JPS58194094A - Sound field spatiality creater - 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] The present invention relates to an electronic musical instrument, and in particular, it is possible to create a feeling of expansion and spatiality of a sound field when an electric signal (instrument sound signal) having no sound field spatial information is reproduced subtly. The purpose of the present invention is to provide a sound field spatiality creation device for an electronic musical instrument that can be used.

Generally, in an electronic musical instrument, the output signal of one or more oscillators is controlled by a keyboard or the like, and the musical instrument signal is obtained through a timbre conversion circuit, and when reproduced through a speaker, the reproduced sound field does not have spatial characteristics. For this purpose, the spatiality creation device shown in Figure 1 (
(commonly called Celeste). In FIG. 1, an electrical signal input to an input terminal 21 is branched into two signals S1, . S2 is obtained, the amplifier is increased by 24.25, and the electronic musical instrument body 2
It is reproduced by the speakers 27 and 28 installed in the 6.

The time delay device 22. '23 is two similar frequency oscillator 29
frequency is about 0.5 Hz, and its two outputs v1. υ
The delay time is controlled by the signal fI*f2 which is converted into a frequency by adding 2 to 2 via the voltage controlled oscillator 30.31. In this case, the player M feels that the musical instrument sound spreads in the area between the two speakers 5P27 and 28.

This principle will be explained with reference to FIGS. 2 to 4. FIG. 2 shows the outputs jTJ of the time delay devices 22 and 23 when the impulse D is input to the input terminal 21.

Showing $2 signal. That is, the Sl or 82 signal is transmitted during the delay time ℃1 to ℃2 from the time T when the impulse D is input, that is, the time ('t2'-"t+)
change. In reality, tl is about 2ms and t2 is 6m.
8, and the change time is about 0.58. FIG. 3 describes the contents of FIG. 2 in more detail, and it can be seen that the Sl signal and the 82 signal change in completely opposite directions between times 12 and 11. FIG. 4 shows the relationship between the changes in the S and 82 signals in FIG. 3 and the sound image direction α perceived by the performer M, under conditions 1.2. of FIGS. 3 and 4.
3 correspond to each other. As shown in Figure 4 [1], the reason why the sound field spreads in the area is mainly because the sound image direction α changes from the center line 0 to the angle 6 at the speaker center with a period of 0.5 seconds. Responsible.

However, the sense of expansion of the sound field due to the spatiality creation circuit used in the above-mentioned electronic musical instrument is fixed between the two speakers 27 and 28 as shown in the areas of FIGS. 1 and 4, Since a time delay device such as a BBD is used, S/
There was a problem with the deterioration of the N ratio.

The present invention eliminates these conventional drawbacks, and is a voltage-controlled amplification means to which an input signal branched into two channels is applied by the output of a two-phase triangular wave generation means that outputs a signal having an opposite phase relationship. The output of the voltage-controlled amplification means is passed through the virtual sound source speaker generation means and applied to the speaker, so that the output of the voltage-controlled amplification means is applied to the speaker to generate the output voltage v1. According to the configuration, the performer can perform You can enjoy high-quality extension to areas outside the speaker that cannot be reproduced.

The present invention will be described below with reference to drawings of embodiments. FIG. 6 shows an embodiment of the present invention, in which 1 is an input terminal, 2.3 is a voltage control amplifier, 4 is a two-phase triangular wave oscillator, 5-digit timing clock pulse generator, 6, A 7-bit, 1-contact, 4-circuit analog switch, such as the 2-bit control multiplexer L] μI) D manufactured by Hondenki (2))
40669)N. 8 and 9 are virtual sound source generation circuits, 10 and 11i: 7 amplifiers, 12 and 13i (↓ speakers).

The signal input to input terminal 1 is branched into two to obtain signal 51S2 via voltage control amplifier 2.3, and outputs O4 to 04 and outputs 05 to 08 are obtained by analog switch 6.7 with 4 circuits per contact. After that, outputs 01 and 05, outputs 02 and 06. By adding outputs O1 and 07 + outputs 04 and 08, respectively, ":" output OI + "2 + "3
+ "4" is generated.Next, the output 6102 is directly added without any intervention, and the output "3 + "4 is added via virtual sound source generation circuits 8 and 9, which will be described later, and then output δ5.
66, speaker 12.1 through amplifier 10.11
Play on 3. The voltage distribution control amplifiers 2 and 3 are controlled by a triangular wave oscillator 4, and the triangular wave oscillator 4 and analog switch 6 are controlled by the output P of a timing clock pulse generator 5.

FIG. 6 shows a timing diagram of the P, S, S, . . . 01 to 08 signals. The pulse of Pl is output from the generator 5, thereby triggering the triangular wave oscillator 4 and the analog switch 6.7. For example, pulse p.

When the output S] of the voltage control amplifier 2 is inputted, the level of the output S of the voltage control amplifier 2 becomes small, and the output S2 of the voltage control amplifier 3 becomes large, so that the level difference between the two channels changes. And the analog switch 6.7 has an output of 1: OI and 06.
By turning ON the sound image, the sound image moves from the supino 712 to the speaker 13 in the area shown in FIG. Then P
When 2 is input, only outputs 02 and 07 are turned on and the area ■
The sound image moves from the speaker 13 to the speaker 14. In other words, by controlling the real sister example shown in Fig. 5 as shown in Fig. 6, the sound image can be moved including the lateral direction, and by controlling at a period of about 0.6 degrees, the sound field can be moved laterally. It can be expanded in any direction.

Methods for controlling the sound image direction localization include a method of changing the level difference between two channels and a method of changing the time difference between the two channels. In this embodiment, the method is based on the former method of changing the level difference. In FIG. 7, the signal input to input terminal 1 is
It is branched into two and passed through voltage control amplifiers 2 and 3 respectively to obtain output signals S, S2, amplifiers 10 and 11 and speaker 1.
It will be played on 2.13. The voltage controlled amplifier 2.3 is
The triangular wave signals e, , which are in an anti-phase relationship with each other shown in Fig. 8,
/! A two-phase 3. It is controlled by a square wave oscillator 4. That is, if the sound image direction α perceived by the performer M in FIG. 7 is -1 in the area 1 in FIG.
2 to the speaker 13, that is, from right to left. In other words, it is the same as the change from condition 1 to condition 3 shown in FIG. This method does not use a time delay device, so a high S/N ratio can be achieved.

In addition, as a method of expanding the sound field sense region as described above to the side of the performer M by the reproduction by the speakers 12 and 13, a virtual sound source speaker is created at 90 degrees to the side of the performer M. This can be realized by changing the level difference not only between the real sound source speakers 12 and 13, but also between the real sound source and the virtual sound source speakers, or between the virtual sound source speakers.

Next, the above-mentioned virtual sound source speaker generation circuit will be explained based on FIG. 9. In the figure, 17 is a binaural common circuit, and 18 is a binaural difference generating circuit, and these two circuits form the virtual sound source speaker generating circuit 9 or 8. In this figure, H1+ and HI3 are the transfer functions between the speakers sp, , sp, and the left and right ears of listener M, and Hφ1 and Hφ2 are the transfer functions placed 90' to the left of listener M. It is a transfer function between the SP3 and the listener's left ear and right ear. If the sound pressure given to the left and right ears of listener M by applying signals to speakers SP1 and SF3 is the same as the sound pressure given by speaker SP3 placed 90' to the left of the listener, then listener M It feels like only speaker SP3 is placed there. In order to create such a phenomenon, a binaural common circuit 1 and a binaural difference generating circuit 18 are connected before the left and right speakers sp, sp2, and the characteristics of the binaural common circuit 17 are Hφ+/H++. Also, the characteristics of the binaural difference generation circuit 18 are (H11Hφ2HI2Hφ+)/(H11Hφj H
j2Hφ2).

When such a virtual sound source speaker generation circuit is used, listener U listens to the sound radiated from speakers SP, , SF3 as if speaker SP is located 90' to the left of listener M.
3 is placed, and it feels like you are listening to the sound that is being radiated. That is, a virtual sound source speaker SP3 is created in the direction 900 to the left of the listener.

As described in detail above, according to the present invention, the performer can enjoy the expansion of the product to areas outside the speaker, which is the actual sound source. Furthermore, since the sound image direction localization is controlled based on the method of changing the level difference between two channels, it has the advantage of not requiring a time delay device such as a5D and achieving a high S/N ratio.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a spatiality creating device used in a conventional electronic musical instrument, FIGS. 2, 3, and 4 are conceptual diagrams of the same device, and FIG. 6 is a block diagram of an electronic musical instrument according to the present invention. A block diagram showing an embodiment, FIG. 6 is a timing diagram of the same instrument, FIG. 7 is a block diagram of a sound image direction localization control circuit of the same instrument, and FIG. 8 is an output of a 10-phase two-phase triangular wave oscillator used in the same circuit. The waveform diagram and FIG. 9 are block diagrams of the virtual sound source speaker generation circuit of the musical instrument. 2.3... Voltage control amplifier, 4... Two-phase triangular wave oscillator, 5... Lock pulse generator for quising, 6.7... Analog switch, 8 .9
..., ... Imaginary sound source speaker generation circuit, 10.11 ・
°...Amplifier, 12.13... ・Speaker. Name of agent: Patent attorney Toshio Nakao and 1 other person @
2 Figure! Figure 3 Figure 4 Figure 6 Direction □ Figure 7 Figure 8

Claims (1)

[Claims] branching means for branching an input signal into two channels; two-phase triangular wave generation means for outputting a signal of opposite phase; and voltage control amplification means controlled by the output of the triangular wave generation means;
a switching means for selecting one of the four channel outputs as a channel input; a virtual sound source speaker generating means for creating a virtual sound source speaker on the side of the performer; - the triangular wave generating means and the switching means. 1. A sound field spatiality creating device comprising a clock pulse generation means for timing control.