JPS6236693A - Musical sound generator - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a musical tone generation device that adds noise to a musical sound wave shape and outputs the same.

[Prior Art] Adding noise to a musical sound waveform is often done to generate percussion instrument sounds and the like.

Conventionally, musical sound generation devices that add noise to musical sound waveforms have been realized by adding or multiplying noise data to waveform data, and further multiplying the calculation output by envelope data to generate musical sounds and emit sounds. has been made into

[Problems with the prior art] However, in this type of device, in order to generate musical tones by adding noise to the waveform data, it is necessary to have a bit for noise data in the circuit, which increases the amount of time and effort required for data processing. In addition, the number of bits of a D/A converter for D/A converting musical tone data increases, resulting in an increase in circuit scale.

[Object of the Invention] Therefore, the object of the present invention is to create a musical sound that does not require a special data beat for noise when adding noise to a musical sound waveform, has a compact circuit, and can perform data processing quickly. The purpose is to provide a generating device.

[Summary of the Invention] To achieve this object, the present invention provides waveform data
-r- Noise is added to the envelope data, and the main point is that the noise is added so that the amplitude level of the noise changes arbitrarily to generate and emit musical sounds. It is something to do.

[Summary of the Invention] Fig. 1 shows an outline of the invention, in which an address is sequentially counted from the readout means 51 to the waveform data storage means 52 under the control of the CPUI, and whose contents change at a speed according to the scale frequency. Data D3! waveform data D
5 are sequentially read out and added to the envelope control means 54, and envelope data D9 is sent from the CPU to the envelope control means 54 via the noise addition means 53.
When the noise addition signal D8 is applied to the envelope data D9, noise is added to the envelope data D9 by the noise addition means 53, and the transformed envelope data Dll is applied to the envelope control means 54. The envelope control means 54 converts the waveform data D5 into modified envelope data Dll.
are superimposed, and musical tones are outputted via the output means 55.

[Configuration of Embodiment] Hereinafter, one embodiment of the present invention will be described in detail with reference to one drawing.

Overall circuit configuration> Figure 2 shows the overall circuit configuration of the musical tone generation device. In the figure, l is a CPU, and this CPU inputs key operation instructions for a keyboard (not shown) etc. to a shift register 3 via a latch 2. Frequency data DI is preset according to. The frequency data Di is then supplied from the shift register 3 to the frequency counter 4 in units of 11, 1 for each channel. This frequency counter 4 performs a predetermined operation based on the supplied frequency data Di, for example, its contents are incremented or decremented at predetermined timings, and a carry signal (or 5 or borrow signal) is outputted to the address counter 5 as an increment signal D2. be done. This increment signal D2 is output at a speed corresponding to the frequency data DI. The address counter 5 sequentially increments address data D3 for reading to the waveform memory 7 every time the increment signal D2 is applied from the frequency counter 4, and supplies this address data D3 to the waveform memory 7 via the address conversion circuit 6. .

This address conversion circuit 6 is given conversion data D8 from the CPU 1 via a latch 8 and a shift register 9 in accordance with the designation of waveform conversion. 2...
The address data D3 that is incremented as 7.4, l, 2, etc. is converted into converted address data D4 and given to the waveform memory 7, and the waveform data D5 of the waveform memory 7 is read out. The order is being changed.

A plurality of types of waveform data are stored in the waveform memory 7, and each waveform data is selected and designated by timbre designation data D7 provided from the CPU via the latch IO and the shift register 11. The waveform data D5 read from the waveform memory 7 is sent to the waveform data conversion circuit 1.
In step 2, the waveform is further transformed into modified waveform data D6, which is multiplied by modified envelope data Dll, which will be described later, in a multiplier circuit 13 to obtain musical tone data 012.

It is converted into an analog signal by the D/A converter 14 and released as 1'f.
The multiplication by this multiplier circuit 13 that is output is performed using 9 bits of musical tone data 012 as the multiplication output, while modified waveform data D6 and modified envelope data D as the multiplication inputs.
ll is 6 bits and 8 bits, respectively, and if the modified envelope data Dll is small, the modified waveform data D6 is multiplied in such a way that it cannot take a fine value.

Furthermore, the CPUI generates envelope data for a plurality of channels through software processing, and inputs the envelope data to the shift register 16 via the latch 15. Then, the envelope data D9 is given to the noise multiplication circuit 17, noise is added thereto, and the result is given to the multiplication circuit 13 as the modified envelope data D11.
, the converted data D8 is given to the noise generation circuit 18 via the shift register 9, and in this noise generation circuit 18, the noise amplitude level is arbitrarily changed to multiple products, and as a result, the noise data D I O= is applied to the noise multiplication circuit 17, and the noise described in L is added.

The shift registers 3.9, 11.16 take in and cyclically hold data newly output from the latches 2, 8, 10, and 15 at the timing of the corresponding channel, respectively, and hold the data in a circular manner. The data continues to be output until data newer than 15 is output.

Ku noise f! Arithmetic circuit 17. Configuration of Noise Generation Circuit 18> FIG. 3 shows the specific configuration of the noise multiplier circuit 17 and the noise generation circuit 18. In this embodiment, when noise is added, the envelope value is set to any specified value. It is designed to take amplitude values.

That is, a noise source 20 is provided in the noise generation circuit 18, and this noise source 20 outputs a 1-bit noise signal N, which is "1" when noise is added and "O" when it is not added. It is.

This noise signal N is transmitted through five Nant gates 21-5 to 21.
-1 becomes the noise data DIO, which is applied to the noise multiplier circuit 17. Nando game above) 21
-5 to 21-1 are given noise-added signals 085 to 081 of the converted data D8, and the noise signal N is "1".
'', the above noise added signals 085 to D81 are inverted and output, and when rQJ, the noise added signals 085 to D81 are inverted and output.
Regardless of the contents of 81, the maximum level of r3LJ (
Output as decimal representation).

Envelope data D9 from the shift register 16
is 9-bit data (I9-If), which is multiplied by the converted data D10 in a noise multiplier circuit 17 and output as modified envelope data Dll (8-bit representation).

[Operation of Example] Next, the operation of this example will be described with reference to the time chart of FIG.

Now, when the noise addition signals D85 to D81 supplied to the noise generation circuit 18 are being output as rQJ, the output noise data 010 of the Nantes gates 21-5 to 21-1 is always "31", and the noise multiplication The circuit 17 multiplies the envelope data I9 to II, and the result is data D.
ll is further multiplied by the waveform data D5 from the waveform memory 7 in the multiplication circuit 13, and a musical tone is generated and emitted in a noise-free state.Meanwhile, the noise signal N is as shown in FIG. 4(1).
As shown in the figure, if noise is added to the envelope data D9, which is output as "1" or "0" in a random state, for example, the noise added signals D85 to D
If 81 is roolooJ, when the noise signal N is "l", this data ro0100J is inverted from the Nantes gates 21-5 to 21-1 and sent to rtio.
il", that is, the value is "27" in lO decimal notation.

On the other hand, when the noise signal N is "O", the maximum level value is "31" as described above, and FIG. 4 (2) shows this state f.
This shows f4.

FIG. 4(3) shows that the noise added signals D85 to 081 are rl
This shows the state of the data Dll when outputted when the noise signal N is "1" in Fig. 4 at the time of oooOJ.
That is, when the noise signal N is "l", the above data rloo
oOJ is inverted and becomes “01111J,” that is, “15” in io decimal representation, while the noise signal N is “O”
When , the maximum level is "31".

The above is the same even when the noise-added signals D85-D81 take any other value, and when the noise signal N is "1", the noise-added signals 085-D8
The noise data DlO takes a value in which 1 is inverted, and when the noise signal N is 0'', the noise data DlO takes a value of ``31''. Therefore, since the content rate of one noise component is variably controlled according to the magnitude of the noise addition signal 085~])81, it is possible to easily change the content rate of the noise component according to the change of color, etc.

In addition, in the embodiment described in L, the noise signal N is "OJ" or "1".
This data takes the value 11:″”/ ), but it may also be data of 2 or more bits, and this multiple
The additional noise level may be varied by combining the above noise data.

[Effects of the Invention] As described above, according to the present invention, noise is added to the envelope data rather than the waveform data, and at that time, the level of the noise can be variably controlled. Since the envelope data is written to generate and emit envelope-controlled musical tones,
Compared to outputting musical tones by adding noise to waveform data, no bits for noise data are required in the circuit, and for example, data processed by a D/A converter for D-A converting musical tone data. Since the number of bits in 2 is reduced, circuits such as D/A converters can be made smaller and more compact, and the number of bits of data to be processed is also smaller.
Data processing can be performed more quickly, and since the level of noise added to the envelope data is variable, effects such as more natural sound can be obtained.

[Brief explanation of drawings]

Figure i1 is a schematic diagram of the present invention, Figure 2 is an overall circuit diagram of the musical tone generation device, Figure 3 is a specific circuit diagram of the noise generation circuit 18 and noise multiplication circuit 17, and Figure 4 is a diagram of each part of Figure 3. FIG. 1...CPU, 7...Waveform memory, 1
3... Multiplier circuit, 14... D/A converter, 15... Latch, 17... Noise multiplier circuit, 18... Noise generation circuit, 20...
...Noise source, 21-1 to 21-5...Nant gate group, 51...Reading means. 52... Waveform data storage means, 53...
- Noise adding means, 54... Envelope control means, 55... Output means. Figure 3

Claims (1)

[Scope of Claims] Waveform data storage means for storing waveform data, waveform data reading means for reading waveform data from the waveform data storage means, and controlling the envelope of the waveform data read by the waveform data reading means. an envelope data generating means for generating envelope data for the purpose of processing; a noise adding means for adding noise whose amplitude level is arbitrarily changed to the envelope data generated by the envelope data generating means; An envelope control means for controlling the envelope of the waveform data using added envelope data, and an output means for outputting sound according to musical sound data that is envelope-controlled and output from the envelope control means. A musical tone generation device characterized by: