JPH0748917B2 - Sound field correction system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound field correction system that performs sound reproduction using a speaker system.

2. Description of the Related Art Conventionally, as a method for correcting acoustic characteristics, most of the methods have been to measure actual acoustic characteristics, calculate a correction value based on the measured value, and set the correction value in a correction device.

Hereinafter, the sound field correction system described above will be described with reference to the drawings.

FIG. 3 shows the configuration of a conventional sound field correction system. In FIG. 3, 1 is an input unit, 3a to 3c are correction devices, 4a to 4c are amplifiers, 5a to 5c are speakers, 6 is a microphone, 7 is an acoustic characteristic measuring instrument, 8 is a correction characteristic calculating means, 9
Is a control means.

With respect to the sound field correction system configured as described above, its acoustic characteristic correction method will be described below.

First, the input unit 1 is used to measure the acoustic characteristics of the reproduction location.
A signal for acoustic characteristic measurement is added to. Pink noise or impulse is mainly used as the measurement signal.

The measurement signal input from the input unit 1 is corrected to an arbitrary frequency characteristic by the correction devices 3a to 3c, amplified by the amplifiers 4a to 4c, and reproduced from the speakers 5a to 5c. The reproduced signal that has entered the microphone 6 is analyzed by the acoustic characteristic measuring device 7 to obtain the sound pressure frequency characteristic. The correction characteristic calculation means 8 calculates the correction characteristic based on the obtained sound pressure frequency characteristic so that the characteristic at the position of the microphone 6 becomes flat or desired. The control means 9 sets the obtained correction characteristics in the correction devices 3a to 3c. Here, an equalizer is used for the correction devices 3a to 3c. By repeating the above operation several times, it is possible to listen with a flat or desired frequency characteristic at the listening position.

Problems to be Solved by the Invention However, in the above-mentioned configuration, in the case where the number of speakers is increased, a number of correction devices are adjusted, or in a place where the reproduced sound field is wide, a lot of places are required. Therefore, there is a disadvantage that the acoustic characteristics have to be measured at, and that it takes a very long time to adjust the acoustic characteristics.

In view of the above problems, the present invention uses all reproduction locations and a plurality of speakers by calculating and predicting the acoustic characteristics of the reproduction location in advance by the acoustic characteristic calculation means and setting the correction characteristics in the correction device of each speaker. Even in the case of doing so, it is intended to provide a sound reproduction system capable of efficiently adjusting the sound characteristics.

Means for Solving the Problems In order to achieve the above object, the sound field correction system of the present invention calculates an input device for inputting a shape of a reproduction place and acoustic characteristics of the reproduction place input from the input device. Acoustic characteristic calculation means, a display for displaying the shape of the reproduction place and the calculation result, an acoustic characteristic measuring instrument for actually measuring the acoustic characteristic of the listening position, and the acoustic characteristic calculation obtained by the acoustic characteristic calculation means. A correction characteristic calculation means for calculating a correction characteristic from the result and the result of the acoustic characteristic obtained by the acoustic characteristic measuring device, and a delay for making the time for the sound emitted from a plurality of speakers to reach the listening position constant. And a correction device for correcting the acoustic characteristics of the speaker, and a control means for setting a state based on the correction characteristics. The correction characteristics calculation means calculates the correction characteristics, and the correction characteristics are calculated according to the correction characteristics. It is characterized in that the operation for setting the state is repeatedly performed by the control means.

Effect The present invention calculates the acoustic characteristics of the reproduced sound field by the above-described configuration and automatically sets the correction characteristics in the correction device of each speaker in advance. Therefore, compared with the case where only the measurement is performed, all reproduction locations, and Even when a large number of speakers are used, the acoustic characteristics can be adjusted efficiently and in a short time.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a sound field correction system in an embodiment of the present invention.

In FIG. 1, 1 is an input unit, 2a to 2c are speakers 5a to 5c.
And a delay device for adjusting the time between the microphones 6a to 6b, 3a to 3c are correction devices for correcting acoustic characteristics, 7 is an acoustic characteristic measuring instrument for measuring and analyzing acoustic characteristics, and 8 is an acoustic characteristic measuring instrument 7. Correction characteristic calculation means for calculating values to be set in the delay devices 2a to 2c and the correction devices 3a to 3c based on the measured characteristics, 9
Is the delay values 2a to 2c based on the correction value obtained by the correction characteristic calculating means 8.
And control means for setting the correction devices 3a to 3c, 10 is an input device 11
An acoustic characteristic calculation means for calculating the sound pressure frequency characteristic of the reproduction place input from the reference numeral 12 is a display for displaying the result of the acoustic characteristic and the shape of the reproduction place.

The operation of the sound field correction system configured as described above will be described below.

First, the shape of the place where the audio signal is reproduced from the input device 11,
Input the speaker position / direction, listening position, etc. The input device 11 can be composed of a keyboard, a mouse, a digitizer, and the like. The input shape is displayed on the display 12. Next, the acoustic characteristic calculation means 10 obtains the sound pressure frequency characteristic at the listening position, the reverberation time, the sound pressure distribution characteristic at the reproduction place, the microphone-speaker distance, and the like. FIG. 2 shows the sound pressure distribution characteristic of the floor surface of the reproduction place. In FIG.
The level of sound pressure level is shown by the iso-sound pressure line. In this embodiment, as a method for obtaining the acoustic characteristic and the sound pressure distribution characteristic, a method for obtaining the reflection path passing through the listening position and the sound source and calculating the sound pressure is used. Further, the sound absorption coefficient of the wall surface of the reproduction place and the directivity of the speaker which are used for the calculation are inputted in advance.

The correction characteristic calculation means 8 calculates the delay time of the delay devices 2a to 2c and the correction values of the correction devices 3a to 3c on the basis of the acoustic characteristics and the microphone-speaker distance obtained by the acoustic characteristic calculation means 10. Here, an equalizer is used as the correction devices 3a to 3c. The control means 9 sets the delay time obtained by the correction characteristic calculation means 8 and the correction value of the acoustic characteristic in the delay devices 2a to 2c and the correction devices 3a to 3c.

Next, a signal for acoustic characteristic measurement is applied to the input unit 1 in order to measure the acoustic characteristic of the reproduction place. The measurement signal input from the input unit 1 is delayed by the delay devices 2a to 2c, and corrected by the correction devices 3a to 3c to have the frequency characteristics obtained above,
It is reproduced from the speakers 5a to 5c. The reproduced signals that have entered the microphones 6a to 6c are analyzed by the acoustic characteristic measuring device 7 to obtain the sound pressure frequency characteristic. In the correction characteristic calculation means 8, the microphones 6a to 6c are based on the sound pressure frequency characteristics thus obtained.
The correction characteristics are calculated so that the characteristics at the position of are flat or have desired characteristics. The control means 9 sets the obtained correction characteristics in the correction devices 3a to 3c again. The sound pressure frequency characteristic is measured by the acoustic characteristic measuring device 7 as described above, the correction characteristic is calculated by the correction characteristic calculating means 8, and the correction characteristics are corrected by the correction devices 3a to 3c.
By repeating the operation of setting to, several times, it is possible to hear a flat or desired frequency characteristic at the listening position.

As described above, according to the present embodiment, it is possible to accurately adjust the acoustic characteristics in a short time by calculating the acoustic characteristics of the reproduction place in advance and then measuring the acoustic characteristics and performing fine correction. .

In this embodiment, the delay device and the correction device are used for correction, but the same effect can be expected with only one of the corrections.

Further, a sufficient correction effect can be obtained even if fine adjustments due to the measurement of acoustic characteristics are omitted.

EFFECTS OF THE INVENTION As described above, the present invention is configured to calculate the acoustic characteristics of the reproduced sound field and automatically set the correction characteristics in the correction device of each speaker in advance. Even when reproducing using, it is possible to easily adjust to desired acoustic characteristics in a short time.

[Brief description of drawings]

FIG. 1 is a block diagram of a sound field correction system according to an embodiment of the present invention, FIG. 2 is a sound pressure distribution characteristic diagram obtained by an acoustic characteristic calculation means, and FIG. 3 is a block diagram of a conventional sound field correction system. Is. 1 ... Input part, 2a-2c ... Delay device, 3a-3c ... Correction device, 7 ... Acoustic characteristic measuring device, 8 ... Correction characteristic calculation means,
9 ... Control means, 10 ... Acoustic characteristic calculation means, 11 ... Input device, 12 ... Display device.

Claims (1)

[Claims] 1. An input device for inputting a shape of a reproduction place, an acoustic characteristic calculation means for calculating acoustic characteristics of the reproduction place input from the input device, and a display for displaying the shape of the reproduction place and a calculation result. And an acoustic characteristic measuring device for actually measuring the acoustic characteristic of the listening position, and a correction characteristic from the acoustic characteristic calculation result obtained by the acoustic characteristic calculating means and the acoustic characteristic result obtained by the acoustic characteristic measuring device. Based on the correction characteristics, a correction characteristic calculation means for calculating, a delay device for making a time for a sound emitted from a plurality of speakers to reach a listening position constant, and a correction device for correcting the acoustic characteristics of the speakers are calculated. A sound field comprising: a control means for setting a state, and a correction characteristic calculation means for calculating a correction characteristic, and the control means repeatedly setting a state according to the correction characteristic. Positive system.