JPH08186886A - Sound control device - Google Patents

Abstract

PURPOSE: To realize the sound quality of the frequency characteristic according to a sound mode by providing a base reflex type speaker unit with a motor- driven port cover adjusting the length of a port and providing a port length control means controlling the driving of the port cover. CONSTITUTION: A bass reflex type speaker unit 5 is provided with the port cover 17 driven by a motor 18 adjusting the length of a port 15 and is provided with a port length control means 4 controlling the driving of the port cover 17. Therefore, the port length can be scrupulously and easily changed based on a sound switch 2. Namely, the port length control means 4 is provided with port cover control means including a target location setting means setting the target location of the port cover, an arithmetic means and a driving control means, a location signal detection means detecting the location of the port cover 17 and a port cover driving means. Thus, the change of the port length can be set to the target location based on a sound switch 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound control device for controlling the sound quality of audio equipment such as CD radio cassette recorders and mini component stereos.

[0002]

2. Description of the Related Art There is known a conventional sound control device provided with a sound control means for electrically changing a sound quality by controlling a gain based on a selection signal of a sound switch and a sealed speaker unit.

A bass reflex type speaker unit provided with a port for acoustically changing the low frequency characteristic is also known.

Further, it is also known to provide both a sound control means for electrically changing the sound quality and a bass reflex type speaker unit for acoustically changing the sound quality.

FIG. 5 is an overall block diagram of a conventional sound control device. In FIG. 5, a conventional sound control device 50 includes a sound switch 51.
A sound control means 52 and a bass reflex type speaker unit 54.

The sound switch 51 is composed of, for example, a slide switch or the like, and a desired sound mode A, B, C is selected according to the music, and selection signals A1, B1, C1 are selected.
Are provided to the sound control means 52.

The sound control means 52 comprises a sound mode determination control means 55, an equalizer section 56, and an amplification section 53. The sound mode determination control means 55 is composed of, for example, an encoding conversion means and a memory such as a ROM.

In the memory of the sound mode determination control means 55, a selection signal A1 from the sound switch 51 is previously stored.
Gain control data corresponding to B1 and C1 is set,
When the selection signals A1, B1 and C1 are input, the selection signal A
The low-frequency gain control signals T1, T2, the mid-frequency gain control signals M1, M2, and the high-frequency gain control signals K1, K2 coded by the coding conversion means on the basis of 1, B1, C1 are the low-frequency signals of the equalizer section 56. It is provided to the tone range circuit unit 58, the middle tone range circuit unit 59, and the high tone range circuit unit 60, respectively.

The equalizer section 56 is provided with a buffer 52, a low-range circuit section 58 capable of gain control, a middle-range range circuit section 59, and a high-range range circuit section 60, and is composed of, for example, a plurality of operational amplifiers (operational amplifiers) and switches. It

The gain control of the bass range circuit section 58 is performed by the encoded bass range gain control signals T1 and T2 from the sound mode determination control means 55. For example, when both the low frequency gain control signals T1 and T2 are at the L level, the gain does not change, and when the low frequency gain control signal T1 is at the L level and the low frequency gain control signal T2 is at the H level, the gain is increased. , Low-frequency gain control signal T1 is at H level, low-frequency gain control signal T2
Is at the L level, the gain is reduced, and the low frequency sound quality is set based on the mode selected by the sound switch 51.

Mid range circuit section 59 and high range circuit section 60
Similarly, for the gains of the respective signals, the encoded mid-range gain control signal M from the sound mode determination control means 55 is obtained.
1, M2 and high-frequency gain control signals K1, K2, and the mid-range sound quality and the high-range sound quality are set based on the mode selected by the sound switch 51.

The impedance conversion buffer 52 has an audio signal S2 having the same frequency characteristic as the input audio signal S1.
Is provided to the bass range circuit section 58.

The low tone range circuit section 58 receives the voice signal S2 from the buffer 52, and outputs the voice signal S3 whose gain is controlled based on the low range gain control signals T1 and T2 to the middle tone range circuit section 5.
9 to provide.

The mid-range circuit section 59 receives the audio signal S3 from the bass range circuit section 58 and receives the mid-range gain control signals M1 and M.
The audio signal S4 whose gain is controlled based on 2 is provided to the treble range circuit unit 60.

The treble range circuit section 60 receives the voice signal S4 from the middle range circuit section 59 and receives the treble range gain control signals K1 and K.
The audio signal S5 whose gain is controlled based on
To provide.

As described above, the equalizer section 56 performs gain control based on the selection signals A1, B1, and C1 from the sound switch 51, and the frequency characteristics of the input sound signal S1 in the low sound range, the middle sound range, and the high sound range. Is changed and the amplification unit 5
3 is output.

The amplifier 53 receives the audio signal S5 from the equalizer 56, performs impedance matching with the speaker 62, outputs the power-amplified audio signal S6, and drives the speaker 62 efficiently.

FIG. 6 is a sectional view of a speaker unit of a conventional sound control device. 6, in the bass reflex type speaker unit 54, a port 63 for changing the low frequency characteristic is formed in the lower portion of the front wall inside the housing 61, and the speaker 62 is fixed to the upper portion.

The acoustic change of the low frequency sound quality is performed by changing the low frequency characteristic of the sound control device 50 by utilizing the action of the port 63 to invert the phase of the sound wave.

Sound wave W emitted from the rear surface of the speaker 62
2 has a phase difference with the sound wave W1 emitted from the front surface of the speaker 62. The sound wave W2 causes the port 63 to resonate, and the phase thereof is inverted to substantially the same phase as the sound wave W1 in the port 63 to form the sound wave W3.
Is emitted from. The sound wave level of the synthetic sound wave W4 formed from the sound waves W1 and W3 having almost the same phase is increased, and the low frequency characteristic is improved. (Hereafter referred to as bass reflex operation)

The low-frequency characteristic of the synthetic sound wave W4 is determined by the housing 6
If the volume of 1 and the area of the front opening 63a of the port 63 are made constant, the change can be made based on the resonance frequency of the port 63 determined by the length of the port 63.

FIG. 7 is a sound pressure frequency characteristic diagram of a conventional sound control device. (A), (b), (c) figures show the characteristics when the sound switch is in A mode, B mode, and C mode, respectively. Regarding the frequency characteristics in each mode, the clear feeling of natural low and high frequencies is emphasized in (a), the midrange is emphasized according to vocals in (b), and the beat in (c). The low and high frequencies are emphasized to match the tonal music.

As described above, in the conventional sound control device 50, the sound quality is changed by the equalizer section 56 of the sound control means 52 and the speaker unit 54 having the port 63. Therefore, the sound quality corresponding to the sound switch 51 is changed. Is selected.

[0024]

In the conventional sound control device 50, the low range sound quality change is based on the sound switch 51 which selects the sound mode according to the music.
The equalizer section 56 of the sound control means 52 for electrically changing the sound quality and the port 63 of the bass reflex type speaker unit 54 for acoustically changing the low range sound quality.

The conventional sound control device 50 is
Since the length of the port 63 of the speaker unit 54 is fixed, there is a problem that the acoustic change of the low frequency sound quality is limited to one sound mode and cannot be performed in another sound mode.

Therefore, there is a demand for a sound control device capable of finely and easily changing the low frequency sound quality for each sound mode.

The present invention has been made to solve such a problem, and an object thereof is to provide a sound control device capable of finely and easily changing the low-frequency sound quality for each sound mode.

[0028]

In order to solve the above problems, a sound control device according to the present invention is provided with a motor-driven port cover for adjusting the length of a port in a bass reflex type speaker unit, and drives the port cover. It is characterized by comprising a port length control means for controlling.

In the sound control device according to the present invention, the port length control means sets the target position setting means for setting the target position of the port cover based on the selection signal of the sound switch, and the signal from the target position setting means. Port cover control means comprising a computing means for computing the deviation of the signal from the position signal detecting means for detecting the position of the port cover, and a drive control means for driving and controlling the port cover based on the deviation signal of the computing means. It is characterized by having.

[0030]

The sound control device according to the present invention is
Since the bass reflex type speaker unit is provided with a motor-driven port cover for adjusting the port length, and a port length control means for controlling the driving of the port cover is provided.
The port length can be changed finely and easily based on the sound switch.

In the sound control device according to the present invention, the port length control means sets the target position setting means for setting the target position of the port cover based on the selection signal of the sound switch, and the signal from the target position setting means. Port cover control means comprising a computing means for computing the deviation of the signal from the position signal detecting means for detecting the position of the port cover, and a drive control means for driving and controlling the port cover based on the deviation signal of the computing means. Since, the change of the port length can be set to the target position based on the sound switch.

[0032]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall block diagram of a sound control device according to the present invention. In FIG. 1, the sound control device 1 includes a sound switch 2, a sound control means 3, a port length control means 4, and a speaker unit 5.

The sound switch 2 is composed of, for example, a slide switch and has sound modes A, B, and
C and D are selected and selection signals A1, B1, C1 and D1 are provided to the sound control means 3.

The sound control means 3 comprises a sound mode determination control means 6, an equalizer section 7, and an amplification section 8. Since the basic configuration and operation of the sound control means 3 are the same as those of the conventional technique (sound control means 52 in FIG. 5), description thereof will be omitted.

The housing 13 of the speaker unit 5 is made of, for example, a hard synthetic resin material, and the speaker 14 is provided on the inner front wall.
Also, like the case 13, the port 1 made of a hard synthetic resin material
5, a port hole 16 and a port cover 17.

The length of the port 15 changes depending on the position where the port cover 17 closes the port hole 16, and the low frequency band based on the bass reflex operation has a long port 15 (the port cover 17 closes the port hole 16 more. (When the port 15 is in the state), the port 15 becomes narrower when the port 15 is short.

Sensor 19 provided in speaker unit 5
Is composed of, for example, a differential transformer consisting of a primary coil, a secondary coil, and a core.
It is generated by a transmitter (not shown) and supplied.

By configuring the core to move in conjunction with the port cover 17, the displacement of the port cover 17 can be detected as a change in the inductance of the coil, that is, a change in the analog voltage of the secondary coil. The secondary coil of the differential transformer generates an analog voltage based on the position of the port cover 17, and outputs the position information signal S _PI to the port length control means 4.
To provide.

The sensor may be a magnetic Hall element or the like. Further, for example, an optical sensor such as a photo interrupter is provided, and the port cover 17
The position of can also be detected digitally.

The feed mechanism (not shown) of the port cover 17 is provided with, for example, a rack and pinion mechanism and a DC servo motor 18, and converts the rotational movement of the motor 18 into a forward and backward linear movement along the port 15. The motor 18
Can also use a stepper motor.

The port length control means 4 calculates the deviation between the target signal corresponding to the selection signals A1, B1, C1 and D1 of the sound switch 2 and the position signal based on the position information signal S _PI of the port cover 17 from the sensor 19. A motor drive signal V _M for calculating and moving the port cover 17 to a target position is generated based on the deviation signal and provided to the motor 18.

FIG. 2 is a block diagram of the essential parts of the port length control means of the sound control device according to the present invention. In FIG. 2, the port length control means 4 is, for example, RO
It is configured based on a memory such as M, has a calculation function and a processing function, and includes a port cover control unit 20, a driving unit 21, and a position signal detecting unit 22.

Further, the port cover control means 20 comprises a target position setting means 23, a calculation means 24, and a drive control means 25.

The target position setting means 23 stores the selection signals A1, B1 and C from the sound switch 2 in advance in the ROM, for example.
Target position data corresponding to 1 and D1 are set, and when the selection signals A1, B1, C1 and D1 are input, the corresponding target position signal S _MP is provided to the calculating means 24.

The calculating means 24 is composed of, for example, a subtracter having a subtracting function, calculates the deviation between the target position signal S _MP and the position signal S _PO supplied from the position signal detecting means 22, and outputs the deviation signal ΔS (= providing S _MP -S _PO) to the drive control unit 25.

The drive control means 25 sets motor control data corresponding to the deviation signal ΔS in advance in the ROM, for example, and determines whether the deviation of the deviation signal ΔS is positive or negative. For example, when the deviation is positive (ΔS> 0). Is the forward rotation control of the motor 18, the reverse rotation control of the motor 18 when the deviation is negative (ΔS <0), and the deviation is 0 (ΔS = 0), that is, when the port cover 17 is at the target position. A motor control signal V _O for performing rotation stop control is provided to the drive means 21.

The driving means 21 is composed of a switching element, for example, a bridge circuit composed of four FETs (field effect transistors), and drives and controls the FETs (field effect transistors) by the motor control signal V _O from the drive control means 25. , A motor drive signal V for rotating or stopping the motor 18 provided in the speaker unit 5 in either forward or reverse directions
Output _M to the motor 18.

The position signal detecting means 22 is provided with an A / D converting means and converts the position information signal S _PI of the analog voltage from the port cover 17 detected by the sensor 19 provided in the speaker unit 5 into a digital signal. _PO is the calculation means 2
4 to provide.

As described above, the port length control means 4 controls the sound mode selection signals A1, B1,
Corresponding to C1 and D1, port cover 1 at the target position
Motor drive control for moving 7 is performed.

FIG. 3 shows a low frequency sound pressure frequency characteristic diagram of the sound control device according to the present invention. In FIG.
The sound control device 1 corresponds to the sound modes A, B, C and D of the sound switch 2, and shows the tendency of the low frequency characteristics when the position of the port cover 17 is moved and the length of the port 15 is changed. .

A shows the characteristic when the length of the port 15 is long (the state where the port cover 17 closes the port hole 16 to the maximum), and thereafter, the characteristic becomes B, as the port length 15 becomes shorter.
Transition to C and D.

FIG. 4 shows a sound pressure frequency characteristic diagram of the sound control device according to the present invention. In FIG. 4, the sound control device 1 has sound modes A, B,
Corresponding to the port length based on C and D, the port resonance frequency f _op and the speaker resonance frequency f _oc change, and the low frequency band (the left shoulder portion of the curve) also changes.

In the A mode, 35 Hz to 1 Hz so that a sense of depth and afterglow can be felt according to the music such as classical music.
Reproduces wideband frequency characteristics up to 8 KHz. Also, B
The mode aims to represent the naturalness in the low range and the clear feeling in the high range. Furthermore, in C mode, the midrange is emphasized to express vocals suitable for Young Pops. Further, in the C mode, a crisp, energetic low tone and a rock-like punching force are emphasized in the first high range.

In this way, by moving the length of the port 15 of the speaker unit 5 in correspondence with the sound switch 2, bass reflex operation is caused at different frequencies for each of the sound modes A, B, C and D. In particular, the low frequency characteristic can be improved.

[0055]

As described above, in the sound control device according to the present invention, the bass reflex type speaker unit is provided with the motor driven port cover for adjusting the port length, and the port length for controlling the driving of the port cover is provided. Since the control unit is provided and the port length can be changed finely and easily based on the sound switch, it is possible to obtain the sound quality of the frequency characteristic according to the sound mode.

In the sound control device according to the present invention, the port length control means sets the target position setting means for setting the target position of the port cover based on the selection signal of the sound switch, and the signal from the target position setting means. Port cover control means comprising a computing means for computing the deviation of the signal from the position signal detecting means for detecting the position of the port cover, and a drive control means for driving and controlling the port cover based on the deviation signal of the computing means. Since the change of the port cover position is set to the target position based on the sound switch, it is possible to obtain the sound quality of the frequency characteristic according to the sound mode.

Therefore, it is possible to provide a sound control device which easily changes the frequency characteristic according to the selected position of the sound switch for setting the sound mode and acoustically controls the sound quality.

[Brief description of drawings]

FIG. 1 is an overall block configuration diagram of a sound control device according to the present invention.

FIG. 2 is a block diagram of the essential parts of the port length control means of the sound control device according to the present invention.

FIG. 3 is a low frequency sound pressure frequency characteristic diagram of the sound control device according to the present invention.

FIG. 4 is a sound pressure frequency characteristic diagram of the sound control device according to the present invention.

FIG. 5 is a block configuration diagram of a conventional sound control device.

FIG. 6 is a sectional view of a speaker unit of a conventional sound control device.

FIG. 7 is a sound pressure frequency characteristic diagram of a conventional sound control device.

[Explanation of symbols]

1 ... Sound control device, 2 ... Sound switch, 3 sound control means, 4 ... Port length control means, 5 ...
Speaker unit, 6 sound mode determination control means, 7
... equalizer section, 8 ... amplification section, 9 ... buffer, 10 ... low range circuit section, 11 ... middle range circuit section, 12 ... high range circuit section, 13 ... housing, 14 ... speaker, 15 ... port, 16
… Port hole, 17… Port cover, 18… Motor, 19
... sensor, 20 ... port cover control means, 21 ... drive means, 22 ... position signal detection means, 23 ... target position setting means, 24 ... calculation means, 25 ... drive control means, A, B,
C, D ... Sound mode, A1, B1, C1, D1 ... Selection signal, T1, T2, M1, M2, K1, K2 ... Gain control signal, S1, S2, S3, S4, S5, S6 ... Audio signal, S _PI ... position information signal, S _PO ... position signal, S _MP ... target position signal, [Delta] S ... deviation signal, V _O ... motor control signal, V _M
… Motor drive signal.

Claims (2)

[Claims] 1. A sound control device comprising a sound switch, sound control means for electrically changing the sound quality based on a selection signal of the sound switch, and a bass reflex type speaker unit for acoustically changing the sound quality. A sound control device characterized in that the bass reflex speaker unit is provided with a motor-driven port cover for adjusting the length of the port, and a port length control means for controlling the driving of the port cover. 2. The port length control means sets a target position of the port cover based on a selection signal of the sound switch, a signal from the target position setting means and a position of the port cover. And a port cover control means that includes a drive control means that drives and controls the port cover based on the deviation signal of the arithmetic means. The sound control device according to claim 1, wherein: