JPS61273592A - Sound source unit for electronic musical instrument - 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 invention] The present invention relates to a sound source device for an electronic musical instrument.

[Prior art and its problems]

Conventionally, predetermined waveform information has been stored in a waveform memory and read out at a speed corresponding to the musical scale to obtain waveform information of musical tones.

By the way, Japanese Patent Laid-Open No. 54-61511 discloses a technique in which, for example, sine wave information is stored in a waveform memory, and this sine wave information is changed as appropriate and read out as different waveform information.

According to this conventional technology, the step speed of the address signal for accessing the waveform memory is switched in the middle of the waveform period, and for this purpose, different frequency information is transferred from the frequency information memory within the waveform period. It must be switched with and applied to the address counter.

Therefore, there is a problem in that frequency information must be appropriately set in the frequency information memory in advance, and that it is not easy to perform many types of waveform shape conversions.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a sound source device for an electronic musical instrument that can easily obtain musical sound waveforms having various shapes from a waveform memory.

[Key points of the invention]

The present invention non-linearly transforms the address signal generated by the address signal generating means to the waveform memory means by the non-linear transformation memory means and provides an f-transformed address signal, thereby easily generating musical sound waveforms of various shapes. It is made possible to occur.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows its configuration, and reference numeral 1 denotes a keyboard, which has a plurality of playing keys for each scale.

The key assigner 2 sends a key scan signal to the keyboard l, converts the resulting key operation signal into a key code, and stores it in the key code register 3 of one of the eight channels, for example.

The key code register 3 sends the stored key code to the frequency memory 4, for example, in a time-division manner.

The frequency memory 4 stores frequency information corresponding to each scale, and eight channels of frequency ↑fl information are output in a time-division manner. In the drawings, this frequency information is indicated as F.

Then, this frequency information F (well, it is supplied to the accumulator 5 which performs the accumulation operation according to the clock of a predetermined frequency, and becomes the accumulation information -f-F. This accumulator 5 also functions as the above-mentioned key code register 3. Similarly, time division processing for 8 channels is performed.

The output of this accumulator 5 is then supplied to a nonlinear conversion filter AM6. Waveform information from a waveform information input device such as a digitizer 7 is written into the nonlinear conversion AM 6 under the control of the nonlinear conversion RAM control section 8.

That is, the nonlinear conversion RAM control unit 8
Its operation is defined by the control signal of U, and while giving an address signal to the address input terminal AD of R and AM6 for nonlinear conversion, waveform information is supplied to the data input/output terminal DATA, and a write signal νm is sent out. Then, the waveform information inputted by the performer's operation on the digitizer 7 is set prior to the performance.

The address input terminal 21 of this nonlinear conversion R, AM 6 is supplied with the output #F (i.e. address signal) of the accumulator 5 when its contents are read, and the waveform stored from the data input/output terminal DAT is supplied. Information is read. At this time, the readout signal ~ is applied to the nonlinear conversion filter AM6.

The information outputted from the nonlinear conversion RAM 6 (that is, the conversion address signal) is given to a waveform memory (in which waveform information of a sine wave is stored, for example).
The waveform information is time-divisionally output for 8 channels.

The output of this waveform memory 9 is supplied to a multiplier 1o, and an envelope control circuit 1 which outputs envelope information for eight channels in a time-sharing manner under the control of a key assigner 2.
The operation of this embodiment will now be described.

First, the performer uses the digitizer 7 to set desired waveform information in the nonlinear conversion AM 5 prior to playing. For example, as shown in the left column of (A) in Figure 2, from O to 2π
Draw a straight line using the range concave. Therefore, corresponding to that straight line, 0
We get an output of 2π from .

In this case, one key operation is performed on keyboard 1,
The frequency information F corresponding to that scale is 7 cumulators 5
The address signal (then, the address (No. 1 (=t-F)) is directly output (without any conversion).

Therefore, the waveform memory 9 outputs the stored waveform information, that is, waveform information representing a sine wave, as shown in the right column of No. 21 & (A).

Similarly, when inputting the polygonal line shown on the left PIAVc in tg2 diagram (B), exactly 3/4π is input as the address signal (Z F
), the address advancement speed changes. That is, in that case, the waveform will be distorted and output as shown in the right column of FIG. 2(B).

Similarly,! When the waveform information is set from the digitizer 7 to the nonlinear conversion ratio AM6 as shown in the left column of Figure 2 (C), the waveform information shown in the right column is output from the waveform memory 9 @ Also, to the nonlinear conversion ratio AM6, Sine wave (y=π+π5
inx), the same! ffl As shown in (D), the waveform (y==i
Bi(1(π+5lnx)) is obtained.

As described above, when the performer inputs an arbitrary waveform to the nonlinear conversion ratio A M 6 in the digitizer 7, the original address signal is nonlinearly converted according to this waveform, a converted address signal is obtained, and this conversion Since the waveform memory 9 is accessed based on the address signal, any waveform different from the original waveform can be obtained, making it possible to easily generate musical tones of various tones.

In the above embodiment, the player inputs the desired waveform using the digitizer 7, but various character/graphic input devices may be used. For example, it is possible to link a computer such as a personal computer with an electronic musical instrument, and use the input device of the computer to set waveform information to the nonlinear conversion RAM 5.

Further, writing the waveform information to the nonlinear conversion RAM 64C may be performed by the CPU depending on the tone color selection.

That is, the CPU may store a plurality of waveform patterns in advance and selectively write them into the nonlinear conversion ordinary person M6.

〔Effect of the invention〕

As described in detail above, the present invention non-linearly transforms the address signal generated by the address signal generating means using the memory means for non-linear transformation that can be written, and accesses the waveform memory means according to the obtained converted address signal. This has the advantage that various waveforms can be obtained extremely easily, and musical tones of various tones can be easily generated.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a circuit tank rl; & FIG. 2 is a waveform diagram for explaining its operating state. 4...Frequency memory, 5...Accumulator, 6...Nonlinear conversion RAM. 7... Digitizer, 9... Waveform memory.

Claims (1)

[Scope of Claims] Waveform memory means for storing predetermined waveform information; address signal generation means for generating address signals at a speed corresponding to the frequency of musical tones to be generated; memory means for nonlinear conversion; a writing means for writing desired waveform information into the memory means for non-linear conversion; and a writing means for writing desired waveform information into the memory means for non-linear conversion; A sound source device for an electronic musical instrument, comprising means for converting the predetermined waveform information using the converted address signal and supplying the converted address signal to the waveform memory means, and accessing the predetermined waveform information using the converted address signal.