close

Вход

Забыли?

вход по аккаунту

?

JPH0662499

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JPH0662499
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a
sound field formed by a plurality of sound reproducing devices, and in particular, a reflection for
removing a reflected wave generated in sound reproduction in a small space (for example, a
cabin space etc.). It relates to a wave removing device.
[0002]
2. Description of the Related Art In recent years, it has become possible to approximately
reproduce various spaces by creation control of audio signals using a DSP (Digital Signal
Processor) or the like. However, most of them only control the acoustic energy (amplitude) and
do not take account of the sharing of the electric signal in many cases. For example, in the
control of the acoustic energy, the speaker group surrounding the listener is a hall etc. By the
method of approximating the energy distribution of the sound of.
[0003]
However, in the above conventional method, only the energy (amplitude) of the sound is
processed, and the wave front of the sound emitted from the speaker is not processed. There is a
problem that the sound image presentation in front of (see FIG. 4) is ignored. In FIG. 4, the
concentric broken lines from the speakers SR and SL indicate the wave fronts of the sounds
10-05-2019
1
emitted from the speakers SR and SL, respectively. FIG. 5 shows an example of creation of an
energy control type sound field space using a DSP as a conventional example, but the sound field
by the wave front of the sound output from each of the speakers S1 to S8 is not considered.
[0004]
The present invention has been made in view of the above problems, and removes reflected
waves generated in acoustic reproduction in a small space, and even by a small space, it is
possible to use a wavefront from the front as in the case of listening in a wide space. An object of
the present invention is to provide a reflected wave component removing device capable of
obtaining a sound field.
[0005]
SUMMARY OF THE INVENTION In order to achieve the above object, a reflected wave component
removing device according to the present invention is a front of main reproduction output means
for reproducing and outputting corresponding left and right component signals of an acoustic
signal to be reproduced. Sub-reproduction output means for reproducing and outputting a
reflection wave cancellation signal to be provided at an arbitrary position around the listener
position and to cancel the reflection wave components by the left and right side component
signals at the listener position; Signal generation means, and the reflected wave cancellation
signal generation means respectively delay the left and right side component signals by the
propagation time of the left and right side component signals from the main reproduction output
means to the sub reproduction output means, respectively. A delay unit for obtaining a delay
signal, an amplitude control unit for controlling the amplitude of each delay signal according to
the amplitude at which the left and right component signals are reproduced by the main
reproduction output means, and an amplitude control unit It has a synthetic-inversion unit for
the phase inversion process after the control signal was synthesized, and, and generating a
reflected wave cancellation signal based on the phase inversion process results in synthesis and
reversing unit.
[0006]
With the above configuration, the apparatus for removing reflected wave components according
to the present invention has the means for generating reflected wave cancellation signal for
transmitting left and right side component signals of the acoustic signal to be reproduced by the
delay unit from the main reproduction output means to the auxiliary reproduction output means.
The respective delay signals are obtained by delaying the propagation time of the left and right
side component signals to obtain the respective delay signals, and the amplitude control unit
10-05-2019
2
respectively controls the amplitude according to the amplitude at which the left and right side
component signals are reproduced by the main reproduction output means. To obtain an
amplitude control signal of
Further, the amplitude control signals are combined by the combining / inversion unit and then
phase inversion processing is performed to generate a reflected wave cancellation signal based
on the result of the phase inversion processing.
Then, the auxiliary reproduction output means is provided at an arbitrary position around the
listener position, and reproduces and outputs the reflected wave cancellation signal so as to
cancel the reflected wave component by the left and right side component signal at the listener
position.
[0007]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows an embodiment of a
speaker arrangement in a small space including a reflected wave component removing device
according to the present invention. In FIG. 1, a portion enclosed by a broken line in a rectangular
shape is an example of a small space, and SL and SR are left and right speakers as main
reproduction output means, and S1 to S4 are auxiliary speakers as auxiliary reproduction output
means, A, B is the position of the listener, .tau.1 to .tau.4 are the sound propagation time from the
speaker SR to the auxiliary speakers S1 to S4, .tau.1 'is the sound propagation time from the
speaker SL to the speaker S1, .tau.2 "is from the speaker SR to the speaker S2 20 is an auxiliary
speaker drive signal circuit as a reflected wave cancellation signal reproduction means, and the
auxiliary speaker drive signal circuits 20 respectively connected to the auxiliary speakers S1 to
S4 respectively have a reflected wave component removing device Configure.
[0008]
In FIG. 1, the speakers SR and SL mean speakers as the speakers R and L in a wide space, and a
sound image (a sound image at the center) at the listening position A is obtained by ER = EL. At
the listening position B, the sound image is in front with ER> EL.
[0009]
10-05-2019
3
Next, for the sake of explanation, let the listening position be the position indicated by the
symbol A. Then, the auxiliary speaker S1, the speaker S2, and the auxiliary speaker S3 and the
speaker S4 are disposed on the side surface of the small space. Here, assuming that the drive
signal of the side speaker S1 is E1, E1 can be expressed by the following equation 1: E1 = − {k1 ·
ER (t−τ1) + kl ′ · EL (t−τ1 ′)} (1) As for the drive signal E1, ER is delayed for a time τ1
that the signal from the speaker SR propagates to reach S1. The amplitude of the signal ER (tτ1) multiplied by k1 and the amplitude of the signal EL (t-τ1 ') delayed by EL by the time τ1'
when the signal from the speaker SL propagates and reaches S1 is k1 Here, k1 and k1 'indicate
magnitudes (amplitudes) of the sound waves from the speaker SR and the speaker SL at the
position of the speaker S1.
[0010]
FIG. 2 is a block diagram showing a configuration example of the reflected wave cancellation
signal reproduction means (drive signal circuit 20 for the auxiliary speaker Sn), and 21 is a time
τ n at which the audio signal ER from the speaker SR propagates to reach the speaker Sn. A
delay unit comprising a satisfying delay circuit, 22 a delay unit comprising a delay circuit
satisfying a time τ n which the audio signal EL from the speaker SL propagates to reach the
speaker Sn, 23 an amplitude control unit comprising a gain control circuit Reference numeral 24
denotes a synthesis / inversion unit.
[0011]
In FIG. 2, the drive signal En of the auxiliary speaker Sn is synthesized by controlling the
amplitude of the output ER (t−τn) of the delay unit 21 and the output ER (t−τn ′) of the
delay unit 22 by the amplitude control unit 23. It is synthesized by the inverting unit 24 and
obtained by inverting the polarity.
Thereby, the output (sound wave) from the auxiliary speaker Sn by the drive signal En of the
sound wave from the speaker SR and the speaker SL in the vicinity of the auxiliary speaker Sn is
canceled.
[0012]
Further, FIG. 3 shows a specific example of the drive signal circuit of the speakers S1, S2 and S3
taking the drive signal E1 as an example, wherein 31 to 33, 331 'to 33' are delay circuits, 34 and
10-05-2019
4
35 are gain control circuits, Is an adder circuit and 37 is an inverter circuit.
[0013]
In FIG. 3, the signal ER is a time τ2 when the signal ER from the speaker SR propagates to the
time τ1 to S1, a time τ2 to the S2, a time τ3 to the S3, a time τ4 to the S4 (see FIG. 1)
Through the delay circuits 31, 32, and 33, the signal EL propagates from the speaker SL to time
τ1 'to reach S1, time τ2' to reach S2, and time τ3 'to reach S3. It passes through the delay
circuits 31 ', 32', 33 'which satisfy the time .tau.4' (see FIG. 1) to reach S4.
The drive signal E1 of the speaker S1 includes the output ER (t-.tau.1) of the delay circuit 31 and
the output ER (t-.tau.1 ') of the delay circuit 21' by the gain control circuits 34 and 35. It is
obtained by multiplying by k1 and k1 'and adding the outputs of the gain control circuit 34 and
the gain control circuit 35 by the adding circuit 36 and inverting the polarity by the inverting
circuit 37. Thereby, in the vicinity of the auxiliary speaker S1, the sound waves from the speaker
SR and the speaker SL are canceled by the sound wave by the drive signal E1 of the auxiliary
speaker S1. In the example of FIG. 3, the delay circuits 21, 22, 23, 21 ', 22' and 23 'are connected
in series, but may be connected in parallel.
[0014]
Similarly, for the speaker assistances S2, S3 and S4, the listener mainly listens to the sound
waves from the speaker SR and the speaker SL, which are main sound sources, by canceling the
sound waves from the speaker SR and the speaker SL at each speaker position. Because of this, it
is possible to approximate the same acoustic effect without the space division (for example, the
wall of the cabin, etc.) indicated by the broken line in FIG.
[0015]
Further, in addition to the direct wave as shown in FIG. 1 as the output of the speakers S1 and S2
etc. in the drive signal En, for example, the output of the speaker S2 is τ2 ′ ′ in FIG. Reflection
paths, such as paths, can also be included.
In this case, for example, the drive signal E2 of the speaker S2 of FIG. 1 is expressed by the
following equation. E1 = − {k 2 · ER (t−τ 2) + k 2 ′ · EL (t−τ 2 ′) + k 2 ′ ′ EL (t−τ 2 ′
10-05-2019
5
′)}
[0016]
As described above, according to the present invention, the reflected component on the wall
surface constituting a small space such as a vehicle interior is canceled by the sound source of
the auxiliary speaker as the reflected wave component removing device of the present invention.
The wave front from the main sound source speaker provided on the front is the main
component, and the reflected wave generated at that time in acoustic reproduction in a small
space is removed, and the sound from the front from the wave front as in the case of listening in
a wide space even in a small space You can get a place.
10-05-2019
6
Документ
Категория
Без категории
Просмотров
0
Размер файла
14 Кб
Теги
jph0662499
1/--страниц
Пожаловаться на содержимое документа