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Claims  |
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We claim:
1. An automatic performance device with tempo follow-up function
comprising:
an operator element,
memory means for storing note-length information of corresponding musical
tones to be performed, each said note-length information representing a
reference timing which represents a timing to operate said operator
element,
read out means for sequentially reading out said note-length information
from said memory means in the order in which such corresponding musical
tones are to be performed,
control data forming means connected to said memory means and said read out
means for forming and outputting control data in response to the operation
of said operator element and said note-length information, said control
data having a value relating to the time difference between the timings of
said operator element operation and said reference timing,
automatic performance means for performing an automatic performance at a
certain tempo, and
tempo varying means for varying said certain tempo of said automatic
performance in accordance with said control data.
2. An automatic performance device with tempo follow-up function according
to claim 1 wherein:
said control data forming means comprises measuring means for measuring an
interval of operations of said operator element in accordance with said
note-length information, the value of said control data corresponding to
the value of said measured interval.
3. An automatic performance device with tempo follow-up function according
to claim 2 wherein said measuring means comprises:
pulse generating means for generating pulses having a frequency determined
by said note-length information, and
counting means for counting said pulses until said operator element
operation, said measured interval corresponding to the count value.
4. An automatic performance device with tempo follow-up function according
to claim 1 wherein said control data forming means comprises:
measuring means for measuring an interval of operations of said operator
element in accordance with said certain tempo, and
comparing means for comparing said interval with said reference timing
represented by said note-length information and for outputting said
control data, said control data being the result of the comparison.
5. An automatic performance device with tempo follow-up function according
to claim 4 wherein:
said tempo varying means comprises tempo pulse generator for generating
tempo pulses in accordance with said control data, said tempo pulses
having a frequency corresponding to the value of said control data so that
said certain tempo of said automatic performance is varied in response to
said tempo pulses.
6. An automatic performance device with tempo follow-up function according
to claim 5 wherein:
said measuring means comprises counter means for counting said tempo pulses
from previous operation to current operation of said operator element; and
said comparing means comprising subtracting means for performing a
subtracting operation of the count value and said note-length information,
the value of said control data corresponding to the result of the
subtraction.
7. An automatic performance device with tempo follow-up function according
to claim 1 wherein said control data forming means comprises:
reference timing designating means for designating said reference timing
based on said certain tempo and said note-length information, and
comparing means for comparing said reference timing and the timing of said
operator element operation and outputting said control data, said control
data being the result of the comparison.
8. An automatic performance device with tempo follow-up function according
to claim 7 wherein:
said tempo varying means comprises tempo pulse generator means for
generating tempo pulses in accordance with said control data, said tempo
pulses having a frequency corresponding to the value of said control data
so that said certain tempo of said automatic performance is varied in
response to said tempo pulses.
9. An automatic performance device with tempo follow-up function according
to claim 8 wherein:
said reference timing designating means comprises counting means for
counting said tempo pulses and for outputting a reference pulse when the
count value reaches to the value determined by said note-length
information, and
said comparing means comprises detecting means for detecting the time
difference between the output timing of said reference pulse and the
operation timing of said operator element.
10. An automatic performance device with tempo follow-up function according
to claim 7 wherein:
said memory means further stores note-name information corresponding to
said note-length information,
said read out means further reads out said note name information from said
memory means, and
said operator element comprises a key corresponding to each of said
note-name information, said operation of said operator element being an
actual operation of the key corresponding to said note-name information.
11. An automatic performance device with tempo follow-up function according
to claim 1 which further comprises:
averaging means inserted between said control data forming means and said
tempo varing means for averaging at least two control data and outputting
averaged control data whose value is a value obtained by averaging the
values of said at least two control data, and wherein
said tempo varying means for varying said tempo in accordance with said
averaged control data.
12. An automatic performance device with tempo follow-up function according
to claim 11 wherein:
said averaging means comprises weighting means for respectively weighting
the values of said at least two control data in accordance with
note-length information corresponding to said at least two control data
before averaging said values of at least two control data.
13. An automatic performance device with tempo follow-up function according
to claim 11 wherein:
said averaging means comprises weighting means for respectively weighting
said values of said at least two control data in accordance with the
outputting order of said at least two control data before averaging said
values of at least two control data.
14. An automatic performance device with tempo follow-up function according
to claim 12 wherein:
said averaging means comprises excluding means for excluding from said at
least two control data one not having a value which falls within a
predetermined allowable range, before averaging said values of at least
two control data.
15. An automatic performance device with tempo follow-up function according
to claim 1 wherein:
said tempo varying means comprises tempo pulse generator for generating
tempo pulses in accordance with said control data, said tempo pulses
having a frequency corresponding to the value of said control data so that
said certain tempo of said automatic performance is varied in response to
said tempo pulses.
16. An automatic performance device with tempo follow-up function according
to claim 1 wherein:
said automatic performance means automatically performs an accompaniment
tone.
17. An automatic performance device with tempo follow-up function according
to claim 16 wherein:
said automatic performance means automatically performs at least one type
of automatic accompaniment tone selected from among an automatic rhythm
tone, automatic bass tone, automatic chord tone and automatic arpeggio
tone.
18. An automatic performance device with tempo follow-up function
comprising:
an operator element,
memory means for storing note-length information of musical tones to be
performed, each said note-length information representing a reference
timing which is a required timing to operate said operator element
readout means for sequentially reading out said note-length information
from said memory means in order of performance at a certain tempo, and
control means connected to said operator element, said memory means and
said readout means, for supplying to said readout means a readout signal
whose period relates to the time difference between the timing of the
operator element operation and said reference timing,
the readout of said readout means being responsive to said readout signal,
and said certain tempo corresponding to the supplying rate of said readout
signal.
19. An automatic performance device with tempo follow-up function according
to claim 18 wherein said control means comprises:
measuring means for measuring an interval of operations of said operator
element in accordance with said note-length information, the period of
said readout signal corresponding to the measured interval.
20. An automatic performance device with tempo follow-up function according
to claim 16 wherein said control means comprises:
measuring means for measuring an interval of operations of said operator
element based on said certain tempo, and
comparing means for comparing said interval with said reference timing
represented by said note-length information, said period of said readout
signal corresponding to the result of the comparison.
21. An automatic performance device with tempo follow-up function according
to claim 18 wherein said control means comprises:
reference timing designating means for designating said reference timing
based on said certain tempo and said note length information; and
comparing menas for comparing said reference timing and the timing of said
operator element operation, said period of said readout signal
corresponding to the result of the comparison.
22. An automatic performance device with tempo follow-up function according
to claim 18 wherein:
said memory means further stores note-name information corresponding to
said note-length information, and
said readout means further reads out said note-name information from said
memory means.
23. An automatic performance device with tempo follow-up function according
to claim 22 further comprising:
musical tome generating means for generating a musical tone in accordance
with said note-length information and said note-name information.
24. An automatic performance device with tempo follow-up function according
to claim 22 wherein said operator element is a key of a keyboard further
comprising:
indicating means for indicating a key to be operated in response to said
note-name information.
25. An automatic performance device including memory means storing musical
data and readout means therefor, said musical data including automatic
performance tone generation timing data, and wherein automatic performance
is carried out in accordance with said musical data successively read out
from said memory means by said readout means, comprising:
keyboard means provided with a plurality of keys for generating a key
relation signal in response to a depressed key among said keys;
tone signal producing means for producing a tone signal in response to said
depressed key;
control means connected to said keyboard means and said memory means for
supplying a control signal, said control signal being generated according
to said key relation signal and to said tone generation timing data;
automatic performance means for generating an automatic performance to
accompany tone signals produced in response to depressed keys; and
a tempo pulse generator for generating tempo pulses, the performance rate
of said automatic performance means being controlled by said tempo pulses;
and wherein
said control means comprises a tempo control circuit for forming difference
data indicative of successive time differences between said key relation
signal and said tone generation timing data and for using said difference
data to control said tempo pulse generator, so that the rate of said tempo
pulses, and hence said automatic performance rate, will be controlled in
response to said difference data.
26. In an electronic musical instrument, an automatic performance device
with a tempo follow-up function, comprising:
note-length data means for providing note-length data of musical tones to
be performed successively, said data representing the desired time
duration between successively performed notes,
player responsive means for producing a response data signal indicative of
the actual timing between playing of consecutive notes,
control data means, cooperating with said note-length data means and said
player responsive means, for providing a control signal indicative of the
temporal relationship between said actual timing as indicated by said
response data signal and said desired time duration between successive
notes as indicated by said note-length data,
automatic accompaniment means for providing an automatic accompaniment in
said instrument, and
tempo adjusting means for adjusting the tempo of said automatic
accompaniment means in response to said control signal.
27. An automatic accompaniment device according to claim 26 wherein said
control data means comprises:
a variable frequency divider for dividing fixed clock rate pulses by an
amount determined by said note-length data,
a counter for counting the divided pulses from said variable frequency
divider, said counter being reset by said response data signal,
consecutive counts of said counter thereby being of constant value when
said response data signal occurs consecutively at timings corresponding to
said desired time duration between successive notes, and
control signal circuit means for providing said control signal in response
to the consecutive count values of said counter, said control signal being
indicative of any variation in said consecutive count values.
28. An automatic performance device according to claim 26 wherein said
tempo adjusting means includes a tempo pulse generator, the tempo of said
automatic accompaniment means being responsive to the rate of tempo pulses
from said generator, and wherein said control data means comprises:
a counter for counting said tempo pulses, said counter being reset by said
response data signal,
subtractor means for determining the difference between a value
corresponding to said note-length data and the contents of said counter,
and
control signal circuit means for providing said control signal in response
to said determined difference, said generator tempo pulse rate being
established by said control signal.
29. An automatic performance device according to claim 26 wherein said
tempo adjusting means comprises a tempo pulse generator, the tempo of said
automatic accompaniment means being responsive to the rate of tempo pulses
from said generator, and wherein said control data means comprises:
a first counter for counting said tempo control pulses, said first counter
being reset upon provision of said note-length data, said first counter
providing a first output signal when the contents thereof reaches a value
corresponding to said note-length data,
second and third counters each incremented by fixed rate clock pulses, said
second counter being reset by said first output signal, said third counter
being reset by said response data signal,
difference means for obtaining the difference between the contents of said
second and third counters just prior to resetting thereof, and
control signal circuit means for providing said control signal in response
to said obtained difference, said generator tempo pulse rate being
established by said control signal. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
This invention relates to an automatic performance device capable of
adjusting the progress of automatic performance in response to the
depression of keys by a performer.
Automatic performance devices in the prior art include those that
automatically perform melody tones or other musical tones, automatically
perform bass and chord tones, automatically perform arpeggio tones, and
automatically perform rhythm tones on the basis of score data stored in a
memory. Another automatic performance device in the prior art is in
combination of some of the above devices. However, in all of these
conventional automatic performance devices, automatic performance is
carried out in the same tempo from start through end once it is initially
set.
Accordingly, in an electronic musical instrument provided with such an
automatic performance device, performance by depression of keys on the
keyboards together with the automatic performance by the automatic
performance device may cause such problem that key depression timing does
not coincide with the progress of the automatic performance. Suppose that
the key depression timing is faster than the progress of the automatic
performance. In this case, if the next key is depressed in accordance with
the length indicated by the next note on the music sheet (score), the
above lead is maintained resulting again in time discrepancy between the
manual and automatic performance in the next tone, and if the next key is
depressed in coincidence with the timing of the automatic performance, the
length of the tone produced becomes longer than what the corresponding
note on the score represents since the tempo in the automatic performance
is constant, i.e., independent of the key depression timing. In case that
the key depression timing lags behind the tempo in the automatic
performance, to the contrary, the equivalent lag remains if the next key
depression timing is taken in accordance with the length of the next note,
and the tone produced is shorter than what the corresponding note
represents.
This independence of the automatic performance according to the prior art
from the manual key depression timing may cause another problem. When a
performer wishes to change the tempo during the performance, a time
discrepancy between the key depression timing and the tempo of the
automatic performance will inevitably occur. If the tempo of automatic
performance can be adjusted in response to the key depression timing, the
discrepancy will be eliminated and the key depression timing becomes
coincident with the tempo in automatic performance. In an automatic
performance device of the prior art, the tempo is adjusted by operating a
tempo adjusting knob of the device. However, the tempo adjustment in the
conventional device is practically impossible during performance since it
involves highly delicate manupilation of the tempo adjusting knob.
SUMMARY OF THE INVENTION
According to this invention, timing at which a musical tone is generated in
automatic performance (automatic performance tone generation timing) is
compared with timing at which a key is depressed in manual performance
(key depression timing). As the result of this comparison, if the
automatic performance tone generation timing is advanced or fast compared
with the key depression timing, the speed of the automatic performance is
increased or the timing is instantaneously advanced, and, if the key
depression timing lags behind the automatic performance tone generation
timing, the automatic performance is temporarily stopped so that the
performance by the key depresslon and the automatic performance proceed at
the same timing.
In addition, the tempo of the performance by the key depression is
detected, and the tempo of the automatic performance is follow-up
controlled based on the tempo thus detected.
The main object of this invention is to provide a new automatic performance
device with tempo follow-up function which does not require tempo
adjustment by a performer during performance.
Another object of the invention is to provide an automatic performance
device in which the progress of the automatic performance is automatically
follow-up controlled in response to the key depression timing.
Still another object of the invention is to provide an automatic
performance device which can automatically control the tempo of automatic
performance so as to follow delicate changes in tempo in the manual
performance when the performer manually plays a musical instrument while
the device of this invention is in the automatic performance of melody
tones, chords, rhythm tones, etc. by reading score data from the memory.
An embodiment of the invention will now be described in detail with
reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 a block diagram of an embodiment of this invention wherein an
electronic musical instrument is provided with automatic performance
functions for melody tones, accompaniment tones and rhythm tones;
FIG. 2 is a preferred block diagram of the fast feed stop control circuit
in detail;
FIG. 3 is a timing chart showing three cases, i.e., the key depression
timing is fast, delayed and coincident with respect to the automatic
performance;
FIG. 4 is a preferred block diagram of the tempo control circuit in detail;
FIG 5 is a block diagram showing another example of the tempo control
circuit;
FIG. 6 is a block diagram showing still another example of the tempo
control circuit;
FIG. 7 is a block diagram of another embodiment of this invention;
FIG. 8 is a block diagram of still another embodiment of this invention;
FIG. 9 is a detailed diagram showing a tempo control circuit in this
invention; and
FIGS. 10 and 11 are time charts illustrating the operation of the tempo
control circuit in FIG. 9.
DESCRIPTION OF PREFERRED EMBODIMENTS
In this specification, the term automatic performance involves displaying a
depressed key or keys on the basis of readout information from the score
data in addition to the above-mentioned automatic performance of melody
tones or other musical tones, automatic performance of bass and chord
tones, automatic performance of arpeggio tones and automatic performance
of rhythm tones as well as automatic performance of tones in combination
with some of these above tones.
Referring to FIG. 1, an embodiment of the invention is applied to an
electronic musical instrument provided with a automatic melody tone
performance function for automatically performing melody tones, an
automatic accompaniment tone performance function for automatically
performing accompaniment tones such as chords and bass tones, and an
automatic rhythm tone performance function for automatically performing
rhythm section tones, these automatic performance functions being carried
out based on the data read out from the recorded data of a magnetic tape
1a provided on a score 1 by means of a score data reader 2. In this
embodiment, the automatic melody tone performance based on the reading of
the score data is for practice purposes of melody performance. Therefore
these melody tones are performed in a low sound volume which is subdued
enough to indicate the key to be depressed subsequently. That is, in this
embodiment the automatic melody tone performance is intended to generate
melody tones always preceding by one tone so as to indicate the key to be
depressed next.
The output of the score data reader 2 which reads the recorded data of the
magnetic tape 1a provided on the score 1 is fed to a data memory 3, and a
data format is selected corresponding to the data thus read. Table 1 shows
an example of the data format.
TABLE 1
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Data Format
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D1: Pitch data TL1,
Length data TL2
D2: . .
. .
. .
Dn - 1: Pitch data TL1
Length data TL2
Dn: End data
______________________________________
As seen in Table 1, each data Di (i=1, . . . , n) consists of a pitch data
TL1 and a length data TL2. The pitch data TL1 consists, for example, of a
7-bit data made up with a 4-bit note code NC and a 3-bit octave code OC,
while the length data consists, for example, of an 8-bit data. Table 2
shows an example of the length data.
TABLE 2
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Length data
Note length
Decimal
Note (binary) representation
______________________________________
Demisemiquaver 0 0 0 0 0 1 1 0
6
Semiquaver 0 0 0 0 1 1 0 0
12
Quaver 0 0 0 1 1 0 0 0
24
Crotchet 0 0 1 1 0 0 0 0
48
Minim 0 1 1 0 0 0 0 0
96
Whole note 1 1 0 0 0 0 0 0
192
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A rest is expressed by setting all bits of the pitch data to "0", while the
end data Dn indicating the end of the data is represented by setting all
bits of the pitch data TL1 and the note data TL2 to "1".
Each data Di is read from the data memory 3 by an address counter 4. The
address counter 4 is reset by the output of a flip-flop 51 of a start-stop
control circuit 5 upon power input. That is, an initial clear signal IC
produced upon power input is being fed via an OR1 to a set terminal S of
the flip-flop 51 in the start-stop control circuit 5, which sets the
flip-flop 51, and initial-clears the address counter 4. In the meantime,
the output of the flip-flop 51 in the start-stop control circuit 5 is
being fed to a disable terminal DIS of the data memory 3, thus making the
data memory 3 nonoperative.
Subsequently, when a start-set switch 52 of the start-stop control circuit
5 is turned on, the output of this start-set switch 52 is differentiated
by a differentiation circuit 53, then is fed to a reset terminal R of the
flip-flop 51, and resets the flip-flop 51. As a result, the address
counter 4 is released from the reset state, and the data memory 3 becomes
ready to operate. The differentiated output (a single pulse) of the
differentiation circuit 53 is applied to the reset terminal R of a
flip-flop 54 through an OR circuit OR2, and sends out a start-set signal
SS by resetting the flip-flop 54. The output Q of the flip-flop 54 is used
as a play signal PL as mentioned later. In this case, a start-set signal
SS (a single pulse) is produced, while the play signal PL remains "0". The
output of the differentiation circuit 53 is applied to a clock terminal CK
of the counter 4 via the OR circuit OR3 as an address clock signal ACK,
causes the address counter 4 to advance one step, and further causes the
first data D1, i.e., a pitch data TL1 and a length data TL2 with respect
to the first sound to be read from the data memory 3. The pitch data TL1
and the length data TL2 read from the data memory 3 are fed to a latch
circuit 6. The latch circuit 6, to a strobe terminal of which the output
of the OR circuit OR3 (address clock signal ACK) mentioned above is being
applied through a delay circuit 7, latches the pitch data TL1 and the
length data TL2 with respect to the first sound by the output of the delay
circuit 7. The pitch data TL1 thus latched by the latch circuit 6 is fed
to a rest detecting circuit 8, a key indication control circuit 91 of a
melody tone forming section 9, and an automatic melody tone forming
circuit 92, while the length data TL2 is applied to a latch circuit 10.
However, since the latch circuit 10 has already recieved the output of the
OR circuit OR3 at its strobe terminal directly without delay, the length
data TL2 with respect to the first sound is not latched. The rest
detecting circuit 8 is for detecting rests, and detects rests by utilizing
the fact that a rest is indicated by setting all bits of the pitch data to
"0" as mentioned before, and produces a rest detection signal RD upon
detection of a rest.
The key indication control circuit 91 of the melody tone forming section 9
is for controlling the indication of the key corresponding to the pitch
data TL1 applied thereto, and becomes ready to operate when a key
indication select switch 93 is turned on, and sends out a key indication
signal to the upper keyboard 94 to indicate the key corresponding to the
applied pitch data TL1. In the upper keyboard 94, indicating lamps are
arranged so as to correspond to each key, respectively (detail is not
shown), and a corresponding lamp lights according to the key indication
signal from the key indication control circuit 91. When the key indication
select switch 93 is OFF, the key indication control circuit 91 becomes
nonoperative, and no key indication is performed in the upper keyboard 94.
The automatic melody tone forming circuit 92 is for forming a melody tone
corresponding to the pitch data TL1 applied thereto. The automatic melody
tone forming circuit 92 becomes ready to operate as a melody tone
automatic performance select switch 95 is turned on, forms a musical tone
signal corresponding to the melody tone indicated by the applied pitch,
and applies the tone signal to a sound system 11 to produce the indicated
melody tone. When the melody tone automatic performance select switch 95
is OFF, the melody tone by the automatic performance is not produced
because the automatic performance melody tone forming circuit 92 becomes
nonoperative.
That is, firstly, the key of the first sound (the key to be firstly
depressed) in the performance is indicated by the indication lamp
corresponding to said key providing that the key indication select switch
93 is ON, and then the first tone (the musical tone to be firstly
produced) in the performance is generated providing that the melody tone
automatic performance select switch 95 is ON. The musical tone produced by
the automatic melody tone forming circuit 92 is a musical tone to be
produced manually by a performer, therefore, normally the melody tone
automatic performance select switch 95 is being turned off or a melody
tone volume control VR1 adjusted to a low volume. The operation will now
be described assuming that the melody tone automatic performance select
switch 95 is set to OFF.
In this state, when the key in the upper keyboard 94 whose indication lamp
is ON is depressed, this depressed key is detected by a key switch circuit
96, and a key code KC (4-bit note code NC plus 3-bit octave code OC)
indicating that said depressed key is delivered from the key switch
circuit 96. The key code KC is fed to a melody tone forming circuit 97.
The melody tone forming circuit 97 forms a musical tone signal
corresponding to the melody tone indicated by the key code KC, applies it
to the sound system 11 via a tone volume control VR2 to produce the
indicated melody tone.
The key code KC delivered from the key switch circuit 96 is applied to a B
input of a comparator 12. The comparato 12 receives the pitch data TL1 of
the data latched by the latch 6 at its A input. When the pitch data TL1
(indicating the tone to be depressed) to be applied to the A input and the
key code KC (indicating the tone depressed) coincide with each other
(A=B), a coincidence signal is output. The coincidence signal is fed to an
AND circuit A1. The AND circuit A1 has another input terminal to which a
signal resulted from the differentiation via the differentiation circuit
13 of a key-on signal KON ("1" when the key is depressed an "0" when the
key is released) delivered from the key switch circuit 96 has already been
fed, and outputs a pulse (key depression coincidence signal) KEQ
synchronized with the key depression under the condition that the key
whose indication lamp is ON is depressed. The key depression coincidence
signal KEQ is fed to a fast feed stop control circuit 15 and is also fed
to a set terminal S of the flip-flop 54 and an AND circuit A2 via a select
switch 14. The select switch 14 is for selecting whether or not a mistouch
in the key depression is removed. When the select switch 14 is in the
position as shown in FIG. 1, no key depression coincidence signal KEQ is
produced if the key depression is a mistouch, i.e. if the key in the upper
keyboard whos indication lamp is ON does not coincide with the depressed
key. On the other hand, when the select switch 14 is switched in the other
position, a key depression coincidence signal KEQ is produced via the
select switch 14 even if the key depression is a mistouch. The operation
will now be described assuming that the select switch 14 is in the
position as shown in FIG. 1.
The quick feed stop control circuit 15 does not operate even if the first
key depression coincidence signal KEQ is fed. However, since the flip-flop
54 of the start-stop control circuit 5 has been reset, and the AND circuit
A2 to which a play signal PL delivered from the flip-flop 54 is applied
through a delay flip-flop DF1 and an inverter IN1 is ready to operate, the
key depression coincidence signal KEQ is applied to the OR circuits, OR3
and OR4. Accordingly, an address clock signal ACK is outputted from the
output of the OR circuit OR3 thereby causing the address counter to
advance one step, while the output of the OR circuit OR4 is fed to a tempo
control circuit 16 as a key-on timing signal KOT. This key-on timing
signal KOT is for controlling a tempo pulse TP produced at the tempo
control circuit 16 as mentioned later.
The flip-flop 54 is set by the first key depression coincidence signal KEQ,
and the play signal PL rises to "1". Accordingly, the signal to be fed to
the AND circuit A2 through the delay flip-flop DF1 and the inverter IN1
becomes "0" one clock time after the rise of the play signal PL, the AND
circuit A2 becomes nonoperative, and the subsequent passage of the key
depression coincidence signal KEQ in the AND circuit A2 is inhibited.
Since the output of the OR circuit OR3 is fed to the strobe terminal of the
latch circuit 10, the length data TL2 with respect to the first tone
latched by the latch circuit 6 is latched by the latch circuit 10.
As the address counter 4 is advanced one step by the first key depression
coincidence signal KEQ, the data D2 with respect to the second tone (pitch
data TL1 and length data TL2) is read from the data memory 3, and this
data D2 is latched at the latch circuit 6 by the output of the OR circuit
OR3 delayed by the delay circuit 7. The pitch data TL1 of the data latched
by the latch circuit 6 is fed to the rest detecting circuit and the melody
tone forming circuit 9, and performs the rest detection and ON-OFF control
of the indication lamp provided on the key of the tone to be produced
next. These controls are conducted in the same manner as in those
described previously.
A play signal PL produced from the start-stop control circuit 5 is fed to
the tempo control circuit 16. The tempo control circuit 16 forms a tempo
pulse TP which determines the tempo of the automatic performance in this
embodiment, and the initial tempo pulse set in advance is outputted
providing that a play signal PL is produced in the initial state.
(Detailed circuit composition is explained later). The tempo pulse TP is
fed to the clock terminal CK of a rhythm counter 17 through the AND
circuit A3 and the OR circuit OR5.
The rhythm counter 17 counts tempo pulses TP, and controls the progress of
the automatic accompaniment tone performance mentioned below. Said rhythm
counter 17 is so constructed as to be set initially by the output of a
flip-flop 19 which is set by the above mentioned play signal PL
differentiated at a differentiation circuit 18. A stop switch 20 is for
stopping the automatic accompaniment tone performance, and the flip-flop
19 is reset as the stop switch 20 is turned on, thereby making the rhythm
counter 17 nonoperative.
The output of the rhythm counter 17 is fed to a rhythm pattern generator
circuit 211 of an accompaniment tone forming section 21. The rhythm
pattern generator circuit 211 includes a ROM which stores the
predetermined performance pattern by taking the output of the rhythm
counter 17 as the address signal of the ROM, and sequentially generates
pattern pulse based on said performance pattern corresponding to the
output of the rhythm counter 17. Pattern pulses generated by the rhythm
pattern generator circuit 211 are fed to an accompaniment tone forming
circuit 212 and a rhythm tone forming circuit 213.
The accompaniment tone forming circuit 212 detects a depressed key in a
lower keyboard 217, detects the output of a key switch circuit 214 and the
key depressed at a pedal keyboard 215, receives the output of a key switch
circuit 216 which outputs the key information about said key, and forms
musical tone signals corresponding to accompaniment tones, such as chord
tones, bass tones, and arpeggio tones, based on the key information and
the pattern pulses sequentially outputted from the rhythm pattern
generator circuit 211 to apply these signals to the sound system 11 via a
tone volume control VR3.
The rhythm tone forming circuit 213, which becomes in the enable state when
a select switch 21a turns ON, is for opening and closing multiple rhythm
tone sources based on the pattern pulses generated at the rhythm pattern
generator circuit 211 to form musical tone signals corresponding to the
rhythm tones, which is fed to the sound system 11 via a tone volume VR4
and converted into rhythm tones by the sound system 11. Therefore, when
the select switch 21a is set to ON, rhythm tones are automatically
generated in synchronism with the manual performance by the upper keyboard
94 and the automatic rhythm performance stops upon the depression of the
stop switch 20.
Since various known devices may be used for forming accompaniment tones,
such as chord tones, base tones, and arpeggio tones, based on the key
information from the lower keyboard and the pedal keyboard as well as on
the pattern pulses, and for forming rhythm tones based on the pattern
pulses, detailed structural description thereon is omitted.
Musical tone signals indicating the accompaniment tones thus formed at the
accompaniment tone forming section 21 are fed to the sound system 11, and
musical tones are produced.
When a key in the upper keyboard 94 whose indication lamp has lit is
depressed under the condition that the lit indication lamp corresponds to
the second tone and the automatic accompaniment tone performance has
started, a coincidence signal is produced at the comparator 12, the AND
circuit A1 becomes ready to operate, and the key depression coincidence
signal KEQ is fed to the fast feed stop control circuit 15 via the select
switch 14.
The fast feed stop control circuit 15 judges whether the key depression
timing in the upper keyboard 94 is leading or lagging based on the length
data TL2 latched by the latch circuit 10, outputs a fast feed signal FF
when said key depression timing is fast, and outputs a stop signal ST when
said timing is delayed. This fast feed signal FF is fed to an AND circuit
A4, and is also fed to the AND circuit A3 after being inverted at the
inverter IN2. As a result, the AND circuit A3 becomes nonoperative, the
AND circuit A4 becomes ready to operate, and a high speed clock pulse
.phi. is outputted as a tempo pulse TP through the AND circuit A4 and the
OR circuit OR5. Accordingly, the automatic performance is advanced rapidly
so that the progress of the automatic performance and the key depression
timing coincide with each other. Further, the stop signal ST is applied to
the AND circuits A3 and A4 after being inverted by inverter IN3. As a
result, these AND circuits A3 and A4 become nonoperatable, whereby tempo
pulses outputted from the OR circuit OR5 is halted, thus the progress of
automatic performance is halted. As will be apparent from description to
be made later, this halt of automatic performance lasts until the next key
depression is made and therefore enables the progress of the automatic
performance to coincide with the key depression timing.
Preferred configuration of the said fast feed stop control circuit 15 is
shown in FIG. 2 in detail.
In FIG. 2, since a counter 151 has received the output of the OR circuit
OR3 (FIG. 1) at its reset terminal R and a tempo pulse TP at its clock
terminal CK, the counter 151 is reset synchronized with the output of the
OR circuit OR3 (the key depression timing of the first tone in the above
case), and counts tempo pulses subsequently.
In a comparator 152, the output of the counter 151 is fed to its B input,
and the output of the latch circuit 10 (FIG. 1) is fed to its B input. As
apparent from the above description, the information latched by the latch
circuit 10 is the length data TL2 with respect to the first tone. The
comparator 152 compares the length data TL2 fed to the A input thereof
with the count value of the counter 151, outputs a signal "1" to a line
153 if A>B, and outputs a signal "1" to a line 154 if A=B.
The key depression timing with respect to the second tone can be fa | | |
