close

Вход

Забыли?

вход по аккаунту

?

DESCRIPTION JP2001339262

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 JP2001339262
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an
acoustic apparatus, and more particularly, to an apparatus for driving a speaker with a low
frequency amplified signal.
[0002]
2. Description of the Related Art In an audio apparatus, a speaker is often driven by a signal
amplified in a low range in order to obtain a flat sound in the sense of hearing. However, if this is
done, the volume (volume) at which distortion starts to occur in the sound output from the
speaker becomes smaller by the amplification of the low band by being out of the dynamic range
of the power amplifier driving the speaker or the speaker itself. Therefore, to obtain a sound with
little distortion, the volume other than the low range becomes small.
[0003]
Therefore, conventionally, when the volume is increased, if the dynamic range of the power
amplifier deviates earlier, the magnitude of the input signal of the power amplifier is reversed,
and the dynamic range of the speaker is reversed first. In the case of deviation, the magnitude of
the output signal of the power amplifier is detected, and based on the detection result, distortion
is controlled by controlling the amplification factor in the low band so that the sound output
from the speaker is not distorted. Maintained the maximum volume not to occur.
10-04-2019
1
[0004]
For this reason, conventionally, a circuit for detecting the level of an input signal or output signal
of a power amplifier, that is, a relatively large signal is required, resulting in an increase in cost
and an increase in size. It was
[0005]
Therefore, the present invention is to provide an acoustic device capable of obtaining a flat sound
in hearing while maintaining the maximum volume free from distortion while suppressing the
increase in cost and the increase in size. To aim.
[0006]
In order to achieve the above object, according to the present invention, in an acoustic apparatus
provided with a bus amplification means which amplifies a low frequency band of a signal and
whose amplification degree is variable. Input level detection means for detecting the level of an
input signal, signal level calculation means for calculating the level of a signal output from a
predetermined circuit in the apparatus from the detection result of the input level detection
means, and the signal And a bus amplification degree control means for controlling the
amplification degree of the bus amplification means in accordance with the calculation result of
the level calculation means.
With this configuration, it is possible to obtain an auditory flat sound while maintaining the
maximum volume at which distortion does not occur without detecting the level of a relatively
large signal output from a predetermined circuit in the device. .
[0007]
Further, in the present invention, in an acoustic device provided with a bus amplification means
that amplifies the low band of the signal and the amplification degree is variable, assuming that
the level of the signal input to the device is maximum. Signal level calculating means for
calculating the level of a signal output from a predetermined circuit of the apparatus, and bus
amplification control means for controlling the amplification degree of the bus amplifying means
according to the calculation result of the signal level calculating means Is provided.
10-04-2019
2
According to this configuration, it is possible to obtain an aurally flat sound while maintaining
the maximum volume at which distortion does not occur without detecting the level of the signal.
[0008]
Further, in each of the above configurations, the bus amplification control means controls the
amplification degree of the bus amplification means in accordance with the magnitude
relationship between the calculation result of the signal level calculation means and the first
threshold. If the first threshold can be adjusted, the relationship between the level of the signal
output from a predetermined circuit in the device and the amplification of the low range can be
adjusted according to the dynamic range of the speaker .
[0009]
Further, in the above configuration, after the bus amplification control means reduces the
amplification degree in the bus amplification means, a state in which the calculation result in the
signal level calculation means is smaller than the second threshold is for a predetermined time or
more Then, if the amplification degree in the bus amplification means is increased, the output
level is set to such an extent that distortion does not occur even if the amplification degree in the
low band is increased after the amplification degree in the low band is reduced. Even if it
becomes smaller, the low-pass amplification degree will not be fixed while being reduced.
[0010]
Furthermore, by setting the second threshold value to a value smaller than the first threshold
value, it is possible to prevent the phenomenon that the amplification of the low band
periodically decreases or increases.
[0011]
Embodiments of the present invention will be described below with reference to the drawings.
The audio apparatus according to the first embodiment of the present invention has a block
diagram as shown in FIG. 1, and the input selection switch 1, volume adjustment circuit 2, bus
adjustment circuit 3, power amplifier 4, speaker 5, input level detection circuit And 6, an
operation unit 7, a display unit 8, and a system microcomputer 9.
10-04-2019
3
[0012]
The input selection switch 1 selects one of the signal output from the first sound source SS1 and
the signal output from the second sound source SS2 based on an instruction from the system
microcomputer 9.
The volume adjustment circuit 2 adjusts the level of the signal selected by the input selection
switch 1 according to the volume setting value given from the system microcomputer 9.
[0013]
The bus adjustment circuit 3 amplifies the low band of the signal processed by the volume
adjustment circuit 2 with an amplification degree according to the bus setting value given from
the system microcomputer 9.
The power amplifier 4 amplifies the power of the signal processed by the bus adjustment circuit
3.
The speaker 5 is driven by a signal whose power is amplified by the power amplifier 4.
[0014]
The input level detection circuit 6 detects the level of the input signal (the signal selected by the
input selection switch 1), and gives the detection result to the system microcomputer 9. As the
input level detection circuit 6, an A / D conversion circuit built in the system microcomputer 9
may be used. Further, as long as the first sound source SS1 and the second sound source SS2 are
configured to output the level of their own output signal as data, the data may be given to the
system microcomputer 9.
[0015]
10-04-2019
4
The operation unit 7 is for the user to input an instruction to the sound device. Under the control
of the system microcomputer 9, the display unit 8 displays the operation state of the apparatus
and the like. The system microcomputer 9 controls each unit so that the operation of the entire
apparatus corresponds to the user's instruction input from the operation unit 7. For example, the
volume setting value given to the volume adjusting circuit 2 and the bus setting value given to
the bus adjusting circuit 3 described above are controlled in accordance with an instruction input
from the operation unit 7.
[0016]
Next, the operation performed by the system microcomputer 9 will be described using the
flowchart shown in FIG. First, initialization is performed (# 101). Specifically, the low-pass
amplification degree change flag is set to 0, or the amplification degree of the bus adjustment
circuit 3 is set as instructed by the operation unit 7 or the like. Next, the detection result of the
input level detection circuit 6 is fetched (# 102). Next, an output level is calculated by performing
a predetermined operation using the detection result fetched in # 102 (# 103).
[0017]
Here, the output level refers to the level of the signal output from the bus adjustment circuit 3
when it deviates from the dynamic range of the power amplifier 4 earlier than the dynamic range
of the speaker 5 when the volume is increased. On the other hand, when the dynamic range of
the speaker 5 deviates earlier than the dynamic range of the power amplifier 4, the level of the
signal output from the power amplifier 4 is meant.
[0018]
Note that the level of the input signal is A [dB], the amplification degree of the signal in the
volume adjustment circuit 2 is B [dB], the amplification degree of the signal in the low range in
the bus adjustment circuit 3 is C [dB], the power amplifier 4 Level of the signal output from the
bus adjustment circuit 3 and the level O2 [dB] of the signal output from the power amplifier 4
are respectively O1 = A + B + CO2 = A + B + C + D. It becomes.
Therefore, the level of the input signal is given from input level detection circuit 6, and the
10-04-2019
5
amplification degree in volume adjustment circuit 2 and the amplification degree in bus
adjustment circuit 3 are controlled by oneself. The output level can be calculated by the equation.
[0019]
Next, it is determined whether the output level calculated in # 103 is larger than the first
threshold (# 104). As a result of the determination in # 104, if the output level calculated in #
103 is larger than the first threshold (Y in # 104), it is determined whether the low band
amplification degree change flag is 0 (#) 105). If the low band amplification degree change flag is
0 (Y in # 105), the amplification degree in the bus adjustment circuit 3 is decreased (# 106), and
1 is set in the low band amplification degree change flag (# 107) Thereafter, the process moves
to # 108. If the low band amplification degree change flag is not 0 (N of # 105), it proceeds to #
108 as it is. At # 108, if the timer is operating, the timer is stopped. After # 108, the process
moves to # 102.
[0020]
On the other hand, as a result of the determination in # 104, if the output level calculated in #
103 is not larger than the first threshold (N in # 104), it is determined whether 1 is set in the
low-pass amplification degree change flag. To do (# 109). As a result of the determination in #
109, if 1 is set in the low band amplification change flag (Y in # 109), the process proceeds to #
110, and if 1 is set in the low band amplification change flag. If (N at # 109), the process
proceeds to # 102.
[0021]
At # 110, it is determined whether the timer is operating. If the timer is in operation (Y of # 110),
the process proceeds to # 111, and if the timer is not in operation (N of # 110), the process
proceeds to # 112. At # 111, it is determined whether the count value of the timer is 3 seconds
or more. At # 112, the timer count is reset and then started. After # 112, the process moves to #
102.
[0022]
10-04-2019
6
As a result of the determination in # 111, if the count value of the timer is 3 seconds or more (Y
in # 111), the amplification degree in the bus adjustment circuit 3 is increased (# 112), and the
low band amplification degree change flag is 0 Is set (# 113), and thereafter, the process
proceeds to # 102, while if the count value of the timer is not 3 seconds or more (N of # 111),
the process proceeds to # 102.
[0023]
By the above processing, the level of the input signal, which is a relatively small signal, is
detected instead of actually detecting the output level, the output level is calculated from the
detection result, and the low frequency is calculated according to the calculation result.
Therefore, it is possible to obtain an auditory flat sound while maintaining the maximum volume
at which no distortion occurs while suppressing the cost increase and the size increase.
[0024]
Then, after reducing the amplification level in the low band, if the state where the output level is
smaller than the first threshold continues for 3 seconds or more, the amplification level in the
low band is increased (returned to the original). Even if the output level is reduced to such an
extent that distortion does not occur even if the amplification degree is increased, the low-pass
amplification degree is not fixed while being reduced, so that the capability of the device can be
effectively utilized. Become.
[0025]
A sound device according to a second embodiment of the present invention will be described.
The block diagram of the audio device of the second embodiment is the same as that of the first
embodiment shown in FIG. 1, but the operation of the system microcomputer 9 is different, so
only the different part will be described.
[0026]
The operation of the system microcomputer 9 in the second embodiment will be described with
reference to the flowchart shown in FIG.
10-04-2019
7
First, initialization is performed (# 201).
Specifically, the low-pass amplification degree change flag is set to 0, or the amplification degree
of the bus adjustment circuit 3 is set as instructed by the operation unit 7 or the like. Next, the
detection result of the input level detection circuit 6 is fetched (# 202). Next, an output level is
calculated by performing a predetermined operation using the detection result fetched in # 202
(# 203).
[0027]
Next, it is determined whether the output level calculated in # 203 is larger than the first
threshold (# 204). As a result of the determination in # 204, if the output level calculated in #
203 is larger than the first threshold (Y in # 204), it is determined whether the low band
amplification degree change flag is 0 (# 205) . If the low band amplification degree change flag is
0 (Y in # 205), the amplification degree in the bus adjustment circuit 3 is decreased (# 206), and
1 is set in the low band amplification degree change flag (# 207) Thereafter, the process moves
to # 208. If the low band amplification degree change flag is not 0 (N in # 205), the process
proceeds to # 208 as it is. At # 208, if the timer is operating, the timer is stopped. After # 208,
the process moves to # 202.
[0028]
On the other hand, as a result of the determination in # 204, if the output level calculated in #
203 is not larger than the first threshold (N in # 204), it is determined whether or not 1 is set in
the low band amplification degree change flag. To do (# 209). As a result of the determination in
# 209, if 1 is set in the low band amplification degree change flag (Y in # 209), the process
proceeds to # 210. On the other hand, if 1 is set in the low band amplification degree change
flag. For example (N of # 209), it moves to # 202.
[0029]
At # 210, it is determined whether the timer is operating. If the timer is in operation (Y in # 210),
the process proceeds to # 211. If the timer is not in operation (N in # 210), the process proceeds
10-04-2019
8
to # 212. In # 211, it is determined whether the count value of the timer is 3 seconds or more. At
# 212, the timer count is reset and then started. After # 212, the process moves to # 202.
[0030]
As a result of the determination in # 211, if the count value of the timer is 3 seconds or more (Y
in # 211), the process proceeds to # 213, while the count value of the timer is not 3 seconds or
more (N in # 211 ), Shift to # 202. In # 213, it is determined whether the output level calculated
in # 203 is smaller than a second threshold which is smaller than the first threshold.
[0031]
As a result of the determination in # 213, if the output level calculated in # 203 is smaller than
the second threshold (Y in # 213), the amplification degree in the bus adjustment circuit 3 is
increased (# 214), and the low-pass amplification degree The change flag is set to 0 (# 215), and
then the process proceeds to # 202, while if the output level calculated in # 203 is not smaller
than the second threshold (N in # 213), the process proceeds to # 202 as it is Do.
[0032]
Here, in the first embodiment, depending on the level of the input signal, the output level
becomes smaller than the first threshold when the amplification in the low band is decreased,
while the output level is decreased when the amplification in the low band is increased. Becomes
larger than the first threshold, but at this time, as shown in FIG. 4 (A), the amplification of the low
band periodically decreases or increases, and the low pitch of the reproduced sound swells. Will
occur.
[0033]
On the other hand, in the second embodiment, when the calculated output level becomes larger
than the first threshold by the above processing, the amplification of the low band is reduced and
the calculated output level is higher than the first threshold. If the state of small continues for 3
seconds or more, and the output level at that time is smaller than the second threshold, which is
a value smaller than the first threshold, the amplification of the low band is increased. If the
difference between the first threshold and the second threshold is set to be larger than the
change in amplification of the low band, as shown in (b) of FIG. To avoid the problem of waviness
in the low frequency range of the reproduced sound due to the amplification degree in the low
frequency range, in order to make it possible to effectively utilize the device capacity without
becoming large and large. Can.
10-04-2019
9
[0034]
A sound device according to a third embodiment of the present invention will be described.
The block diagram of the audio device of the third embodiment is the same as that of the first
embodiment, but the operation of the system microcomputer 9 is different, so only the different
part will be described.
[0035]
The operation of the system microcomputer 9 in the third embodiment will be described with
reference to the flowchart shown in FIG.
First, initialization is performed (# 301).
Specifically, the value of the variable x is set to 0, and the amplification degree of the bus
adjustment circuit 3 is set as instructed by the operation unit 7. Next, the detection result of the
input level detection circuit 6 is fetched (# 302). Next, an output level is calculated by performing
a predetermined operation using the detection result fetched in # 302 (# 303).
[0036]
Next, it is determined whether the output level calculated in # 303 is larger than the first
threshold (# 304). As a result of the determination in # 304, if the output level calculated in #
303 is larger than the first threshold (Y in # 304), the amplification degree in the bus adjustment
circuit 3 is decreased (# 305), and the value of the variable x Is increased by 1 (# 306), and if the
timer is in operation, the timer is stopped (# 307). After # 307, the process moves to # 302.
[0037]
10-04-2019
10
On the other hand, as a result of the determination in # 304, if the output level calculated in #
303 is not larger than the first threshold (N in # 304), it is determined whether the value of the
variable x is not 0 (# 308) . As a result of the determination in # 308, if the value of the variable
x is not 0 (Y in # 308), the process proceeds to # 309, while if the value of the variable x is 0 (N
in # 308), # 302 Transition to
[0038]
In # 309, it is determined whether the output level calculated in # 303 is smaller than a second
threshold which is smaller than the first threshold. If the output level calculated in # 303 is
smaller than the second threshold (Y in # 309), the process proceeds to # 310. If the output level
calculated in # 303 is not smaller than the second threshold (# 309 N) Move to # 307.
[0039]
At # 310, it is determined whether the timer is operating. If the timer is in operation (Y in # 310),
the process proceeds to # 311. If the timer is not in operation (N in # 310), the process proceeds
to # 312. At # 311, it is determined whether the timer count value is 3 seconds or more. At step
# 312, the timer count is reset and then started. After # 312, the process moves to # 302.
[0040]
As a result of the determination in # 311, if the count value of the timer is 3 seconds or more (Y
in # 311), the amplification degree in the bus adjustment circuit 3 is increased (# 313) and the
value of the variable x is decreased by 1 Then (# 314), the process proceeds to # 302, while if
the count value of the timer is not 3 seconds or more (N of # 311), the process proceeds to #
302.
[0041]
According to the above process, in the third embodiment, when the output level becomes larger
than the first threshold, the amplification factor in the low band is decreased, and the output
level is smaller than the second threshold smaller than the first threshold. Since the amplification
of the low band is increased when L continues for 3 seconds or more, the low band amplification
causes the low pitch of the reproduced sound as in the second embodiment. Can be prevented.
10-04-2019
11
[0042]
Further, in the second embodiment, after the state where the output level is smaller than the first
threshold continues for 3 seconds or more, amplification in the low band is performed when it
becomes temporarily smaller than the second threshold under the influence of noise or the like.
A phenomenon may occur in which the amplification factor of the low band is switched
unnecessarily after it becomes small again after the degree has once increased, but this can be
prevented in the third embodiment.
[0043]
In the above embodiments, the level of the input signal is detected, and the output level is
calculated from the detection result. Instead of this, the level of the signal is not actually detected.
The output level may be calculated on the assumption that the level of the input signal is
maximum, and the amplification of the low band may be controlled according to the calculation
result.
In this way, a circuit for detecting the level of the signal is not necessary, so that cost increase
and size increase can be further suppressed, and a sound that is aurally flat while maintaining the
maximum volume at which distortion does not occur. You can get
In addition, since the device side (system microcomputer 9) does not switch the amplification
level of the low band independently only when the input level changes (in other words, the
apparatus side switches the amplification degree of the low band independently) Since it is only
when the user himself adjusts the volume or tone), the user is less likely to notice that the lowrange amplification degree has been independently switched on the apparatus side, and the
reproduction quality is improved.
[0044]
In each of the above embodiments, for example, setting the first threshold from the operation
unit 7 or the like makes it possible to set the first threshold to an appropriate value according to
the dynamic range of the connected speaker. For multiple types of speakers with dynamic range,
the ability of the speakers can be maximized.
10-04-2019
12
This is effective when a plurality of speakers having different dynamic ranges may be connected
(for example, when the speakers are externally attached).
[0045]
Also, if it is possible to set from the outside whether the system microcomputer 9 calculates the
level of the signal output from the bus adjustment circuit 3 or the level of the signal output from
the power amplifier 4, distortion does not occur at the maximum. In order to be able to obtain a
flat sound in the sense of hearing while maintaining the volume, when the volume is increased,
the dynamic range of the power amplifier 4 deviates earlier than the dynamic range of the
speaker 5, and the power Since the present invention can cope with both cases where it deviates
from the dynamic range of the speaker 5 earlier than the dynamic range of the amplifier 4, it is
possible to reduce the restriction on the dynamic range of connectable speakers (in other words,
To drive speakers with a wider variety of dynamic ranges. Also, it is possible to obtain a
perceptually flat sound while maintaining the maximum volume distortion does not occur).
[0046]
In each of the above embodiments, the condition for increasing the amplification factor in the
low band is that the calculated output level is smaller than the threshold for three seconds or
more, but this time has another appropriate length. It may be set to another or may be set from
the outside.
[0047]
Further, in the first embodiment and the second embodiment, the system microcomputer 9
independently switches the amplification of the low band to two stages based on the calculated
output level, but in the same manner as the third embodiment. You may switch to three or more
steps.
On the other hand, in the third embodiment, the system microcomputer 9 independently
switches the amplification of the low band to three or more stages based on the calculated output
level, but in the first and second embodiments, Similarly, it may be switched in two stages.
Moreover, although the speaker was incorporated in said each embodiment, the speaker may be
external.
10-04-2019
13
[0048]
As described above, according to the present invention, the level of the output signal, which is a
relatively large signal, is not actually detected, but the level of the input signal, which is a
relatively small signal, is detected. Since the level of the output signal is calculated from this
detection result and the amplification of the low band is controlled according to this calculation
result, distortion and distortion increase can be suppressed. You will be able to get a flat sound
on your hearing while maintaining a maximum volume that does not occur.
[0049]
Further, according to the present invention, the level of the output signal is calculated assuming
that the level of the input signal is maximum, instead of actually detecting the level of the signal,
and amplification of the low band is performed according to the calculation result. Since the
degree is controlled, it is possible to obtain an aurally flat sound while maintaining the maximum
volume at which no distortion occurs while further suppressing cost increase and size increase.
[0050]
Further, according to the present invention, since the threshold value for switching the low-pass
amplification degree can be appropriately set according to the dynamic range of the connected
speaker, for a plurality of types of speakers having different dynamic ranges, You will be able to
maximize the ability of the speaker.
[0051]
Further, according to the present invention, even if the output level is reduced to such an extent
that distortion does not occur even if the amplification in the low band is increased, the
amplification in the low band is not fixed while being reduced. Will be able to make effective use
of their abilities.
[0052]
Further, according to the present invention, in order to be able to effectively utilize the capability
of the apparatus, the amplification of the low band does not periodically decrease or increase,
and the amplification of the low band can be reduced. It is possible to prevent the problem that
undulation occurs in the low frequency range of the reproduced sound as a result.
[0053]
10-04-2019
14
Brief description of the drawings
[0054]
FIG. 1 is a block diagram of an acoustic device according to an embodiment of the present
invention.
[0055]
FIG. 2 is a flow chart showing the operation of the system microcomputer in the first
embodiment of the present invention.
[0056]
It is a flow chart which shows operation of a system microcomputer in a 2nd embodiment of the
present invention.
[0057]
FIG. 4 is a diagram showing changes in output level.
[0058]
FIG. 5 is a flow chart showing the operation of the system microcomputer in the third
embodiment of the present invention.
[0059]
Explanation of sign
[0060]
REFERENCE SIGNS LIST 1 input selection switch 2 volume adjustment circuit 3 bus adjustment
circuit 4 power amplifier 5 speaker 6 input level detection circuit 7 operation unit 8 display unit
9 system microcomputer
10-04-2019
15
Документ
Категория
Без категории
Просмотров
0
Размер файла
25 Кб
Теги
jp2001339262, description
1/--страниц
Пожаловаться на содержимое документа