close

Вход

Забыли?

вход по аккаунту

?

JPH03143195

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 JPH03143195
[0001]
Industrial Application Field] This invention relates to a multi-amplifier system speaker system for
improving characteristics as a speaker system and improving sound quality by performing digital
signal processing suitable for each speaker for each channel . [Conventional technology] In a
multi-way speaker system in which a plurality of dedicated speakers for one frequency band are
conventionally used in combination, a system using an LC network composed of a coil and a
capacitor, and a dedicated for each band (channel) A multi-amplifier system using a channel
divider of Channel dividers used in LC networks and multi-amplifiers have the function of
frequency dividing the audio frequency band into several necessary frequency bands and
supplying an acoustic signal to a speaker dedicated to the corresponding band. In the multiamplifier system, digitization of channel dividers composed of electronic circuits has been
advanced. FIG. 7 is an embodiment disclosed in Japanese Utility Model Application Publication
No. 59-101517 and is a block diagram showing an example of a speaker system by the abovementioned multi-amplifier system using a digital system channel divider. In the figure (2), (2+). (2
□), ... (2- is a plurality of power amplifiers, (3). (3+), (3a), ... (3n) are a plurality of speaker units,
(4) is a channel divider, and a plurality of linear phase FIR filters (41), (4 □), ... (4) ,, 1 consists of.
(411), (422),... (4,...) Are a plurality of filter coefficient variable devices, each of which is
calculation means for providing filter coefficients for giving the above linear phase FIR filter a
desired frequency division characteristic. (5). (S +), (5g) and-(5n) are a plurality of D / A
converters. In the multi-way speaker system described above, a digital signal input is applied to
the channel divider (4) and a linear phase FIR filter (41). (4 □), ... (41) In order to give desired
frequency division characteristics, the filter coefficient variable devices (4, t), (4 °), ... (4 ,, n) and
the filter coefficients of Convoluted. Next, linear phase FIR filters (4), (411, (4)). The output of (4
°) is each D / A converter (5). (51), (sx),... (57) are converted to analog signals, and the power
amplifiers (2), (211, (2 □),. The signal is amplified and supplied to speaker units f3), (31), (3
08-05-2019
1
□),... (3o) and converted into sound.
[Problems to be Solved by the Invention] As an advantage of the above multi-way speaker
system, linear phase FIR filters (41, (4 + 1, (4 zl,... (4,) are used as channel dividers maintain
linear phase characteristics) While being able to divide the band into a desired frequency band.
Therefore, the delay time of the filter becomes constant (linear phase) with respect to the
frequency regardless of the band division characteristic. However, the disadvantage is that each
linear phase FIR filter (4, 1) needs to be divided into bands according to the corresponding
frequency band. The delay time of (4 □), ... (4o) has a difference, and as a result, the radiated
sound from each speaker (3,, + 3 □), ... (3 °) is not the same as the delay time 1 There is a
problem that the phase shift and the disturbance of the output sound pressure characteristic are
caused, and the faithful reproduction of the sound becomes difficult. The present invention has
been made to solve the problems as described above, and the delay time of the sound radiated
from each speaker is matched, and as a result, high fidelity sound is obtained by flattening the
overall sound pressure frequency characteristic. An object of the present invention is to obtain a
multi-amplifier speaker system that realizes reproduction. [Means for Solving the Problems 1 In
the multi-way speaker system according to the present invention, digital signal processing
circuits for characteristic control are used instead of conventional channel dividers for one
frequency band division, and A band division circuit consisting of a linear phase FIR filter for
each channel, an inverse filter for flattening the output sound pressure characteristic of the
speaker, and a delay time correction circuit for correcting the delay time between channels are
provided. The output sound pressure characteristics of the radiation sound from each speaker
and the total radiation sound are flattened, and the correction of the delay time and the phase
difference is accurately realized. [Operation] The multi-way speaker system according to the
present invention can flatten the output sound pressure characteristic and correct the delay time
and phase difference by the linear phase FIR filter provided for each channel, the inverse filter of
the speaker characteristic, and the delay correction circuit. Realize the correction. It has the
effect of realizing high fidelity sound reproduction without sound pressure distortion.
Hereinafter, an embodiment of the present invention will be described with reference to the
drawings. FIG. 1 is a block diagram showing an embodiment of a multi-amplifier speaker system
according to the present invention. In the figure, (2) is a power amplifier and includes a plurality
of power amplifiers (2, l, (2 □),... (2 □), and (3) is a speaker unit. Speaker units (31), (32), ... (3n)
are included.
(4) is a band dividing circuit, which has a plurality of linear phase FIR filters (4t), (42),... (4n), and
filters for making each of the linear phase FIR filters have desired frequency division
characteristics Coefficient generation circuit, (4 □), (4 □ 2). · · · · · (4, I, and has. (5) is a D / A
conversion circuit including a plurality of D / A converters (511, (5 g),... (5 °). (6) are also a
plurality of A / D converters [6+), (6 □). ... f6. (7) is an inverse filter for flattening the output
08-05-2019
2
sound pressure characteristics, and a plurality of linear phase FIR filters (7I), (72) 5 = (7,) and
The inverse filter coefficient generation circuit (7111, (7 2), ... (7, 1, 1). (8)は? 31? A
delay time correction circuit including several delay time correction circuits (811, (82),..., (8,).
(20) shows a microphone. In FIG. 1, an analog input signal is converted into a digital signal by an
A / D conversion circuit (6). In this embodiment, an A / D conversion circuit is provided for each
channel, but one having the same sampling frequency can be shared. Next, the digital output
signal of the A / D conversion circuit (6) is led to the band division circuit (4). In the band
division circuit (4), filter coefficient generation circuits (4 □), (4 □), and (4 □) for obtaining
predetermined frequency band division characteristics by the linear phase FIR filters (4,), (4 □),.
4, □) ... (4. And the digital output signal is divided into desired frequency bands. The digital
signal obtained as a result of the convolution operation is further led to the inverse filter (7) for
flattening the output sound pressure characteristic of each speaker unit, and the linear phase FIR
filter is the same as the band division circuit (4) (7 + 1, (7 □),... (7 □), the inverse filter
coefficient generation circuit (7 ++), (722),. Convolutional operation is carried out with the signal
from (4) to correct the output sound pressure characteristic. By the way, the signal that has
passed through the band division circuit (4) and the inverse filter (7) is unique to each channel,
and has linear band phase characteristics (constant delay time) while having frequency band
division characteristics by adopting the linear phase FIR filter and introducing the inverse filter.
And flatten the output sound pressure characteristics. However, the delay time between the
channels and the phase generally do not match.
Then, the signal that has passed through the inverse filter (7) is led to the delay time correction
circuits [a,), (S □),. It is necessary to correct the delay time difference and the phase difference
between each channel. This is the total delay time and the total delay time including the delay
time t +, tz '· · · 111 due to sound wave pressure from each speaker unit (3,), (3 □), ... [3,) to the
microphone (20) The delay time adjustment of each delay time correction circuit (s,), (8 □),...
(8n) is performed so that the phase matches. Specifically, each delay time correction circuit (S +).
The delay time difference may be corrected with reference to any one of (8 □),..., (8o). Next, the
digital signal corrected by the delay time correction circuit (8) is converted into an analog signal
by each D / A conversion circuit (s +), (M,... (5, 1) and each power amplifier (211). (22)... (2 □),
the light is led to the speaker units (3 + 1, (3 □),... (3 □) to emit sound. This solves the problem
of the delay time mismatch 9 phase shift of each radiation sound and the disturbance of the
overall output sound pressure characteristics resulting from the conventional problem, and
realizes a multi-amplifier speaker system performing faithful sound reproduction. It becomes
possible. The A / D conversion circuit (6) and the band division circuit (4). The inverse filter, the
filter (7), the delay correction circuit (8) and the D / A conversion circuit (5) are digital signal
processing circuits for characteristic control in the present invention. This part is a conventional
channel divider for frequency band division (not just for frequency band division). It is a circuit
that can perform characteristic correction and delay correction. Of course, the order of the band
division circuit (4), the inverse filter (7) and the delay time correction circuit (8) may be
08-05-2019
3
interchanged. The delay correction circuit can be omitted if the delay time is 0 seconds. FIGS. 2
and 3 are block diagrams showing other embodiments of the multi-amplifier speaker system
according to the present invention. In FIGS. 2 and 3, the same or corresponding parts as in FIG. 2
and 3 differ from FIG. 1 in that the configuration of the delay time correction circuit (8) is
specifically shown. In FIG. 2, the delay time correction circuit (8) comprises delay control circuits
(81), (8 □),... (8o), and buffer memories (811) for storing signal data at intervals. (8 2), ... (8 o).
In FIG. 2, digital signals derived from the inverse filter (7) are temporarily buffered by the delay
control circuits (81), (82),... (8o) as buffer memories (8), [82]. The data is stored in (8,...) And then
this data is called after a predetermined time. By using the delay control circuit and the buffer
memory as described above, the delay correction circuit (8) can be miniaturized. On the other
hand, in the embodiment shown in FIG. 3, the delay time correction circuit (8) is a linear phase
FIR filter (9,) (9.quadrature.),... (9n) and a delay coefficient generation circuit (9111, (922)). ... (9
,,) It consists of. The digital signal derived from the inverse filter (7) is subjected to linear phase
FIR filters (91), (9 □),... (97) to generate delay coefficient generating circuits (9 □), (q zz),.
Convoluted with the signal from 9), and the necessary delay is added. When the linear phase FIR
filter and the delay coefficient generation circuit are used as described above, the configuration is
similar to that of the band division circuit (4) and the inverse filter (7), and there is an advantage
that the circuit design is simplified. FIG. 4 is a block diagram showing a simplified example of the
digital signal processing circuit of the multi-amplifier speaker system according to the present
invention. From the embodiment shown in FIG. 1, since the basic circuit configuration of the
band dividing circuit (4) and the inverse filter (7) is the same, the filter coefficient generating
circuit (411), (4 2), ... (4) , N) coefficient data and the inverse filter coefficient generation circuit
(V, +), (7 □,),-· · · · · · · · (7,) coefficient data obtained by the convolution operation The band
division circuit (4) and the inverse filter (7) can be integrated by performing a convolution
operation on (band division / inverse filter coefficient) and the input signal data from the A / D
conversion circuit (6). The embodiment shown in FIG. 4 is a block diagram in which integration is
carried out in this manner, in which the digital signal processing circuit portion is intended to be
simplified. Similarly, FIG. 5 is a block diagram showing another simplified example of the digital
signal processing circuit of the multi-amplifier speaker system according to the present
invention. In FIG. 5, the coefficient data of the filter coefficient generation circuit (4,,), (4 2),...,
(4,,,), the inverse filter coefficient generation circuit (7 1, (y zz 1,... · (7, ...) coefficient data and
delay coefficient generator (9, ...). (9 □ 2), ... (9 °) coefficient data is convoluted.
A band division circuit (4) and an inverse filter (7) are obtained by performing a convolution
operation on the resulting coefficient data (band division / inverse filter / delay correction
coefficient) with the input signal data from the A / D conversion circuit (6). And the delay
correction circuit (8). In this case, the circuit can be further simplified than the embodiment
shown in FIG. However, as the delay time correction circuit (8), as shown in FIG. 3, linear phase
08-05-2019
4
FIR filters (911, (92),..., (9,) and delay coefficient generation circuits (9111, (9 □ 2),. It is
effective only when it is composed of (9 □). By the way, in the multi-amplifier speaker system
according to the present invention of FIGS. 2 to 5 as described above, flattening of the output
sound pressure characteristic and linear phase (delay time-constant) are realized for the radiation
sound from each speaker. , And each speaker (31), (3 □). By matching the delay times of the
radiated sound from (3 °), it is possible to obtain a multi-amplifier speaker system that realizes
high-fidelity sound reproduction. However, when the overall output sound pressure
characteristics that can be finally obtained can not be flattened as required due to design errors
or when it is desired to arbitrarily change the total output sound pressure characteristics, as
shown in FIG. The characteristic control can be finely performed by providing the integrated
sound pressure characteristic correcting linear phase FIR filter (13) and the integrated sound
pressure characteristic correction coefficient generating circuit (14) in the previous stage of. As
the integrated sound pressure characteristic correction coefficient generation circuit (14) in FIG.
6, when the integrated output sound pressure characteristic is flattened, the inverse of the
integrated sound pressure characteristic as the integrated sound pressure characteristic
correction coefficient generation circuit (14) It is sufficient to use coefficient data that gives
characteristics. When it is desired to change the characteristics arbitrarily, it is necessary to
calculate and use correction coefficient data for correcting the overall sound pressure
characteristics. As described above, according to the multi-amplifier speaker system of the
present invention, the digital signal processing circuit for characteristic control is used instead of
the conventional channel divider for one frequency band division, and each frequency band is
used. In addition, a band division circuit, an inverse filter for flattening the output sound pressure
characteristic of the speaker, and a delay time correction circuit for correcting the delay time
between channels are provided to correct the output sound pressure characteristic of the
radiated sound from each speaker, delay The correction of the time difference and phase
difference, and the flattening of the output sound pressure characteristic of the total radiation
sound, has the effect of realizing a speaker system capable of reproducing high-fidelity sound
without sound pressure distortion.
[0002]
Brief description of the drawings
[0003]
FIG. 1 is a block diagram showing one embodiment of a multi-amplifier speaker system according
to the present invention, and FIGS. 2 to 6 are block diagrams showing another embodiment of a
multi-amplifier speaker system according to the present invention. 1 is a block diagram showing
an example of a conventional multi-amplifier speaker system.
08-05-2019
5
(3), (3,), (3 ..., (3 n) is a speaker unit, (4) is a band division circuit, (5), [5+), (s □), ... (5 n) Is a D /
A conversion circuit, f6), (6, 1, (62), ... (6,) is an A / D conversion circuit, (7) is an inverse filter, (8)
is a delay time correction circuit, 81), (82), ... (8n) are delay (control) circuits. The same symbols
indicate the same or corresponding parts.
08-05-2019
6
Документ
Категория
Без категории
Просмотров
0
Размер файла
16 Кб
Теги
jph03143195
1/--страниц
Пожаловаться на содержимое документа