JPS595911B2 - electronic musical instruments - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an electronic musical instrument, and in particular, to prevent the cancellation of generated musical tones that occurs when keys of the same pitch are pressed simultaneously on multiple keyboards such as the upper keyboard and the lower keyboard. This article concerns an improved electronic musical instrument.

Recently, with the development of integrated circuit technology, electronic musical instruments that generate musical tones using digital technology have been proposed.

Various methods have been considered for this digital electronic musical instrument, and FIG. 1 shows an example of an electronic musical instrument that uses a waveform memory to generate musical tones. The electronic musical instrument shown in FIG. 1 is, for example, Japanese Patent Application No. 48-41964
Since it is explained in detail in the specification (No. 9-130213), its outline will be explained below. In FIG. 1, 1 is a key switch circuit for the upper keyboard, lower keyboard, and pedal keyboard, 2 is a key assigner, 3 is a frequency information storage device, 4 is a gate circuit, 5 is an accumulator, 6 is a waveform memory, and 7
8 is an envelope waveform generator, 8 is a clock pulse generator, and 9 is a sound system consisting of a tone circuit, an expression circuit, an amplifier, a speaker, and the like.

The key assigner 2 detects the on or off operation of the key switch of each key in the key switch circuit 1 by sequential scanning based on the clock pulse (frequency fo) from the clock pulse generator 8, and provides information for identifying the pressed key. is assigned to one of the channels corresponding to the number of simultaneous sounds (for example, 12 notes).

This key assigner 2 stores the key date month 1 representing each pressed key in a storage location corresponding to each channel, and sequentially outputs the key data KD stored in each channel in a time-division manner. Therefore, when multiple keys are pressed simultaneously on each keyboard, each pressed mirror is assigned to a separate channel, and the memory location corresponding to each channel contains key data representing the assigned key. KD is stored respectively. Each storage location can be configured by a circular shift register. For example, the key data KD that specifies each key in each keyboard section includes 2-bit keyboard codes K2, Kl that represent the keyboard type, and 3-bit octave codes B3, B2 that represent the octave range, as shown in Table 1 below.
, Bl, and 4-bit note codes N4, N3, N2, and Nl that represent note names within one octave.The total number of channels is 12.
If so, it is preferable to use a 12-stage (1 stage=9 bits) shift register. Therefore, the key data KD representing the key assigned for sound generation by the key assigner 2 (that is, the key data stored in the shift register) is sequentially output in a time-division manner in accordance with the assigned channel time. . Further, the key assigner 2 outputs an envelope start signal ES indicating that a sound should be generated in the channel to which the pressed key is assigned a sound at the channel time. Further, the key assigned to each channel is released, and a decay start signal DS indicating that the sound generation should be attenuated is outputted at the time of the corresponding channel. The envelope waveform generator 7 is used for these purposes (sound control). Furthermore, the key assigner 2 receives a decay end signal DF from the envelope waveform generator 7 indicating that the sound generation in each channel has ended (the decay has ended), and based on this signal DF, clears various memories related to the channel. Then, it enters a standby state for pressing a new key. The frequency information storage device 3 is a memory that receives the key data KD from the key assigner 2 and outputs corresponding frequency information values F as shown in Table 2 below, for example.

In this frequency information bit, 1 bit is represented by an integer part and the other 14 bits are represented by a decimal part. In this Table 2, the F number is a value obtained by converting the numerical value F expressed in binary to a decimal number. The output F of this frequency information storage device 3
is led to an accumulator 5 via a gate circuit 4 controlled by a clock pulse φ.

The accumulator 5 is an accumulator that accumulates the numerical value F for each channel, and 12 stages for holding the accumulated value for 12 time slots (corresponding to the number of simultaneous polyphony) until the next accumulation of the channel. It is equipped with a temporary memory circuit.

For example, the integer output of the upper 6 bits (accumulated value QF) of this accumulator 5 is supplied to a waveform memory 6 to control reading of this waveform memory 6. Note that the lower bits of the accumulator 5 are used only for accumulation. The waveform memory 6 stores the amplitude of one waveform of a desired musical tone divided into, for example, 64 along the time axis, and the waveform amplitude values of the address numbers corresponding to the cumulative value QF from the accumulator 5 are sequentially read out. be done.

The musical sound waveform read from the waveform memory 6 is multiplied by an envelope waveform such as attack or decay from an envelope waveform generator 7, and then appropriately controlled in tone and volume by a sound system 9 and produced as a performance sound. In this case, the envelope waveform generator 7 generates envelope waveforms such as attack and decay based on the envelope start signal ES and the decay start signal field from the key assigner 2. Note that when a certain frequency information value F is output from the frequency information storage device 3 in response to a certain key data KD, the modulus of the accumulator of the accumulator 5 is M, and the maximum number of simultaneous polyphonic sounds is N. given that,
Frequency of musical sound waveform read from waveform memory 6 When playing such an electronic musical instrument, normally the upper keyboard is used to play melody, the lower keyboard is used to play chords, and the pedal keyboard is used to play bass.

For example, in the above-mentioned electronic musical instrument having 49 keys on the upper keyboard, 49 keys on the lower keyboard, and 17 keys on the pedal keyboard, as shown in FIG. The pedal keyboard plays the high C1 to C5 range, and the pedal keyboard plays the pitch C1 to E.
They each share the two tonal ranges. Therefore, for example, if keys with pitch A4 are pressed on the upper and lower keyboards at the same time, musical tones of 440 Hz will be produced corresponding to pitch A4, but in this case, the notes corresponding to both keys will be sounded at 440 Hz. If the generated musical tone signals become out of phase with each other for some reason, there is a risk that the two signals will cancel each other out and no longer be produced as a musical tone. This invention was made in order to eliminate the above-mentioned drawbacks, and is designed so that when keys of the same pitch on multiple keyboards such as the upper and lower keyboards are pressed at the same time, the two do not cancel each other out. The purpose is to provide an electronic musical instrument with a

That is, the present invention provides an electronic musical instrument that has a plurality of keyboards and is configured to generate musical tone signals corresponding to the pressed keys of each keyboard. a plurality of pitch setting means for selecting and setting an arbitrary pitch deviation amount from among the plurality of pitch deviation amounts; a plurality of pitch control signal generating means for generating pitch control signals having slightly different values for each keyboard;
The pitch control signals for each of the keyboards generated by the pitch control signal generating means control the pitch of the tone signal of the corresponding keyboard.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is an overall block diagram showing an embodiment of the electronic musical instrument of the present invention, and in this figure, the same parts as those in FIG. 1 are given the same numbers and their explanations will be omitted.

In the figure, 10 is a multiplier connected between the frequency information storage device 3 and the gate circuit 4;
multiplies the numerical signal F from the frequency information storage device 3 by a pitch control signal P, which will be described later, and inputs the output to the accumulator 5 via the gate circuit 4. 11u, 11
Pitch setting devices L and 11p are respectively provided corresponding to the upper keyboard, lower keyboard, and pedal keyboard constituting the key switch circuit 1, and the pitch setting devices 11u and 11
L, 11p are pitch selection switches 12u, 12L, 12
p and memos January 3u, 13L, and 13p, respectively.

Each pitch selection switch 12u, 12L, 12p has a movable terminal a to which a signal "B" is supplied and five fixed terminals b-f, and the fixed terminals b-f correspond to the set position of the movable terminal a.
The signal from f is input as an address designation signal to the memories 13u and 13L and 13p, respectively.

These memos 3u, 13L, and 13p are preset with desired numerical signals, that is, pitch control signals Putsu PL, so as to vary the pitch of the musical tones to be generated according to the settings of the pitch selection switches 12u, 12L, and 12p. This is a memory of PP.

For example, in each memo 1 river 3u, 13L, 13p,
When setting fixed terminal b of pitch selection switches 12u to 12p, +10 cents, fixed terminal c +5 cents, fixed terminal d ('O cents, fixed terminal e -5 cents, fixed terminal f
Pitch control signal Pu corresponding to -10 cents at
-Pp is output according to the switching settings of the pitch selection switches 12u to 12p. In this case, the pitch control signals PU, PL, PP stored in the memories 13u, 13L, 13p respectively have the same general fixed value (±
10 cents, ±5 cents, and 0 cents), the values are slightly different from each other. That is, the pitch control signals PU, PL, and PP at +10 cents have slightly different values (the same applies to the other set values +5 cents, 0 cents, -5 cents, and -10 cents). 1
A decoder 4 inputs a 2-bit keyboard code K2, Kl representing the type of keyboard out of the key data KD obtained from the key assigner 2, and this decoder 14 inputs a 2-bit keyboard code K2, Kl representing the type of keyboard. A signal UE1 indicating that the key is related to the lower keyboard, a signal LE indicating that the key is related to the lower keyboard, and a signal PE indicating that the key is related to the pedal keyboard are generated, respectively.

Reference numeral 15 denotes a gate circuit that continuously controls pitch control signals PU, PL, and PP obtained from pitch setters 11u, 11L, and 11p in accordance with output signals UE, LE, and PE from the decoder 14, respectively. It is composed of three Gero 5u, 15L, and 15p.

In this case, the game port 5u has a memory 13u as an input signal.
The pitch control signal Pu from the memory 13p is supplied to the gate 5L, the pitch control signal PL from the memo 1 river 3L and the signal LE are supplied to the gate 5L, and the pitch control signal Pu from the memory 13p is supplied to the gate 15L. A signal Pp and the signal PE are respectively supplied. Note that the pitch control signal P (Pu, PL,
Pp) is input to the multiplier 10 described above. In an electronic musical instrument configured in this way, each key of the upper keyboard, lower keyboard, and pedal keyboard is divided into ranges as shown in Figure 3,
In addition, when the pitch selection switches 12u and 12L are set as shown, the signals "1" from the fixed terminals d of the pitch selection switches 12u and 12L are input to the memories 13u and 13L, respectively, and each memory In response to these signals, I-rivers 3u and 13L supply pitch control signals Pu and PL representing O cents to gates 15u and 15L.

In this state, if keys with the same pitch on the upper and lower keyboards are pressed at the same time, each key is assigned to a different channel in the key assigner 2, and synchronized with the assigned channel time. Then, key data KD is sent out. The key data KD sent from the key assigner 2 is supplied to the frequency information storage device 3, and a numerical value F corresponding to the key data KD is output (in this case, since each operating key has the same pitch, the numerical value F is the same). ).

The keyboard codes K2 and Kl of the key data KD from the key assigner 2 are supplied to the decoder 14, and the decoder 14 outputs the signal UE in synchronization with the channel time to which the operation key on the upper keyboard is assigned, and the operation key on the lower keyboard. A signal LE is output in synchronization with the channel time to which the key is assigned. As a result, the gates 5u and 15L are turned on in synchronization with the channel time when the signals UE and LE are sent, respectively, and are multiplied by the pitch control signals Pu (0 cents) and PL (0 cents) from the pitch setters 11u and 11L. 10.

The multiplier 10 receives this pitch control signal Pu (0 cents),
PL (0 cents) is multiplied by the numerical value F sent from the frequency information storage device 3 in synchronization with each channel time. In this case, the numerical values F corresponding to the operation keys on the upper and lower keyboards are the same, but the pitch control signals Pu and PL have slightly different values (although they are very close) as described above. Each multiplication output from the multiplier 10 has a slightly different value for each keyboard. Therefore, the musical sound waveforms corresponding to the operating keys of the upper keyboard read from the waveform memory 6 and the musical sound waveforms corresponding to the operating keys of the lower keyboard are basically the same pitch, but have slightly different pitches.
As a result, even if keys of the same pitch are pressed simultaneously on the upper and lower keyboards, each tone signal will not cancel out. In addition, the pitch selection switches 12u, 12L and 12p
The above explanation is also the same when the keys are switched to other positions, and when keys of the same pitch are pressed simultaneously on the lower keyboard and the pedal keyboard.

Of course, if the pitch selection switches 12u, 12L, and 12p are set to different positions, or if keys of different pitches are pressed simultaneously on each keyboard, the pitches of the musical tone signals generated are originally different, so each The problem of cancellation of musical tone signals does not arise. Incidentally, it is conceivable that the numerical value F stored in the frequency information storage device 3 may be slightly different for each keyboard as a means of preventing cancellation of musical tone signals generated corresponding to each keyboard, but in this case, all This results in storing as many numerical values F as the number of keys, which increases the capacity of the storage device 3, which is undesirable. As described above, in this invention, a pitch setting device is provided for each of a plurality of keys, and the pitch setting value by the pitch setting device is slightly different for each keyboard, so that the pitch of each keyboard is the same. Even if two keys are pressed at the same time, cancellation of musical tone signals can be reliably prevented.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventionally used electronic musical instrument, FIG. 2 is a block diagram showing an embodiment of the electronic musical instrument of the present invention, and FIG. 3 is a block diagram of each of the electronic musical instruments shown in FIGS. 1 and 2. FIG. 3 is a diagram showing an example of a keyboard range. 1... Key switch circuit, 2... Key assigner, 3... Frequency information storage device, 4...
...Gate circuit, 5...Accumulator,
6...Waveform memory, 7...Envelope waveform generator, 8...Clock pulse generator,
9... Sound system, 10... Multiplier, 11... Settch setting device, 12u, 12L,
12p...Pitch selection switch, 13u, 13
L, 13p...Memory, 14...Decoder, 15...Gate circuit.

Claims (1)

[Claims] 1. In an electronic musical instrument that has a plurality of keyboards and generates musical tone signals corresponding to the pressed keys of each keyboard,
a plurality of pitch setting means provided corresponding to each of the keyboards and for selecting and setting an arbitrary pitch deviation amount from a plurality of pitch deviation amounts that are the same for each keyboard; a plurality of pitch control signal generating means each generating a pitch control signal corresponding to the pitch deviation amount and having a slightly different value for each keyboard for the same pitch deviation amount; An electronic musical instrument characterized in that the pitch control signal for each of the keyboards generated by the generating means controls the pitch of the musical tone signal for each corresponding keyboard.