JP2007060648A5

JP2007060648A5 -

Info

Publication number: JP2007060648A5
Application number: JP2006206248A
Authority: JP
Filing date: 2006-07-28
Publication date: 2008-04-24
Anticipated expiration: 2026-07-28

Claims

A speaker including a diaphragm, a support system member composed of an edge and a damper for supporting the diaphragm so as to vibrate, and a voice coil that generates a driving force that enables the diaphragm to vibrate ;
A fixed parameter modeling vibration displacement characteristics indicating the stiffness of the support system member with respect to vibration displacement of the diaphragm, and a force coefficient acting on the voice coil and indicating a force coefficient with respect to the vibration displacement of the diaphragm and at least including filter coefficients and parameters of the displacement characteristics fixed modeled, based on the set filter coefficients to cancel the non-linear components of each parameter, full I over-forward the electric signal to be inputted to the loudspeaker A feedforward processing unit to process;
Detecting the vibration of the diaphragm, an electric signal related to the vibration, and a feedback processing section for feedback processing on the electric signal to be inputted to the loudspeaker,
The feedback processing unit, so as to cancel the change in the vibration displacement characteristic indicating the stiffness of the support system member, and the frequency characteristics related to the vibration of the vibration plate so as to have a desired frequency characteristic, an electrical signal concerning the vibration A speaker device that performs feedback processing.

The feedback processing unit
An ideal filter that receives an electrical signal to be input to the speaker and converts the frequency characteristic of the electrical signal to the desired frequency characteristic;
A sensor for detecting vibration of the vibrating plate,
A first adder that takes a difference between an electric signal indicating a desired frequency characteristic converted by the ideal filter and an electric signal related to the vibration detected by the sensor, and outputs the difference electric signal as an error signal; ,
The speaker device according to claim 1, further comprising: a second adder that adds the electrical signal processed in the feedforward processing unit and the error signal and outputs the sum to the speaker.

The feedforward processing unit
And inputting an electric signal to be inputted to the loudspeaker, on the basis of the previous SL filter coefficients, a removal filter for processing those electrical signals,
And inputting an electric signal to be inputted to the loudspeaker, and a linear filter for generating an electrical signal indicative of the vibration displacement when the diaphragm is assumed to vibrate in a linear,
The speaker device according to claim 2 , wherein the removal filter refers to an electric signal indicating a vibration displacement generated in the linear filter.

A power amplifier provided between the second adder and the speaker and further amplifying a gain of an electric signal to be input to the speaker;
4. The speaker according to claim 3 , wherein the filter coefficient in the removal filter, the filter coefficient in the ideal filter, and the filter coefficient in the linear filter are filter coefficients multiplied by a reciprocal of a gain amplified in the power amplifier . apparatus.

Electrical signal detected in the sensor is an electric signal which indicates the vibration displacement of the vibrating plate,
The speaker device according to claim 2 , wherein the feedforward processing unit refers to an electric signal indicating a vibration displacement detected by the sensor.

Provided in the previous stage of the feedforward processing unit, an electric signal to be input to the speaker is input, and processing is performed based on a filter coefficient obtained by dividing the desired frequency characteristic by a characteristic related to vibration of the speaker. The speaker device according to claim 2, further comprising a front-stage filter.

The speaker device according to claim 2, further comprising a limiter that limits a level of the electric signal so that an electric signal of a predetermined level or more is not input to the speaker.

A power amplifier provided between the second adder and the speaker and further amplifying a gain of an electric signal to be input to the speaker;
The speaker device according to claim 2, wherein the filter coefficient in the feedforward processing unit and the filter coefficient in the ideal filter are filter coefficients multiplied by a reciprocal of a gain amplified in the power amplifier .

The speaker device according to claim 1, wherein the feedforward processing unit is provided in a front stage of the speaker and is provided in a feedback loop formed by the feedback processing unit.

The feedback processing unit
An ideal filter that receives an electrical signal to be input to the speaker and converts the frequency characteristic of the electrical signal to the desired frequency characteristic;
A sensor for detecting vibration of the vibrating plate,
A first adder that takes a difference between an electric signal indicating a desired frequency characteristic converted by the ideal filter and an electric signal related to the vibration detected by the sensor, and outputs the difference electric signal as an error signal; ,
By adding the said electrical signal an error signal to be inputted to the loudspeaker, and a second adder for outputting the feedforward processing section,
The feedforward processing section, the electric signal output from the second adder and off I over-forward process output to the speaker, the speaker device according to claim 1.

Provided between the second adder and the feedforward processing unit, the gain of the electric signal to be input to the speaker is inclined with a slope of -6 dB / oct or less in a frequency band of the first frequency or less. A low-pass filter having a filter coefficient indicating characteristics;
Said first frequency, wherein said a gain crossover frequency or higher frequency indicated by an open-loop transfer characteristic of the feedback loop formed by the feedback processing unit, a speaker apparatus according to claim 1 0.

A high-pass filter that is provided before the feedforward processing unit and has a filter coefficient showing a characteristic that a gain of an electric signal to be input to the speaker is inclined with a gradient of 6 dB / oct or more in a frequency band of a second frequency or lower. Further comprising
Said second frequency, wherein the a gain crossover frequency or higher frequency indicated by an open-loop transfer characteristic of the feedback loop formed by the feedback processing unit, a speaker apparatus according to claim 1 0.

Provided between the second adder and the feedforward processing unit, the gain of the electric signal to be input to the speaker is inclined with a slope of -6 dB / oct or less in a frequency band of the first frequency or less. A low-pass filter having a filter coefficient indicating characteristics;
A high-pass filter that is provided before the feedforward processing unit and has a filter coefficient showing a characteristic that a gain of an electric signal to be input to the speaker is inclined with a gradient of 6 dB / oct or more in a frequency band of a second frequency or lower. And further comprising
Said first and second frequencies, wherein said a gain crossover frequency or higher frequency indicated by an open-loop transfer characteristic of the feedback loop formed by the feedback processing unit, a speaker apparatus according to claim 1 0 .

The feedforward processing unit
And inputting an electric signal output from said second adder, on the basis of the previous SL filter coefficients, a removal filter for processing those electrical signals,
And inputting an electric signal output from the second adder, and a linear filter for generating an electrical signal indicative of the vibration displacement when the diaphragm is assumed to vibrate in a linear,
The speaker device according to claim 10 , wherein the removal filter refers to an electric signal indicating a vibration displacement generated in the linear filter.

A power amplifier provided between the feedforward processing unit and the speaker and further amplifying a gain of an electric signal to be input to the speaker;
The filter coefficient of the removal filter, a filter coefficient in the ideal filter, and filter coefficient of the linear filter is a filter coefficient inverse of the gain is multiplied to be amplified in the power amplifier, according to claim 1 4 Speaker device.

Electrical signal detected in the sensor is an electric signal which indicates the vibration displacement of the vibrating plate,
The speaker device according to claim 10 , wherein the feedforward processing unit refers to an electric signal indicating a vibration displacement detected by the sensor.

Based on a filter coefficient that is provided in the preceding stage of the second adder, receives an electrical signal to be input to the speaker, and divides the desired frequency characteristic by a characteristic related to vibration of the speaker. further comprising a speaker apparatus according to claim 1 0 pre-stage filter.

Further comprising a limiter for limiting the level of the electrical signals as electrical signals over a predetermined level to the speaker is not input, the speaker device according to claim 1 0.

A power amplifier provided between the feedforward processing unit and the speaker and further amplifying a gain of an electric signal to be input to the speaker;
Filter coefficients in the filter coefficient and the ideal filter in the feedforward processing section is a filter coefficient inverse of the gain to be amplified is multiplied in the power amplifier, a speaker apparatus according to claim 1 0.

The speaker according to claim 1, wherein the change in the vibration displacement characteristic indicating the stiffness of the support system member is caused by aging of a material constituting the support system member or a creep phenomenon of the material constituting the support system member. apparatus.

The speaker device according to claim 1, wherein a material constituting the support system member is cloth or resin.

Input to a speaker including a diaphragm, a support system member composed of an edge and a damper for supporting the diaphragm so as to vibrate, and a voice coil for generating a driving force that enables the diaphragm to vibrate An integrated circuit for processing electrical signals to be performed,
A fixed parameter modeling vibration displacement characteristics indicating the stiffness of the support system member with respect to vibration displacement of the diaphragm, and a force coefficient acting on the voice coil and indicating a force coefficient with respect to the vibration displacement of the diaphragm and at least including filter coefficients and parameters of the displacement characteristics fixed modeled, based on the set filter coefficients to cancel the non-linear components of each parameter, the electric signal to be inputted to the loudspeaker off I over feedforward processing A feedforward processing unit to perform,
Detecting the vibration of the diaphragm, an electric signal related to the vibration, and a feedback processing section for feedback processing on the electric signal to be inputted to the loudspeaker,
The feedback processing unit, so as to cancel the change in the vibration displacement characteristic indicating the stiffness of the support system member, and the frequency characteristics corresponding to the vibration of the diaphragm such that the desired frequency characteristics, electrical relates the vibration An integrated circuit that feeds back a signal.