to the mouthpiece 2,
and those referenced as 3i-3p are for the right finger manipulation, being
arranged nearer to the tail end of the instrument body 1. On the rear
surface of the instrument body 1, near the central position on the
longitudinal center axis thereof, there is provided a thumb rest 9
protruding from the rear surface to be hooked by the right thumb for
supporting the body 1 and a pitch bend wheel near the thumb rest 9 but a
little bit deviated therefrom toward the tail end of the instrument and
toward left in the transverse direction, as shown in FIGS. 1(b) and 2. The
pitch bend wheel 10 is a rotary type variable resister with a spring bias
to return to the center position of control. The manipulating portion of
the pitch bend wheel 10 has an arcuate external surface with a recess
position at the center of the surface when the wheel is returned to the
center position by the bias spring. The wheel 10 is operated by the inside
surface of the right thumb and is moved back and forth along the direction
of the center axis of the instrument body 1. The pitch bend wheel 10
produces a real time control signal included in the tone production
control signal together with the MIDI signal to control the tones produced
by an external device including tone generators. Also on the rear surface
of the instrument body 1, there are provided a strap ring 7 to be coupled
with a hook on the strap belt which is hung around the neck of the player
and a cable clamp 11 to be connected with an external cable.
As shown in FIG. 2, there are provided various control manipulators on the
rear surface of the instrument body 1. A plurality of setting controls
12a-12d may be adjusting variable resistors for such as a wind gain
adjustment, a wind zero (basic wind intensity) adjustment, a lip gain
adjustment and a lip zero (neutral bite level) adjustment, and these
variable resistors are suitable for setting analog values. Also provided
here are DIP (dual in-line package) switches 13 for setting various on/off
conditions. The octave designating switches 14 of an on/off type are
arranged at the position where the left thumb abuts during performance as
shown in the enlarged partial rear view of FIG. 4, and are to be
manipulated by the left thumb to change the combination of the on/off
states of the switches. The operated conditions of the octave designating
switches 13 determine the octave shift amount of the musical note as
designated by the note designating switches 3a-3p.
The setup switch 8 is to be manipulated simultaneously or substantially
simultaneously with other control manipulators to set various functions.
For example, when the pitch bend wheel 10 is manipulated in association
with the setup switch, the instrument is set at an audition mode. The
audition mode is a mode in which the output from the pitch bend wheel is
handled as an breath pressure output and the tones will be produced under
the condition that the pitch bend wheel is actuated in place of the wind
sensor. Namely, in the audition mode, a trial (test) tone production will
be realized by manipulating the non-mouth manipulators such as the pitch
bend wheel 10 without operating the mouth manipulators such as the wind
sensor and the lip sensor 6. The simultaneous operation of the pitch bend
wheel with the octave designating switch 14 will set the wind gain of the
wind sensor. Further, the simultaneous operation with the note designating
key switches 3 will change the normal outputting channels for the MIDI
output in correspondence with the individual key switch depressed. Still
further, the pressure value of the wind sensor will be reset to "0" at the
moment the setup switch 8 is pressed.
The key hold switch 15 is to keep the played tone sounding continuously.
The program change switch 16 is for switching over (selecting) the tone
colors of the tone generator. Other than those manipulators, the power
switch 17, the power jack 18, MIDI output terminal 19 for outputting the
produced musical tone production control signals to an external device
such as a tone generator device, the WX output terminal 20 for connecting
the tone production control signals to a unique tone generator device and
simultaneously receiving a power supply therefrom, and a breath drain 21
for bypassing the breath (air) blown into the mouthpiece 2 and for
draining saliva or water.
Referring to FIG. 3 showing the bottom view of the instrument, the
construction of the note designating key switches 3 and the key sensor
will be described hereinbelow. The key switches 3a-3p are different in
shape from one another, but for the convenience sake a single key switch 3
for the illustrative purpose is depicted in FIG. 3. The key switch 3 is of
a generally L shape and is rotatably supported above the body 1 by a key
shaft 22 inserted through the bent portion of the L shape. A rod 23 is
formed by protruding from the front surface of the body 1. The key switch
3 is biased by a spring (not shown) so that the lower surface of the key
switch 3 will be normally kept off from the rod 23. When the player
depresses the key switch 3, the pressing portion of the key switch 3 will
abut the rod 23, and an actuator at the lower end of the rod 23 presses a
key sensor provided inside the body 1. The key sensor may be a pressure
sensitive sensor of an elastic sheet form of which the resistance value
varies in response to the applied pressure. The on/off manipulation
condition of the key switch 3 is detected by comparing a voltage at a
voltage divider circuit including the key sensor with a reference
threshold voltage. Further, the detected voltage value may be utilized to
detect the player's finger pressure applied on the key switch 3 so as to
realize an after-touch control or else as described later.
Referring to FIG. 4 showing the octave designating switch area in an
enlarged scale, an explanation will be made about the shapes and the
functions of the octave designating switches 14b-14e. In the case of the
illustrated embodiment, a thumb rest 14a is provided on the rear surface
of the instrument body 1 along the central axis of the body 1 for the
abutment with the left thumb. Adjacent to the thumb rest 14a in its
right-up direction are formed octave shift-up switches 14b and 14c close
to each other, the switch 14b being of a partly cut-off circle shape and
the switch 14c being approximately of a sector shape. Further adjacent to
the thumb rest 14a in its right-down direction are formed octave
shift-down switches 14d and 14e close to each other, the switch 14d being
of a partly cut-off circle shape and the switch 14e being approximately of
a sector shape. The shape of the thumb rest 14a is substantially of a
circle having a circumference which follows the inner side peripheries of
the octave shift-up switches 14b and 14c and of the octave shift-down
switches 14d and 14e. These switched are different in shape and position
from each other as seen from FIG. 4. The differences given are such that
the player can clearly identify which one he/she is touching according to
the shape and the position, when the thumb abutting the thumb rest 14a is
rotated thereon to successively touch any one of the octave designating
switches 14.
When none of the octave designating switches 14b-14e are manipulated, the
pitches of the tones produced are respectively those as will be described
later with reference to the fingering patterns in FIG. 12, i.e. no octave
shift is imparted to the designated standard note pitch. When the octave
shift-down switch 14d is actuated alone, the octave level of the produced
tone will be shifted downward by one octave. When the octave shift-down
switches 14d and 14e are both actuated, the octave level of the produced
tone will be shifted downward by two octaves. When the octave shift-down
switch 14e is actuated alone, the octave level of the produced tone will
be shifted downward by three octaves. Likewise in reverse way, when the
octave shift-up switch 14b is actuated alone, the octave level of the
produced tone will be shifted upward by one octave. When the octave
shift-up switches 14b and 14c are both actuated, the octave level of the
produced tone will be shifted upward by two octaves. When the octave
shift-up switch 14c is actuated alone, the octave level of the produced
tone will be shifted upward by three octaves. Namely, with the depressed
state given a value "1" and with the non-depressed state given a value
"0", the octave shift switch group including the switches 14b-14e outputs
seven levels of the signal value, i.e. -3 through +3. In this way, the
octave designating switch group 14 outputs different manipulation
information signals successively representing the amount of manipulation
on to the switch group 14 according to the movement of the left thumb.
FIG. 5 is a block diagram illustrating an entire hardware construction of
an embodiment of an electronic musical instrument according to this
invention. In this Figure, like reference numerals as in FIGS. 1(a), 1(b)
and 2 are given like reference numerals to dispense with duplicated
explanation. Connected with a bus line 31 are a CPU (central processing
unit) 38 having the function of logic operation, a ROM (read only memory)
37 storing various programs, a RAM (random access memory) 36 preparing
work areas to be used for the processing by the CPU 38. To the bus 31 are
connected various analog inputting manipulators via an A/D converter
section 32, such as key sensors 33, a wind sensor 34, the lip sensor 6,
the pitch bend wheel 10 and setting controls 12, where the A/D converter
section 32 scans the respective analog inputting manipulators to detect
the respective analog signals and convert them into digital value signals
before supplying to the bus 31. Switch type manipulators connected to the
bus 31 are the octave designating switches 14, the setup switch 8, and
other switches 35. The key sensor 33 is a pressure sensitive resister
exhibiting a resistance value responsive to the depression strength of the
key switch 3 as explained with reference to FIG. 3. For example, the key
sensor 33 is connected in series with a fixed resister to constitute a
voltage divider, to which is applied a predetermined voltage to output a
divided analog voltage, which in turn is inputted into the A/D converter
section 32. Output sections connected to the bus 31 are an LED driver
circuit 39 to control the #1 and #2 LED's 4 and 5, and an output interface
40 for outputting tone production control signals such as MIDI signals.
When the programs stored in the ROM 37 are executed by the CPU 38, the
associated signal processings take place to output the processed results
(tone production control signals) at the MIDI output terminal 19 and at
the WX output terminal 20 via an output interface 40. Then an external
tone generator and sound system receives the MIDI data signals and
produces musical tone waveforms and emits musical sounds. Prior to the
manipulation of the instrument for starting a musical performance, various
parameters may be set respectively by means of the setting controls 12
such as, for example, variable resisters 12.
When the player manipulates the key switches 3 arranged on the instrument
body 1 for designating notes for the performance, the key sensors detects
the pressing strengths onto the keys, and then the A/D converter section
32 outputs digitized pressure values and on/off states of the key switches
3. Also the manipulation conditions of the octave designating switches 14
and the setup switch 8 are detected and appear on the bus 31. The CPU 38
accesses these manipulators according to the program stored in the ROM 37
to receive the respective pieces of information and provides tone
production control signals based on those pieces of information for
outputting from the output interface 40 to the external tone generator.
FIGS. 6 through 10 are flowcharts describing the operation of an example of
the electronic musical instrument of a woodwind style according to this
invention. The flowcharts are primarily for the purpose of explaining how
the #1 and #2 LED's 4 and 5 function in the invention, and therefore the
details of the other processing steps are omitted where such would be
understandable for the readers in this technical field. Among these, FIG.
6 is a flowchart of the processing conducted at the start of a tone
production in the main routine of the tone production control, FIG. 7 is a
flowchart of the processing conducted during the continuance of a tone
production in the main routine of the tone production control, FIG. 8 is a
flowchart of a subroutine of a DIP switch set processing executed at step
S51 in FIG. 6, FIG. 9 is a flowchart of a subroutine of a lip indication
control processing executed at step S54 in FIG. 6 and step S73 in FIG. 7,
and FIG. 10 is a flowchart explaining the details of a specific example of
step S64 in FIG. 7 for outputting breath pressure data in the MIDI format.
In the normal performance mode of operation, the wind sensor 34 controls
the operation of tone production. When the player blows breath air into
the mouthpiece 2 for the performance and the wind sensor 34 is detecting
the breath pressure which is above a predetermined threshold, the
instrument outputs tone production control signals including MIDI signals
based on the output from the key switches and the output from the wind
sensor. While FIGS. 6 and 7 illustrate such an example where the tone
production depends on the wind sensor's detection level, an alternative
example may be such that the tone production control signals including
MIDI signals will be outputted based on the output from the lip sensor 6
and the output from the note key switches, when the lip sensor 6 is
detecting the bite strength which is above a predetermined threshold.
Referring to FIG. 6, upon turning on the power switch, the main routine
processing initiates. Then, after the regular initialization of the
various registers, a step S51 conducts the processing of the DIP switches
including the setting of control mode of the lip sensor 6, and then the
process moves forward to a step S52. The processing procedure of the step
S51 will be explained in more detail with reference to FIG. 8, which is a
subroutine flowchart of the step S51. At a step S81, the process is to
take in the respective conditions of the DIP switches 13. Steps S82
through S85 are to set a lip control pattern #1 which selectively sets
either of a normal type control and a wide type control by means of the
first switch among the DIP switches 13. Steps S86 through S89 are to set a
lip control pattern #2 which selectively sets either of a tight type
control and a loose type control by means of the second switch among the
DIP switches 13. A step S90 is a comprehensive expression of various
processes for setting various functions and various parameters by means of
#3 and further switches among the DIP switches 13, where the operations
will be understood by the reader through similar manners as described in
connection with #1 or #2 switch. In FIG. 8, the conditions of all the DIP
switches 3 are detected at the step S81, but individual condition of each
DIP switch 3 may be evaluated separately at the setting of each control
pattern (category). Although not shown in the flowcharts, the setting
controls (variable resisters) 12c and 12d may be for adjusting the lip
gain and the lip zero level, respectively, for example by preparing
conversion tables having a basic conversion pattern so that the setting
control 12c adjusts the lip zero level (neutral position) and the setting
control 12d adjusts the lip gain (conversion gain).
Now, an explanation will be made about the controlling patterns of the lip
sensor 6, referring to the graph in FIG. 11. The graph shows the relation
between the output from the lip sensor 6 and the controlling signal to be
used for the tone production. In the Figure, the abscissa is the A/D
converted value LP of the output from the lip sensor 6 to be inputted to
this conversion process, and the ordinate is the control output value TBL
(m,LP) to be outputted from this conversion as the control information.
The value of LP is zero (i.e. LP=0) when the lip sensor 6 is at its
natural state with no bite strength is applied thereto by the player. The
LP value is converted into a control output value according to one of the
four conversion tables (i.e. curves in the graph) respectively having
parameters m=1, 2, 3 and 4.
The conversion table of m=1 is of a control pattern of tight and normal
conditions. The neutral position (lip zero point) is defined at a
predetermined middle level of the bite strength applied onto the reed
element of the lip sensor 6. In the saturation region where the LP value
is zero and its vicinity, the control output value TBL (1,LP) exhibits a
negative value "-32". As the value LP increases, the control output value
TBL (1,LP) increases accordingly, and in the dead zone provided at the
neutral point and its vicinity, the control output value TBL (1,LP)
exhibits the neutral value "0". Further, as the value LP increases, the
control output value TBL (1,LP) increases again accordingly and reaches a
positive maximum value "+8" to saturate thereafter.
The conversion table of m=2 is of a control pattern of loose and normal
conditions. The neutral position (lip zero point) is defined at a non-bite
state of the reed of the lip sensor 6. In the dead zone where the LP value
is zero and its vicinity, the control output value TBL (2,LP) exhibits a
value "0". As the value LP increases, the control output value TBL (2,LP)
increases accordingly up to a positive maximum value "+32".
The conversion table of m=3 is of a control pattern of tight and wide
conditions. The neutral position (lip zero point) is defined at a
predetermined middle level of the bite strength applied onto the reed
element of the lip sensor 6. In the saturation region where the LP value
is zero and its vicinity, the control output value TBL (3,LP) exhibits a
negative value "-64". As the value LP increases, the control output value
TBL (3,LP) increases accordingly, and in the dead zone provided at the
neutral point and its vicinity, the control output value TBL (3,LP)
exhibits the neutral value "0". Further, as the value LP increases, the
control output value TBL (3,LP) increases again accordingly and reaches a
positive maximum value "+16" to saturate thereafter.
The conversion table of m=4 is of a control pattern of loose and wide
conditions. The neutral position (lip zero point) is defined at a non-bite
state of the reed of the lip sensor 6. In the dead zone where the LP value
is zero and its vicinity, the control output value TBL (4,LP) exhibits a
value "0". As the value LP increases, the control output value TBL (4,LP)
increases accordingly up to a positive maximum value "+64".
While four kinds of conversion tables are illustrated and explained
hereinabove in FIG. 11 for m=1 through 4, those are only for the purpose
of examples of this invention. Therefore, the width of the dead zones or
the saturation regions (as indicated by the arrows), the level of
TBL(m,LP) to exhibit in the direction of the ordinate at the dead zones,
the range LP covering from the non-bite condition up to the full
(strongest) bite condition may be differently provided by preparing
further conversion tables labeled with m=5 or more according to the
necessity.
Referring to the flowchart of FIG. 8 again, steps for the DIP switch set
processing subroutine (S51 in FIG. 6) will be explained in detail
hereunder. At the step S81, inputs from the DIP switches are loaded in the
work area for data processing. The step S82 is to judge whether there is
an on/off event at the switch #1, i.e. whether the switch condition has
been changed from the off state to the on state or from the on state to
the off state. When there is an on/off event, the process goes forward to
the step S83, and when there is not an on/off event the process moves
forward to the step S86. At the first execution of this step S82 after the
power switch has been turned on, the step S82 is to judge "yes". The step
S83 is to select a type of the lip control pattern of the lip sensor 6 to
be used for the tone production control according to the condition of the
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