JP2001147693A - Method of correcting reproduced output in sound reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a correction method of reproduced output which approximates reproduced sounds to the state of actual sounds without requiring a complicated work like equalizer adjustment. SOLUTION: When a sound reproducing device is installed in a prescribed place, a target reproducing level of floor impact sound data is set to an average value Lk of floor impact sound levels preliminarily measured at intervals of a center frequency fk, and impact sound data converted into a digital signal is reproduced to emit sound in the installation space by a speaker 4, and reproduced sound are picked up by a microphone 6. Thereafter, the acoustic pressure level of the reproduced output in each frequency band is measured, and the deviation from the target reproducing level is calculated, and a digital filter to cancel the deviation is prepared, and data obtained by filtering impact sound data by this digital filter is taken as sound source signal data in the installation place.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting a reproduction output level of a sound reproducing device used for an environmental sensation device for reproducing and experiencing environmental sounds in an apartment house such as a building or an apartment. is there.

[0002]

2. Description of the Related Art In recent years, when a detached house or an apartment house such as a building or an apartment is constructed, the sound of an adjacent room is leaked or the floor sound of a room on an upper floor is not leaked to a lower floor. The design, material and structure are selected in consideration of the sound insulation performance. In order to evaluate the sound insulation performance of such rooms, when a house is built, when measuring the sound pressure level between rooms to measure the sound pressure level of sound leaking between adjacent rooms, or from the upper floor to the lower floor 2. Description of the Related Art A floor impact sound level is measured to measure a floor impact sound level leaking to a floor. In addition, when selling a house to a customer, an environment sensation device for reproducing the sound of floor impact of the room in the house recorded in advance in a model room or the like so that the user can experience the sound insulation performance and the like of the house. Development is active. Such an environment sensation device is capable of transmitting a sound (sound source signal) such as a recorded or created floor impact sound.
The sound is reproduced by a sound reproduction device in a bodily sensation room equipped with a speaker, so that a bodily sensation can be experienced by the sound. The above experience room is
Usually, a sound insulation device is provided so that noise from the outside does not propagate, and the environment is such that the sensible person can fully experience the sound.

The frequency characteristics of the reproduced sound may be different from those of the original sound due to, for example, the non-linearity of the frequency characteristics of the loudspeaker and the difference in the sound field due to the members used in the bodily sensation room and the structure of the space. is there. Therefore, in the sensation room, the reproduced sound is not always faithful to the actual sound. Therefore, usually, an equalizer is provided between the sound reproducing circuit and the amplifier to change the frequency characteristic of the reproduced sound, thereby correcting the reproduced sound to be faithful to the sound source signal. Specifically, a test signal having a preset frequency characteristic is generated from a speaker, the reproduced sound is sampled by a microphone, frequency analysis is performed, and the equalizer is adjusted so that the frequency characteristic of the reproduced sound becomes flat. .

[0004]

However, the adjustment of the equalizer is usually performed manually, which is not only inefficient, but also requires changing the gain of a specific band.
Since this change affects the gain of other bands, it is said that several times of correction work is necessary even for a worker with some experience, and if the worker is not a skilled person, a considerable amount of adjustment is required. In addition to taking a long time, there is a problem that it is difficult to give the reproduced sound a characteristic based on the indoor environmental characteristics.

The present invention has been made in view of the conventional problems, and does not require complicated operations such as equalizer adjustment and the like, and provides the reproduced sound with characteristics based on the environmental characteristics of the room, thereby realizing the actual sound. It is an object of the present invention to provide a reproduction output correction method that can approximate a sound-like state.

[0006]

According to a first aspect of the present invention, there is provided a method of correcting a reproduction output in a sound reproducing apparatus, wherein a target reproduction level of a reproduction output is set in a plurality of predetermined frequency bands, and a digital signal is reproduced. Reproduce the sound source signal data converted into a signal, measure the level of the reproduction output in each of the frequency bands, calculate the deviation from the target reproduction level, and then pass through each frequency band to cancel the deviation. A digital filter having a gain is created, and data obtained by filtering the sound source signal data by the digital filter is used as sound source signal data at the installation location of the sound reproducing device.

According to a second aspect of the present invention, there is provided a method of correcting a reproduction output in a sound reproducing apparatus, wherein a maximum correction amount of each time of the digital filter is regulated and a sound pressure level of the reproduction output is corrected a plurality of times. It is characterized by having done.

According to a third aspect of the present invention, there is provided a method for correcting a reproduction output in a sound reproducing apparatus, wherein the sound source signal data is converted into a sound pressure signal of an impact sound generated in a predetermined sound source room and a sound is received on a lower floor of the sound source room. After sampling in the room and A / D converting the collected sound pressure signal, using the A / D-converted quantized data, a plurality of preset frequencies are respectively set as center frequencies. In addition to the floor impact sound data when the floor impact sound level is measured, the target reproduction level is a floor impact sound level in each of the calculated frequency bands.

According to a fourth aspect of the present invention, there is provided a method for correcting a reproduction output in a sound reproducing apparatus, wherein the sound source signal data is converted into a sound pressure signal of a noise generated in a predetermined sound source room in a sound receiving room adjacent to the sound source room. A / D conversion is performed on the sampled sound pressure signal, and the A / D converted quantized data is used to set a sound pressure in a frequency band having a plurality of preset frequencies as center frequencies. Calculate the level, and with the sound pressure data in the sound receiving room when the room sound pressure level difference between the sound source room and the sound receiving room is obtained, and set the target reproduction level in each of the calculated frequency bands. The sound pressure level.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an outline of an automatic output adjustment system of a reproduction output in a sound reproducing device according to the present embodiment, FIG. 2 is a flowchart showing a method of correcting the reproduction output, and FIG. 3 is a diagram showing a correction state of the reproduction output. is there. Hereinafter, the reproduced sound is the floor impact sound in an apartment house,
A method of correcting the reproduction output of the sound reproducing device of the floor impact sound sensation device will be described. First, a method of measuring the floor impact sound level will be described. When measuring the level of the floor impact sound leaking from the upper floor room to the lower floor, as shown in FIG. 4, the floor impact sound installed in the sound source room A, which is the upper floor room, is struck by the floor. Light impact source, consisting of a hammer for generating
Alternatively, a floor impact sound is generated at a plurality of places by a floor impact sound generator 10 which is a single heavy impact source for generating a floor impact sound by being dropped on a floor such as an automobile tire. The impulsive sound propagated into the sound receiving room B via the measurement target floor (including the ceiling of the sound receiving room B, which is a lower floor room) C directly below the sound source room A is collected, and From the collected sound pressure signal, the sound pressure level arithmetic unit 20 extracts a sound pressure signal whose band is limited for each of a plurality of preset frequencies, and extracts the sound for each of the frequencies from the extracted sound pressure signal. The floor pressure sound level is obtained by calculating the pressure level. As the measurement frequency band, for example, f ₁ = 63 Hz is a basic frequency, and seven types of frequencies (f ₁ = 63 Hz,
f ₂ = 125 Hz, f ₃ = 250 Hz, f ₄ = 500 Hz, f ₅ = 1000 Hz,
(f ₆ = 2000 Hz, f ₇ = 4000 Hz) is measured for each center frequency in the frequency band of 1 octave width with each center frequency. Further, in the sound source room A, for example, floor impact sounds are generated at five impact points A _{1 to} A _{5 in} the same figure, and in the sound receiving room B, respectively, at five points B _{1 to} B _{5 in} the same figure. The floor impact sound is measured. The frequency band is 1
The same applies to / 3, 1/12, etc.

In the sound pressure level calculating device 20, a micro
Impact point A collected by phone 15_i, Measurement point B_jSound pressure signal
Is amplified by the low-noise amplifier 21 and then sent to the A / D converter 22.
Here, for example, the sampling frequency F_S0At 44.1kHz
Sampling and quantization, quantized data (sound pressure
Data) is stored in the RAM 23. Next, set the frequency
In stage 24, the center frequency is_k= 4kHz
In both cases, the sound pressure data at a predetermined measurement location is stored in the RAM 23
From the center frequency above one octave band
Limit value f_c1Digital low-pass filter with cut-off frequency
25 and filtered. Furthermore, the filter
1% of the center frequency
Cut-off frequency f_c2Digital Ha
Filtered by the pass filter 26, the center frequency
Number f_k= Audio data of one octave band at 4kHz
Extract. Next, the sound pressure level calculating means 27
Square-averaging the sound pressure data with the band
Pressure data size L_ijk(I: impact point, j: measurement point,
k; frequency). Measurement of floor impact sound level
Is the data L_ijkFrom the measurement point B₁~ B_FiveFloor impact at
Average sound level L_ikIs calculated by the following formula, and L_ik= (1 / n) Σ10^{(Lijk / 10)}  Further, the average value L of the floor impact sound level_ikFrom the following formula
Each frequency band (center frequency f_k) Average value L_kCalculate
You. L_k= (1 / m)） L_jk Finally, the horizontal axis represents the frequency and the vertical axis represents the floor impact.
Sound level, and floor impact sound level for each center frequency
The floor impact sound level is measured using a straight line graph.
Complete.

Next, an automatic output adjustment system for reproduction output will be described. In FIG. 1, reference numeral 1 denotes a reproduction waveform correction device for correcting a reproduction waveform, a personal computer provided with a reproduction waveform correction program, and 2 a floor impact sound data stored in the personal computer 1 (stored in the RAM 23). A sound card for reproduction for D / A conversion of sound pressure data), an amplifier 3 for amplifying a floor impact sound signal from the sound card 2 for reproduction, and a floor impact sensor 4 installed near the ceiling above the sensation room 5 A speaker that generates sound, 6 is a microphone that collects floor impact sounds in the sensation room 5, and 7 is a sound card for detection that performs A / D conversion of the floor impact sounds collected by the microphone 6. The personal computer 1 stores the floor impact sound data (sound source data) which is a reproduction sound and data of the floor impact sound data of, for example, 1/3 or 1/1 target octave band level (target reproduction level; The average value L _k of the floor impact sound level for each center frequency f _k ) and the maximum change value of the correction level per time, which is the correction data condition;
The maximum change value of the correction level in Total, the data of the allowable range of the deviation (hereinafter referred to as an error) between the sound source data collected by the microphone 6 and the target reproduction level, which are the correction end conditions (all in dB), and A setting program is loaded in advance.

Next, a method of correcting the reproduction output of the floor impact sound level will be described with reference to the flowchart of FIG. First, the total correction data is initialized to 0 (initial setting; step S1). Next, the captured floor impact sound data is read out (step S2), D / A converted and amplified, and a floor impact sound, which is a reproduction sound, is generated from the speaker 4 in the sensation room 5, The floor impact sound is collected by the microphone 6, and the collected floor impact sound data is A / D converted and stored (step S).
3). Then, from this A / D converted data, 1/3
Alternatively, data of the 1/1 octave band level (floor impact sound level) is calculated (step S4). Next, the calculated floor impact sound level is compared with the data of the target octave band level, and a required correction amount (error) in each octave band as correction data is calculated (step S5). It is determined whether or not the error is within a preset allowable range (step S6). FIG.
(A) to (c) are diagrams showing the correction status of the reproduction output by the correction method of the present invention. The horizontal axis is the measurement frequency, and the vertical axis is the measured sound pressure level data (the left is the L value of the sound pressure level). The solid line indicates the frequency characteristic of the floor impact sound data collected by the microphone 6, and the broken line indicates the target level for each octave band. If the error is within the allowable range, as shown in FIG. 3C, it is determined that correction has been completed (if it is the first time, no correction is necessary) and the data is saved (step S7). . In step S6, if the number of corrections exceeds the preset maximum number of updates,
The process proceeds to step S7 without any further correction, and the correction operation is completed.

In step S6, as shown in FIG. 3 (a), when the error is outside the allowable range, within each octave band, within the preset maximum change value per time, and Within the maximum change value in Total, the total correction data for adjusting the reproduction output is determined (step S8), and based on the total correction data,
A folding correction filter for changing the frequency characteristics of the floor impact sound data for reproduction is created (step S9).
Thereafter, the floor impact sound data for reproduction is filtered using the correction filter to update the floor impact sound data (step S10). Then, returning to step S3, the updated floor impact sound data is used as new sound source data, which is D / A converted and generated as a floor impact sound from the speaker 4 in the sensation room 5, and this floor impact sound is also generated. Is collected by the microphone 6, and the collected floor impact sound data is A / D converted and stored. Thereafter, a floor impact sound level is calculated in step S4, an error in each octave band is calculated in step S5, and the error is determined in step S6. As a result, if the error is within the allowable range as shown in FIG. 3C, it is determined that the correction has been completed, the process proceeds to step S7, and the data is stored. On the other hand, as shown in FIG. 3B, if the update count is within the maximum update count and the error is still beyond the allowable range, a folding correction filter is created again (step S).
9) The floor impact sound data is corrected by repeating the operation of updating the floor impact sound data using the correction filter (step S10). When the correction operation is completed, in step S7, the characteristic data of the correction filter finally used and the corrected floor impact sound data for reproduction (D / A data) are stored. .

As described above, according to the present embodiment, when the sound reproducing device of the floor impact sound sensation device is installed at a predetermined place, the personal computer 1, which is a reproduction waveform correction device, outputs the floor impact sound data. the target reproduction level, with the previously measured center frequency is set to the average value L _k of the floor impact sound level for each f _k, by reproducing the converted impulsive sound data into digital signals to the installation space in the speaker 4 The sound is generated and the reproduced sound is collected by the microphone 6. Then, after measuring the sound pressure level of the reproduction output in each of the frequency bands and calculating a deviation from the target reproduction level, a digital filter that cancels the deviation is created, and the impulsive sound data is converted into the digital signal. Data filtered by the filter,
Since the sound source signal data at the installation location is used, a complicated operation such as adjustment of an equalizer is not required, and the floor impact sound as a reproduced sound can be automatically adjusted and output to a state close to the actual state.

In the above embodiment, the case where the sound to be reproduced is a floor impact sound in an apartment house has been described. However, the reproduced sound is not limited to this, and a reference target level is set. Sound source signal data. For example, when sound leakage from an adjacent room is used as a reproduced sound, measurement data of an inter-room sound pressure level and a sound source sound pressure level, which measures the sound pressure level between adjacent rooms, is used. I just need. As shown in FIG. 5, the measurement of the inter-room sound pressure level is performed by generating a wide-band noise that generates white noise including a plurality of frequencies f _{1 to} f ₆ used in the measurement of the sound pressure level in the sound source room A. A noise (white noise) is generated from a sound source device 10A including the sound source 1, the power amplifier 2, and the speaker 3, and the microphone 15A is moved along a predetermined route in the sound source room A and the sound receiving room B. , And continuously at approximately the same speed for 10 to 30 seconds to collect sound pressure signals in the sound source room A and the sound receiving room B, and calculate the sound pressure level in the sound pressure level calculation device 20A. The sound pressure level computing device 20A used for measuring the inter-room sound pressure level has substantially the same configuration as the sound pressure level computing device 20 used for measuring and measuring the floor impact sound. The sound pressure level calculating means 27 is provided at the subsequent stage with a sound pressure level difference calculating means 28 for calculating the inter-room sound pressure level difference between the sound source room A and the sound receiving room B. Therefore, a detailed description of the operation is omitted.
In addition, the automatic output adjustment system of the reproduction output in the sound reproduction device can be applied to a sound reproduction device of an environmental sensation device that allows the user to feel the noise of a truck traveling on a road adjacent to an apartment. At this time, the sound source data may be the noise, and the target reproduction level may be, for example, the noise level in each frequency band at the time of noise recording.

[0017]

As described above, according to the first aspect of the present invention, the target reproduction level of the reproduction output is set in a plurality of predetermined frequency bands, and the sound source signal converted into the digital signal is set. After reproducing the data, measuring the level of the reproduction output in each of the frequency bands and calculating the deviation from the target reproduction level, creating a digital filter having a pass gain in each frequency band that cancels the deviation Then, since the sound source signal data is filtered by the digital filter, the sound source signal data at the installation location of the sound reproducing device is used, so that complicated operations such as equalizer adjustment are not required, and the frequency at which the reproduced sound is set is set. A state close to a sound having characteristics can be approached.

According to the second aspect of the present invention, the maximum correction amount of the digital filter is restricted each time, and the sound pressure level of the reproduction output is corrected a plurality of times to gradually increase the level of the reproduction output. Is corrected, the reproduced sound can be reliably brought close to a state close to a sound having the set frequency characteristic.

According to the third aspect of the present invention, the sound source signal data is obtained by collecting a sound pressure signal of an impact sound emitted from a predetermined sound source room in a sound receiving room on a lower floor of the sound source room. After A / D conversion of the sampled sound pressure signal, a floor impact sound level in a frequency band having a plurality of preset frequencies as center frequencies is measured using the A / D converted quantized data. In addition to the floor impact sound data at the time of doing, since the target reproduction level is the floor impact sound level in each of the calculated frequency bands, the reproduction output of a floor impact sound reproduction device such as a floor impact sound sensation device, Correction can be easily made according to the installation location.

According to the fourth aspect of the present invention, the sound source signal data is obtained by collecting a sound pressure signal of noise generated in a predetermined sound source room in a sound receiving room adjacent to the sound source room. ,
After the A / D conversion of the collected sound pressure signal, the A / D
Using the D-converted quantized data, a sound pressure level in a frequency band having a plurality of preset frequencies as center frequencies is calculated, and a sound pressure level difference between the sound source room and the sound receiving room is calculated. In addition to the sound pressure data in the sound receiving room at the time of the calculation, the target reproduction level is set to the sound pressure level in each of the calculated frequency bands. The reproduction output can be easily corrected according to the installation location.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a reproduction output adjustment system in a sound reproduction device according to the present embodiment.

FIG. 2 is a flowchart showing a method of correcting a reproduction output according to the embodiment.

FIG. 3 is a diagram showing a correction state of a reproduction output.

FIG. 4 is a diagram showing a method of measuring a floor impact sound.

FIG. 5 is a diagram showing a method for measuring the interstitial sound pressure level.

[Explanation of symbols]

1 playback waveform correction device (personal computer), 2 playback sound card, 3 amplifier, 4 speakers, 5 bodily sensation rooms,
6 microphones, 7 sound card for detection, 1
0,10A sound source device, 11 broadband noise generator, 12
Power amplifier, 13 speakers, 15 microphones,
20, 20A arithmetic unit for sound pressure level, 21 low noise amplifier, 22 A / D converter, 23 RAM, 24 frequency setting means, 25 digital low-pass filter, 26
Digital high-pass filter, 27 sound pressure level calculating means, sound pressure level difference calculating means.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2G064 AA05 AB15 BD02 CC03 CC19 CC29 CC35 DD25 DD29

Claims (4)

[Claims] 1. A sound reproducing apparatus for reproducing sound source signal data converted into a digital signal, wherein when correcting a sound pressure level of a reproduction output due to a space in which the sound reproducing apparatus is installed, a preset sound pressure level is set. In a plurality of frequency bands, the target reproduction level of the reproduction output is set, the sound source signal data is reproduced, and the level of the reproduction output in each of the frequency bands is measured to calculate a deviation from the target reproduction level. After that, to create a digital filter having a pass gain of each frequency band to cancel the deviation, the data obtained by filtering the sound source signal data by the digital filter, sound source signal data at the installation location of the sound reproduction device and A method for correcting a reproduction output in a sound reproduction device. 2. The sound reproducing apparatus according to claim 1, wherein a maximum correction amount of the digital filter for each time is regulated and a sound pressure level of a reproduction output is corrected a plurality of times. How to correct playback output. 3. The sound source signal data is obtained by collecting a sound pressure signal of an impact sound generated in a predetermined sound source room in a sound receiving room on a lower floor of the sound source room, and converting the collected sound pressure signal into an A / A signal. After the D-conversion, the A / D-converted quantized data is used as floor impact sound data when a floor impact sound level in a frequency band having a plurality of preset frequencies as center frequencies is calculated. 3. The method according to claim 1, wherein the target reproduction level is a floor impact sound level in each of the calculated frequency bands. 4. The sound source signal data is obtained by collecting a sound pressure signal of noise generated in a predetermined sound source room in a sound receiving room adjacent to the sound source room, and A / D converting the collected sound pressure signal. After that, using the A / D-converted quantized data, a sound pressure level in a frequency band having a plurality of preset frequencies as center frequencies is calculated, and a room between the sound source room and the sound receiving room is calculated. 2. The sound pressure level in the sound receiving room when the inter-sound pressure level difference is obtained, and the target reproduction level is a sound pressure level in each of the calculated frequency bands. A method of correcting a reproduction output in the sound reproduction device according to claim 2.