JPS6325696A - Electronic musical instrument - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electronic musical instrument that can easily set an envelope and generate good musical tones.

2. Description of the Related Art A waveform memory read method is available as an electronic musical instrument in which the pitch of a generated musical tone is determined by an accumulated value obtained by repeatedly accumulating step data corresponding to the pitch of a pressed key at a constant speed.

Figure 3 shows an example of the configuration of an electronic musical instrument using the conventional waveform memory reading method. , has a key switch corresponding to each key of the keyboard section, and when a certain key is pressed, the corresponding key switch operates and a signal with a logical value of 51' is output to its output line.In this case,
The key switch circuit 14 has a built-in single-note priority circuit, so that when multiple key switches operate at the same time, only the output line corresponding to the key switch with the highest priority is set to ``11''.
A signal is now output.

Further, this key switch circuit 14 is configured to output a key-on signal KON indicating that a certain key is pressed. The output line corresponding to each key switch of the key switch circuit 1 is connected to the input side of a frequency information memory 15, and the memory 15 stores numerical step data STD corresponding to the pitch of each key. . Therefore,
When a certain key is pressed, step data STD corresponding to the pitch of that key is read from the frequency information memory 15.

The step data STD read from the frequency information memory 15 is supplied to the accumulator 16, and the accumulator 16 sequentially accumulates the step data STD in synchronization with the clock pulse φ of a constant frequency X+1, and calculates the accumulated value qSTD. (q=1.2°3...N) are sequentially outputted as three sale address signals of the waveform memory 17. In the waveform memory 1, each sample point amplitude value of one period of the desired musical tone (sound source) waveform is stored at each address, and is stored at the address specified by the read address signal (cumulative value qsTD) from the accumulator 16. The waveform amplitude values that are displayed are sequentially read out.

As is clear from the above description, the step data STD corresponding to the pressed key is read out from the frequency information memory 16, and is accumulated in the accumulator 16 at the timing of the clock pulse φ of a constant period. The value qSTD becomes the read address signal of the waveform memory 17. Therefore, the waveform memory 1 outputs a musical tone (sound source) waveform UW having a frequency corresponding to the pitch of the pressed key. On the other hand, the envelope waveform generator 19 receives the key-on signal KON output from the key switch circuit 14 and generates an envelope waveform ENV for volume envelope control. The musical sound waveform MW read from the waveform memory 1 is then supplied to the multiplier 18 and multiplied by the envelope waveform ENV output from the envelope waveform generator 19, thereby giving a volume envelope to the musical sound waveform MY. . The musical sound waveform with this volume envelope)! W' is further supplied to a sound system 2OK consisting of an amplifier, a speaker, etc., and is produced as a performance sound.

Therefore, the sound system 20 outputs the waveform shape (timbre) at the frequency (pitch) determined by the step data STD read from the frequency information memory 15 in response to the pressed key, and the waveform shape (timbre) stored in the waveform memory 1. A musical tone is generated.

Problems to be Solved by the Invention As is clear from the above explanation, the conventional electronic musical instrument as described above generates step data STD corresponding to a pressed key, and converts this step data STD into a clock pulse φ having a constant period. is sequentially accumulated in the generator to form an accumulated value qs'rn specifying each sample point of the musical sound waveform. Therefore, the pitch of the generated musical tone is determined by the step data STD, but on the other hand, the envelope waveform is generated by the υ envelope waveform generator by inputting the key-on signal, and the musical tone (sound source) obtains an envelope waveform corresponding to the shape. This method has the disadvantage that the control constants of the envelope waveform generator must be changed every time the musical tone (sound source) waveform is changed.

The present invention has been made in view of the above-mentioned conventional waveform memory reading method, and provides an electronic musical instrument that can easily obtain an envelope waveform corresponding to a sound source (timbre) waveform.

Means for Solving the Problem To achieve this object, the electronic musical instrument of the present invention accumulates numerical step data corresponding to the pressed keys at a constant speed,
The configuration is configured to read musical tone and shape data from the waveform memory using the value obtained by adding this accumulated value and the octave data corresponding to the range as an address, and allocates different waveform memories corresponding to the range, and also Envelope containing level target value and ode data).

- data is stored, and a volume envelope is generated based on this data.

Operation The present invention can obtain an envelope waveform corresponding to a sound source (timbre) waveform with a simple configuration by storing envelope control data in the waveform memory using the above-described configuration.

Example Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a block diagram showing an example of the configuration of an electronic musical instrument using a waveform memory reading method according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a key switch circuit provided in the keyboard section, which has a key switch corresponding to each magazine of the keyboard section, and when a certain key is pressed, the corresponding key switch is activated. A signal with a logic value of "1" is output to the output line.

The key switch circuit 1 is still configured to output a key-on signal KON indicating that a certain key is pressed. The output line corresponding to each key switch of the key switch circuit 1 is connected to the input side of the frequency information memory 2, and the frequency information memory 2 contains step data STD and octave data OC of numerical values corresponding to the pitch of each magazine.
T is memorized. Therefore, when a certain key is pressed, step data STD and octave data OCT corresponding to the pitch of that key are read out from the frequency information memory 2.

The octave data OCT read from the frequency information memory 2 is supplied to the accumulator 3, and is used to select a desired musical tone (sound source) waveform corresponding to the pitch. On the other hand, the step data STD read from the frequency information memory 2 is supplied to the accumulator 3, and the accumulator 3 sequentially accumulates the step data STD in synchronization with the clock pulse φ, and calculates the accumulated value qSTD.
(c4=1.2.3...N) and the start address of the musical sound (sound source) waveform memory area corresponding to the range given as octave data OCT are added, and the result is sequentially read out as the read address signal RDADH of the waveform memory 4. Output. In the waveform memory 4, the amplitude and width values of each sample of one cycle of the desired musical tone (sound source) waveform are stored at each address according to the tone range, and are specified by the read address signal (RDADH) from the accumulator 3. The waveform amplitude values stored at the addresses are sequentially read out.

The storage format and contents of musical tone (sound source) waveforms stored in the waveform memory 4 will be explained with reference to FIG. In FIG. 2, 8 to 12 indicate the storage format of the amplitude value of each sample point of one period of the musical tone (sound source) waveform corresponding to each musical range (indicated in octave units here).
8 is the musical tone (sound source) waveform for the first octave, and 9 is the waveform for the second octave.
1o is the musical tone (sound source) waveform for the 3rd octave, 11 is the musical tone (sound source) waveform for the 4th octave, 12 is the musical tone (sound source) waveform for the 5th octave. 13 is an envelope control data memory area (hereinafter referred to as memory area) that stores envelope generation control constants.

Then, in the memory 8 of the musical tone (sound source) waveform for the first octave, the musical tone (sound source) waveform of 1 period or 1/2 period consisting of the 1st (fundamental wave) to the 2nd nth harmonic is sampled. It is stored as 2m.

Memory areas 9 to 12 each have memory area 8.
Similarly, musical tone (sound source) waveforms are stored, but each time the corresponding range goes up one octave, the highest order of harmonics that make up the musical tone (sound source) waveform and the number of sample points of the musical tone (sound source) waveform are reduced by 1/2. It becomes. From this, it can be seen that as the range becomes higher, the number of harmonic orders included in the waveform read from the waveform memory 4 decreases.

As a result, in the waveform memory readout method in which sample point amplitude values of one cycle of the waveform stored in the waveform memory 4 are read out at a constant cycle, when the step interval of sample points is increased, the frequency of harmonics included in the waveform becomes higher. It is possible to prevent aliasing noise caused by this.

As is clear from the above description, the step data STD and octa-data OCT corresponding to the pressed key are read out from the frequency information memory 2, and the step data STD and octa-data OCT are read out from the frequency information memory 2.
D is accumulated in the accumulator 3 at the timing of the clock pulse φ of a constant period, and the result of adding the accumulated value qSTD and the start address of the memory area corresponding to the range given as octave data OCT is read out from the waveform memory 4. It becomes an address signal. Therefore, the waveform memory 4 outputs a musical tone (sound source) waveform MY having a frequency corresponding to the pitch of the pressed key.

On the other hand, the envelope waveform generator 6 is connected to the key switch circuit 1.
The key-on signal KON outputted from the waveform memory 4, the level target value in the envelope control data ECD outputted from the waveform memory 4, the slope data α, and the current envelope data value E. The next envelope data value E+1 is generated from, for example, the following equation.

K to E+. +(D-Ko) US α-t, D-Eo= otD time'd-Update the envelope control data ECD. However, the level target value in the envelope control data ECD on the return trip is O. This generates an envelope waveform ENV for volume envelope control in accordance with the musical tone (sound source) waveform. Then, the musical waveform MW read out from the waveform memory 4 is supplied to a multiplier 5, and an envelope waveform generator 6
The sound waveform MW is multiplied by the envelope waveform ENV output from the musical tone waveform MW, thereby imparting a volume envelope to the musical tone waveform MW.

The musical sound waveform MW' to which the volume envelope has been applied is further supplied to a sound system 7 comprising an amplifier, a speaker, etc., and is produced as a performance sound.

Therefore, the frequency (pitch) determined by the step data STD and octave data OCT read from the frequency information memory 2 in response to the pressed key, and the waveform shape stored in the waveform memo 1J44. A musical tone (timbre) is generated, and the waveform memory 4 is also multiplied by the envelope i-type E N 'i for volume envelope control generated under the control of the envelope control data read out by the multiplier 5 to give a volume envelope. A musical sound waveform M W ' is output.

Effects of the Invention As described above, according to the present invention, by storing envelope control data in a waveform memory, an envelope waveform corresponding to a sound source (timbre) waveform can be obtained with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of an electronic musical instrument according to the present invention, FIG. 2 is a format diagram of a waveform memory of an electronic musical instrument according to an embodiment of the present invention, and FIG. It is a block diagram showing an example of a musical instrument. 1...Key switch circuit, 2...Frequency information memory, 3...Accumulator, 4...
Waveform memory, 5... Multiplier, 6... Envelope waveform generator, 7... Sound system, 8-1
2... Range-compatible musical tone (waveform) data memory area, 13... Envelope control data memory area. Fig. 1 Fig. 3

Claims (3)

[Claims] (1) An electronic musical instrument that repeatedly accumulates numerical step data corresponding to the pitch of a pressed key at a constant speed, and uses this accumulated value to control the pitch of a generated musical sound, which key is pressed. Frequency information generation means for generating step data corresponding to the pitch of a pressed key, pitch range information generation means for generating octave data corresponding to the pitch of the pressed key, and step data generated from the frequency information generation means at a constant rate. an accumulating means for repeatedly accumulating data, an adding means for adding the accumulation result and octave data generated from the range information generating means, musical tone (sound source) waveform data corresponding to the musical range, and this musical tone (sound source). An electronic musical instrument comprising a waveform memory storing waveform data and envelope control data, the waveform memory consisting of 2^a pieces of data. (2) The electronic musical instrument according to claim 1, wherein the envelope control data consists of 2^b pieces of data, and one piece of data consists of a level target value and slope data. (3) The electronic musical instrument according to claim 1, wherein the final value of the level target value in the envelope control data is zero.