JPS5927916B2 - voice controlled electronic musical instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic musical instrument in which the timbre and effects of musical sounds are controlled by voice.

Traditionally, electronic musical instruments, such as electronic organs, have tablet switches and levers that select the timbre, a lever that changes and selects the composition of harmonics, a lever that changes brilliance that changes the hardness of the timbre, and a lever that turns on/off modulation effects such as vibrato. Various control devices such as switches and volume controls are provided to control depth, speed, etc. Performers performed sophisticated performances by setting and switching these switches, levers, and other operating devices before and during a performance. However, the large number of levers and switches complicates the operation of the electronic musical instrument and also increases the size of the electronic musical instrument. The present invention aims to eliminate such limitations, and allows operating devices such as switches and levers, which were conventionally operated with hands or feet, to be controlled by voice. Hereinafter, the present invention will be explained based on illustrated embodiments. FIG. 1 is a block diagram of one embodiment of the present invention. In Figure 1, the main part 1 of the electronic musical instrument
01 includes a sound source T that generates a scale signal, a keyboard 8 including key switches for selecting a scale signal from the sound source T, a plurality of tone color circuits 9 that add tone to the scale signal selected by the key switch, and the tone color circuit 9. The timbre switch 10 selects a desired musical tone from among the musical tones having a plurality of timbres output by the timbre switch 10, a summing amplifier 11, an output amplifier 12, and a speaker 13.

The microphone 1 converts the performer's voice into an electrical signal.
100 is a feature extractor.

This feature extractor 100 detects features such as pitch frequency, formant frequency, and phoneme of an electrical signal, and outputs different output signals according to the features. In the embodiment shown in FIG. 1, the pitch frequency of the electrical signal is detected and an output corresponding to the pitch frequency is output. 2 is a low-pass filter that extracts the fundamental wave of the electrical signal, 3 is a filter that extracts the zero-crossing wave of the fundamental wave component, 4 is a periodic voltage converter that measures the period of the zero-crossing wave, and 5 is an analog-to-digital converter. It is a converter.

Next, the operation of this embodiment will be explained.

The harmonics of the electrical signal output from microphone 1 are filtered through low-pass filter 2.
, and a fundamental wave that is almost a sine wave is obtained.
Since this signal is sliced at its zero level by the next-stage limiter 3, it becomes a zero-crossing wave having the period of the fundamental wave.
The periodic voltage converter 4 may be one that generates a sawtooth wave voltage having a period of zero crossing waves.Since the peak voltage of this sawtooth wave voltage is proportional to the above period, this peak voltage can be measured using a sample and hold circuit. You can use it to take it out.

The output of the periodic voltage converter 4 is converted into a digital code by an analog-to-digital converter 5. Therefore,
The feature extractor 100 outputs a digital code according to the pitch frequency of the voice. This digital code is decoded by the decoder 6, and the tone switch 10
be selected. For example, when the pitch frequency of #voice is E1-A1, the #1 tone switch is selected, when it is B1-D2, the #2 tone switch is selected, and when the pitch frequency is E2-A2, the #3 tone switch is selected. Power to do? ? Ru.

In this way, by producing a voice with an appropriate pitch, you can select your favorite tone switch. Therefore, there is no need to take your hands off the keyboard during performance, and the same effect as switching a tablet switch at any time can be obtained. The decoder 6 may be something like a read-only memory addressed by the digital code output by the analog-to-digital converter 5. The contents of read-only memory can be set arbitrarily in advance. FIG. 2 is another example of the feature extractor 100. In the figure, a zero-crossing wave having a period of the fundamental wave is obtained by a low-pass filter 2 and a limiter 3, and the period is counted by a counter 23. On the other hand, an envelope detector 20 composed of a rectifier or the like detects the envelope of the electrical signal output from the microphone. The envelope signal is applied to a comparator 21, which provides an output pulse when the envelope signal exceeds a certain level. The output of counter 23 is added to register 22.

While the comparator 21 is outputting an output pulse, the register 22
outputs the output of the counter 23 as it is, but when there is no sound and the output pulse of the comparator 21 disappears, the register 22 enters the storage state.

In this way, the necessary digital code can be outputted from the register 22 by only outputting audio for a short time. Note that the tone switch 10 in FIG. 1 is a MOS type FE switch.
An analog switch using T or the like or a relay can be used.

In addition to the switch provided inside the electronic musical instrument, another switch may be provided in parallel or in series, and this separate switch may be attached to the operation panel of the electronic musical instrument so that it can be operated by hand. In addition, the tone switch 10
It is also possible to make it possible to switch the decoder 6 together with a switch on the operation panel. Also,
The output of the decoder 6 may be applied to the timbre switch 10 via a flip-flop circuit, so that the timbre switch is closed at the first utterance and opened at the second utterance.

In this way, each tone switch can be opened and closed separately, so it is possible to select only one switch or to select multiple switches. In the above embodiment, the tone switch 10 is opened and closed, but other modulation effects such as vibrato, tremolo, etc.
You may open or close the off switch. Further, the depth and speed of the vibrato may be continuously controlled by the analog signal output from the periodic voltage converter 4 shown in FIG. To control the speed of the vibrato, the element constituting the oscillation time constant of the vibrato oscillator, for example, a resistor, may be made of a voltage variable resistor such as an FET. In addition to the modulation effect, the above-mentioned audio characteristics may be used to vary the timbre, volume, pitch and spectrum of the sound source, and the like. Furthermore, in addition to pitch, formant frequencies and phonemes may be used as voice characteristics.

There are many methods already known in the field of speech recognition for extracting such features, and such methods may be used. Furthermore, it is also possible to store not only the characteristics of voices but also their combinations, for example, combinations of pitches of voices, ie, melodies, and control the timbre switch 10 and the like according to the shape of the melodies. A single melody can be stored by temporarily storing the digital code output from the analog-to-digital converter 5 in a storage device. As explained above, the present invention converts voice and vocal cord vibration into electrical signals, extracts the characteristics of the electrical signals, and selects and adjusts the timbre, modulation, and other effects of electronic musical instruments according to the characteristics. This makes it possible to easily adjust and select the effects without using your hands during performance.

Furthermore, it can be expected that there will be fewer restrictions on the arrangement of switches on the operation panel of the electronic musical instrument. Moreover, there is no relationship between the audio signal and the sound source, and each can be treated as independent, so the timbre and modulation effects of the output musical sound can be dynamically controlled in exactly the same way as conventional manual control. Therefore, the function as a keyboard instrument can be made sufficiently excellent.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of an example of a feature extractor used in the present invention. 1...Microphone, 100...Feature extractor, 101...Electronic musical instrument.

Claims (1)

[Claims] 1. A sound source that generates a scale signal, a keyboard that selects a scale signal from the sound source, an operating device that selects or adjusts effects such as timbre and modulation of the scale signal selected by the keyboard, and a sound source that generates a sound or vocal cord vibration. a converter that converts the signal into an electrical signal;
and a feature extractor for extracting features such as pitch frequency, formant frequency, and phoneme of the electrical signal, and the control device is controlled by the output signal of the feature extractor. electronic musical instrument.