JP3447888B2 - Method and apparatus for measuring speaker parameters - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker parameter measuring method and a measuring apparatus, and more specifically, a speaker parameter measuring method and a measuring method capable of measuring a load parameter which is difficult to measure in an actual use state. Regarding the device.

[0002]

2. Description of the Related Art Usually, a speaker unit is used by being attached to a closed wooden box (speaker box or enclosure) having a predetermined volume.
In this case, it is known that the shape of the speaker box has a great influence on the movement of the speaker diaphragm, and is an important parameter in the design of the speaker unit.

Here, load parameters (load resistance, load mass, load capacity) representing the acoustic load state of the speaker unit are important parameters in designing the speaker unit. Therefore, by obtaining the load parameter in the attached state, it becomes possible to make a design change so as to match the attached state.

Therefore, in the case of designing such a speaker unit, the volume can be easily calculated in the case of a simple shape such as a wooden box, so that it is easy to find the parameter in the actual use state and the load parameter. (Difference between the seal small parameter in the free sound field and the parameter in the actual use condition) can be easily calculated.

The seal small parameter is a parameter of a speaker unit according to a paper published by two members, AN THIELE and RICHARD H. SMALL.

That is, the seal small parameter is
The impedance of the speaker unit is a measured value obtained by constant voltage or constant current measurement, and a calculated parameter, which represents the basic performance of the speaker unit.

[0007]

However, it is difficult to calculate the load parameters when the volume of the speaker unit mounting portion is complicated or the volume cannot be clearly determined due to insufficient sealing. become. In this case, it is also difficult to optimally design the speaker unit.

The present invention has been made in view of the above problems, and its purpose is to calculate load parameters because the volume in an actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion. It is an object of the present invention to provide a speaker parameter measuring method and a measuring device capable of obtaining a load parameter even when it is difficult.

[0009]

The present invention, which is means for solving the problems, is basically as described in (1) to (4) below.

(1) According to the first aspect of the invention, a speaker unit whose seal small parameter has been measured in a free sound field is mounted in an actual use state, impedance characteristics of the speaker unit are measured, and the measured impedance characteristic and the measured impedance characteristic are stored in advance. A speaker parameter measuring method is characterized in that the load mass, load capacity, and load resistance of a speaker unit in an actual use state are calculated from the obtained seal small parameter.

In the speaker parameter measuring method according to the first aspect of the present invention, the seal small parameter of the speaker unit in a free sound field is measured in advance. As a result of measuring the impedance characteristic by mounting the speaker unit in an actual use state. The load mass, load capacity, and load resistance of the speaker unit in actual use are calculated from and the seal small parameter.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and the actual use are used. The load parameter can be obtained from the impedance characteristic in the state.

(2) A second aspect of the present invention is an impedance characteristic measuring means for mounting a speaker unit whose seal small parameter is measured in a free sound field in advance in an actual use state to measure an impedance characteristic, and the measured impedance characteristic. And a load parameter measuring means for calculating a load mass, a load capacity and a load resistance of the speaker unit in an actual use state from the seal small parameter obtained in advance and a speaker parameter measuring device. .

In the speaker parameter measuring device of the second invention, the seal small parameter of the speaker unit in the free sound field is measured in advance, and the impedance characteristic is measured by mounting this speaker unit in the actual use state. The load mass, load capacity, and load resistance of the speaker unit in actual use are calculated from the results and the seal small parameters.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and the actual use are used. The load parameter can be obtained from the impedance characteristic in the state.

(3) A third aspect of the present invention is an impedance characteristic measuring means for mounting a speaker unit whose seal small parameter is measured in a free sound field in advance in an actual use state and measuring impedance characteristics, and the measured impedance characteristic. The minimum resonance frequency, total Q, and impedance at the minimum resonance frequency are obtained from the actual use parameters, and the load mass, load capacity, and load resistance of the speaker unit in the actual use state are calculated from the actual use parameters and the seal small parameters obtained in advance. And a load parameter measuring means for calculating.

In the speaker parameter measuring device according to the third aspect of the present invention, the seal small parameter of the speaker unit in a free sound field is measured in advance, and the impedance characteristic is measured by mounting this speaker unit in an actual use state. Read the actual use parameters from the result,
The load parameter is calculated by performing calculation from the actual use parameter and the seal small parameter.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and the actual seal small parameter are used. The load parameter can be obtained from the actual use parameter read from the impedance characteristic in the use state.

(4) A fourth aspect of the present invention is an impedance characteristic measuring means for mounting a speaker unit whose seal small parameter is measured in a free sound field in advance in an actual use state to measure the impedance characteristic, and the measured impedance characteristic. From the first actual use parameter calculating means for obtaining the lowest resonance frequency, the total Q, and the impedance at the lowest resonance frequency as the first actual use parameter, and the first actual use parameter and the seal small parameter in the actual use state. Second actual use parameter calculating means for calculating the mass of the entire vibration system, the compliance of the entire vibration system, and the mechanical resistance of the entire vibration system as the second actual use parameter, the second actual use parameter, and the seal small parameter. To the load mass and load capacity of the speaker unit in actual use And load parameter-calculating means for calculating a micro load resistor, a measuring device speaker parameters comprising the.

In the speaker parameter measuring device according to the fourth aspect of the present invention, the seal small parameter of the speaker unit in a free sound field is measured in advance, and the impedance characteristic is measured by mounting this speaker unit in an actual use state. From the results, the lowest resonance frequency, the total Q, and the impedance at the lowest resonance frequency are obtained as the first actual use parameters.

From the first actual use parameter and the seal small parameter, the mass of the entire vibration system in the actual use state, the compliance of the entire vibration system, and the mechanical resistance of the entire vibration system are used as the second actual use parameters. calculate.

Further, the load mass, the load capacity and the load resistance of the speaker unit in the actual use state are calculated from the second actual use parameter and the seal small parameter.

Therefore, even if it is difficult to calculate the load parameters because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameters measured in advance and the actual use are used. The load parameter can be obtained from the first actual use parameter read from the impedance characteristic in the state and the calculated second actual use parameter.

(5) Another aspect of the invention is that the seal small parameter in a free sound field is measured in advance, and the impedance characteristic is measured in advance for a speaker unit mounted in an actual use state and the impedance characteristic is measured. And a load parameter measuring means for calculating a load mass, a load capacity and a load resistance of the speaker unit in an actual use state from the seal small parameter.

In the speaker parameter measuring device of the present invention, the seal small parameter of the speaker unit in the free sound field and the impedance characteristic in the actual use state are measured in advance. The load mass, load capacity, and load resistance of the speaker unit in actual use are calculated from the small parameters.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and the actual use are used. The load parameter can be obtained from the impedance characteristic in the state.

In this case, it is preferable that the load parameter measuring means is composed of the actually used parameter calculating means and the load parameter calculating means as described in the third invention.

Further, the actual use parameter calculating means can be constituted by the first actual use parameter calculating means and the second actual use parameter calculating means, as described in the above-mentioned fourth invention.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a flow chart showing a flow of processing of a speaker parameter measuring method of the present embodiment, and FIG. 2 is a block diagram showing a configuration of a speaker parameter measuring device of the present embodiment.

<Structure of Speaker Parameter Measuring Device>
First, the configuration of the speaker parameter measuring device will be described with reference to FIG.

The actual use environment 1 is an environment (actual use state) in which the speaker unit to be measured is actually used,
For example, the mounting position of a door or the like in an automobile, the mounting position of a wall surface of a room, or the like is applicable. Or, it means an environment equivalent to the environment actually used.

It is assumed that the speaker unit 10 is an object to be measured whose load parameter is finally measured according to this embodiment, and the seal small parameter 20 is measured in advance. Therefore, the seal small parameter 20 is stored as data in a predetermined location.
Alternatively, the operator may input the load parameter when measuring it.

The measurement / calculation unit 30 includes the speaker unit 10.
The load mass, the load capacity, and the load resistance of the speaker unit in the actual use state are calculated from the result of measuring the impedance characteristics by mounting in the actual use environment 1. The impedance characteristic measuring unit 31 and the load parameter measuring unit 3
It consists of two.

Further, the load parameter measuring unit 32 calculates the actual use parameter from the impedance characteristic and the seal small parameter, and the actual use parameter calculation unit 33.
And the load parameter calculation unit 34 based on the actual use parameters and the seal small parameters.

The impedance characteristic measuring section 31 is a measuring means for measuring an impedance frequency characteristic (impedance curve: hereinafter simply referred to as impedance characteristic) which is a characteristic of impedance varying with the frequency of the speaker unit 10 in the actual use environment 1. is there.

The actual use parameter calculation unit 33 obtains the lowest resonance frequency, the total Q, and the impedance at the lowest resonance frequency as the first actual use parameters from the impedance characteristics, and determines the first actual use parameters and the seal small parameters. From the above calculation, the mass of the entire vibration system, the compliance of the entire vibration system, and the mechanical resistance of the entire vibration system in the actual use state are calculated as the second actual use parameters.

The minimum resonance frequency and its impedance can be read from the impedance characteristics.
Further, the total Q can be calculated by referring to the frequency at which the impedance value is maximum and the frequency at which the impedance is 1 / √2 of the maximum value.

The load parameter calculating section 34 is adapted to calculate the load mass, load capacity and load resistance of the speaker unit in the actual use state from the second actual use parameter and the seal small parameter.

<Processing Procedure of Speaker Parameter Measuring Method> With respect to the operation of the speaker parameter measuring apparatus configured as described above and the processing procedure of the speaker parameter measuring method, the principle operation will be described with reference to the flowchart of FIG. This will be described below.

(1) Installation of speaker unit (Fig. 1
S1): The seal small parameter is measured in advance for the speaker unit whose load parameter is to be obtained. Then, this speaker unit is installed in the actual use environment 1.

This actual use environment 1 is an environment in which the speaker unit 10 to be measured is actually used (a mounting position of a door or the like in an automobile, a wall mounting position in a room, etc.), or an environment equivalent to the actual use environment. is there.

Therefore, it is preferable that the mounting method is also adapted to the actual use state. For example, in the case of mounting using screws, it is preferable that the material of the screws to be used, the tightening torque and the like are also taken into consideration in consideration of the actual use state. Further, the conditions such as the grill attached to the front surface of the speaker unit 10 are set to be equal in consideration of the actual use state.

(2) Measurement of impedance characteristics (Fig. 1S
2): Impedance characteristic measuring unit 31 is in the actual use environment 1
The impedance characteristic that changes depending on the frequency of the speaker unit 10 is measured. The measured impedance characteristics are stored in a predetermined storage means as needed, and are supplied to the actual use parameter calculation unit 33.

(3) Measurement and calculation of actual use parameters (FIG. 1S3): The actual use parameter calculation unit 33 determines the first actual use parameters such as the minimum resonance frequency, the total Q, and the impedance at the minimum resonance frequency from the above impedance characteristics. Ask for.

Here, the lowest resonance frequency and the impedance at the lowest resonance frequency can be read from the impedance characteristics. Regarding the total Q, referring to the impedance characteristics, the frequency at which the impedance is maximum and the impedance is 1 / √2 of the maximum value
It is possible to obtain from the frequency, the minimum value of the impedance characteristic, and the maximum value of the impedance by a known calculation method.

From the first actual use parameter and the seal small parameter, the mass of the entire vibration system in the actual use state, the compliance of the entire vibration system, and the mechanical resistance of the entire vibration system are used as the second actual use parameters. calculate.

(4) Calculation of load parameters (FIG. 1S
4): The load parameter calculation unit 34 calculates the load mass, the load capacity, and the load resistance of the speaker unit in the actual use state from the second actual use parameter and the seal small parameter.

By the above processing, even if it is difficult to calculate the load parameters by the conventional method because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the measurement is performed in advance. It becomes possible to obtain the load parameter from the seal small parameter thus obtained and the impedance characteristic in the actual use state.

<Details of Measurement and Calculation of Each Parameter> Here, details of the measurement and calculation of each parameter described above will be described. It should be noted that the processing method described here is merely an example, and can be replaced by a substantially equivalent calculation.

The seal small parameter of the speaker unit in the free sound field is defined as follows. A: Force coefficient R _E : DC resistance F _S0 : Minimum resonance frequency M _MS0 : Mass of the entire vibration system C _MS0 : Compliance of the entire vibration system R _MS0 : Mechanical resistance of the entire vibration system Therefore, the speaker unit 10 is shown here. It is assumed that such a seal small parameter is measured and stored in a predetermined place (memory device or the like).
Or, the seal small parameter measured in advance,
The operator may input it when measuring the load parameter.

The parameters (actual use parameters) of the speaker unit in the actual use state are defined as follows. F _S1 : Minimum resonance frequency M _MS1 : Mass of entire vibration system C _MS1 : Compliance of entire vibration system R _MS1 : Mechanical resistance of entire vibration system Q _TS1 : Total Q Z _O1 : Impedance at minimum resonance frequency F _S1 The above seal The small parameter can be directly measured in advance in a free sound field environment. Further, in the above-mentioned actual use parameters, F _S1 and Z _O1 can be read from the impedance characteristic.

Further, Q _TS1 can be obtained from the impedance characteristic by a well-known calculation method. Therefore, F _S1 , Q _TS1 , and Z _O1 are read or obtained from the impedance characteristics as the first actual use parameters.

Then, using the above-mentioned first actual use parameter and the above-mentioned seal small parameter, M
_MS1 , C _MS1 , and R _MS1 are calculated as the second actually used parameters.

Here, the lowest resonance frequency F _{S1 in} actual use is
Because the impedance Z _O1 located on the real axis at, and _{Z O1 = R E + (A} 2 / R MS1) ... (1).

[0055] Therefore, mechanical resistance R _MS1 of the entire vibration system of the actual use state, R _MS1 = a _{^{(A 2 / (Z O1 -R}} E)) ... (2).

The total Q in the actual use state is Q.
_TS1 becomes Q _TS1 = (2πF _S1 · M _MS1 ) / (R _MS1 + (A ² / R _E )) (3).

[0057] Here, (3) Substituting (2) into _{equation, Q TS1 = (2πF S1 ·} M MS1) / ((A 2 / (Z O1 -R E)) + (A 2 / R E ))… (3) '.

Therefore, the mass M _MS1 of the entire vibration system in the actual use state is M _MS1 = (A ² Q _TS1 / 2πF _S1 ) · (1 / (ZO 1 −R _E ) + 1 / R _E ) ... (4) Becomes

Here, F _S1 = (1 / 2π) · {1 / (M
_MSi・ C _MS1 )} ^1/2 . Therefore, the compliance C _MS1 of the entire vibration system in the actual use state is C _MS1 = 1 / ((2πF _S1 ) ² · M _MS1 ) (5).

By performing such calculation, from the impedance characteristic and the seal small parameter, (2)
The second actually used parameters M _MS1 , C _MS1 , and R _MS1 are obtained from the formula, the formula (3), and the formula (4).

Then, the load parameter calculation unit 34
The load parameter as shown below is calculated with reference to the above seal small parameter and the second actually used parameter.

Load resistance R _MS : R _MS = R _MS1 −R _MS0 (6) from the difference between the actual use state of the mechanical resistance of the entire vibration system and the free sound field.

Load mass M _MS : From the difference between the actual use state of the mass of the entire vibration system and the free sound field, M _MS = M _MS1 −M _MS0 (7)

Load capacity V: Load compliance C _MS is obtained from C _MS1 and C _MS0 as 1 / C _MS1 −1 / C _MS0 = 1 / C _MS (8)

Then, this load compliance C
_MS , air density ρ ₀ , sound velocity C, and diaphragm effective area a
_{Using D} and, V = ρ ₀ · C ² · a _D ² · C _MS (9)

By the above calculation, even when it is difficult to calculate the load parameter by the conventional method, the load parameter can be obtained from the seal small parameter measured in advance and the impedance characteristic in the actual use condition. Become.

The calculation for obtaining M _MS1 in the above may be replaced by the following method. Using R _MS1 calculated from the above formula (1), Z ₁ = ((R _E + A ² / 2R _MS1 ) ² + (A ² / 2R _MS1 )) ^1/2 ... (10 ).

As shown in FIG. 3, assuming that the frequencies at which the impedance becomes Z ₁ are f ₁ and f ₂ , the following formula f ₂ −f ₁ = (R _MS1 ) / (2πM _MS1 ) ... (11 ) Holds.

When M _MS1 is obtained from the equation (11), the above
The same result as Eq. (4) is obtained, and the compliance C of the entire vibration system in the actual operating condition equal to Eq. (5)
_MS1 is required.

By performing the calculation as described above, the second actual use parameters (R _MS1 , M _MS1 , C _MS1 ) are obtained from the first actual use parameters obtained from the impedance characteristics and the seal small parameters obtained in advance. Therefore, it becomes possible to obtain the load parameter even when it is difficult to calculate the load parameter by the conventional method.

<Other Preferred Embodiment Examples>
Besides the above description of the embodiment, the following modified configuration examples are also possible.

The actual use parameter calculation unit 33 in FIG. 2 in each of the above-described embodiments has the first actual use parameter calculation means for reading the first actual use parameter from the impedance characteristic and the first actual use parameter. A second actual use parameter calculating means for calculating a second actual use parameter from the seal small parameter is considered to be included.

Therefore, as shown in FIG. 4, the first actual use parameter calculator 33 for reading the first actual use parameter.
A and the second actual use parameter calculation unit 33B that calculates the second actual use parameter configure the actual use parameter calculation unit 33.

In each of the above embodiments, only the impedance characteristic may be measured in the vicinity of the speaker unit 10 in order to accurately measure the impedance and to reduce the size of the impedance measuring portion.
In this case, it is possible to perform the calculation from the impedance characteristic at another remote place. Therefore, the impedance characteristic measuring unit 31 and the other portion (the load parameter measuring unit 32) can be configured separately.

Therefore, as shown in FIG. 5, a configuration may be considered in which the impedance characteristic measured by the impedance characteristic measuring section is transmitted to the load parameter measuring section 32 which is separated in time or distance.

In this case, the impedance characteristic is transmitted by using transmission using radio waves or infrared rays, or by connecting devices (impedance characteristic measuring section 31 and load parameter measuring section 32) which are separately configured. Is possible.

<Effects Obtained by Embodiments: Comparison with Conventional Examples> As described above, the impedance characteristics are measured by mounting the speaker unit in an actually used state, and the result and the seal small parameter measured in advance are measured. The following effects can be obtained by calculating the load parameters in the actual use state from the above.

Even when it is difficult to calculate the load parameters by the conventional method because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameters measured in advance and the actual seal small parameters are used. It becomes possible to obtain the load parameter from the calculation with the impedance characteristic in the use state.

Since the measurement performed on the speaker unit in the actual use state is only the impedance characteristic, the actual measurement work itself can be performed extremely quickly and easily. Therefore, as long as the impedance characteristic can be measured, it can be implemented in any environment.

Since other parameters are read and calculated from the impedance characteristic, the other parameters can be easily and accurately obtained. Since calculations other than impedance measurement are calculations, the entire process can be performed at high speed and the device can be downsized.

[0081]

As described above, according to the present invention, the following effects can be obtained. (1) In the speaker parameter measuring method according to the first aspect of the invention, the speaker in the actual use state is selected from the result of measuring the impedance characteristics by mounting the speaker unit whose seal small parameter has been measured in advance in the actual use state and the seal small parameter. The load parameters of the unit are calculated.

Therefore, even if it is difficult to calculate the load parameters because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameters measured in advance and the actual use are used. The load parameter can be obtained from the impedance characteristic in the state.

(2) In the loudspeaker parameter measuring device of the second invention, the loudspeaker unit whose seal small parameter has been measured in advance is mounted in a practical use state, and the impedance characteristic is measured and the seal small parameter is actually used. The load mass, load capacity, and load resistance of the speaker unit in this state are calculated.

Therefore, even if it is difficult to calculate the load parameters because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameters measured in advance and the actual use are used. The load parameter can be obtained from the impedance characteristic in the state.

(3) In the speaker parameter measuring device of the third aspect of the invention, the speaker unit whose seal small parameter has been measured in advance is mounted in an actual use state, and the actual use parameter is read from the result of impedance characteristic measurement. The load parameter in the actual use state is calculated from the actual use parameter and the seal small parameter.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and The load parameter can be obtained from the actual use parameter read from the impedance characteristic in the use state.

(4) In the speaker parameter measuring device of the fourth aspect of the invention, the speaker unit whose seal small parameter has been measured in advance is attached in an actual use state and the first actual use parameter is determined from the result of impedance characteristic measurement. The second actual use parameter is read out and calculated from the first actual use parameter, and the load parameter in the actual use state is calculated from the second actual use parameter and the seal small parameter.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and the actual use may be used. The load parameter can be obtained from the first actual use parameter read from the impedance characteristic in the state and the calculated second actual use parameter.

Therefore, even if it is difficult to calculate the load parameter because the volume in the actual use state cannot be clearly defined due to the shape and structure of the speaker unit mounting portion, the seal small parameter measured in advance and the actual use may be used. The load parameter can be obtained from the first actual use parameter read from the impedance characteristic in the state and the calculated second actual use parameter.

[Brief description of drawings]

FIG. 1 is a flowchart showing a processing procedure of speaker parameter measurement according to a first embodiment of this invention.

FIG. 2 is a block diagram showing a configuration of a speaker parameter measuring device according to the first embodiment of the present invention.

FIG. 3 is an impedance characteristic diagram showing a relationship between frequency and impedance in the speaker parameter measuring method according to the embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a speaker parameter measuring device according to a second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a speaker parameter measuring device according to a third embodiment of the present invention.

[Explanation of symbols]

1 Actual use environment 10 speakers 20 Seal Small Parameter 30 Measurement calculation section 31 Impedance characteristics measurement unit 32 Load parameter measurement unit 33 Actual use parameter calculation unit 33A First actual use parameter calculation unit 33B Second actual use parameter calculation unit 34 Load Parameter Calculation Unit

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04R 29/00 310 G01R 27/02 G01R 31/00

Claims (4)

(57) [Claims] 1. A speaker unit in which a seal small parameter is measured in a free sound field in advance is mounted in an actual use state, impedance characteristics of the speaker unit are measured, and the measured impedance characteristic and the seal small parameter obtained in advance are used. A method for measuring speaker parameters, characterized in that the load mass, load capacity, and load resistance of the speaker unit in actual use are calculated from. 2. Impedance characteristic measuring means for measuring impedance characteristics by mounting a speaker unit in which a seal small parameter is measured in a free sound field in an actual use state, and the measured impedance characteristic and a seal small obtained in advance. A speaker parameter measuring device, comprising: load parameter measuring means for calculating the load mass, load capacity, and load resistance of the speaker unit in actual use from the parameter. 3. Impedance characteristic measuring means for measuring the impedance characteristic by mounting a speaker unit whose seal small parameter is measured in a free sound field in actual use, and a minimum resonance frequency and a total Q from the measured impedance characteristic. And the impedance at the lowest resonance frequency as an actual use parameter, and load parameter measuring means for calculating the load mass, the load capacity and the load resistance of the speaker unit in the actual use condition from the actual use parameter and the seal small parameter obtained in advance. And a speaker parameter measuring device. 4. Impedance characteristic measuring means for measuring the impedance characteristic by mounting a speaker unit whose seal small parameter is measured in a free sound field in actual use, and a minimum resonance frequency and a total Q from the measured impedance characteristic. And the impedance at the lowest resonance frequency
From the first actual use parameter and the seal small parameter, the mass of the entire vibration system in the actual use state, the compliance of the entire vibration system, and the machine of the entire vibration system. A second actual use parameter calculating means for calculating resistance as a second actual use parameter, and a load mass, a load capacity, and a load resistance of the speaker unit in an actual use state from the second actual use parameter and the seal small parameter. And a load parameter calculating unit for calculating the parameter.