JPH0376079B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a horn speaker with improved frequency characteristics and transient characteristics.

In conventional horn speakers, the treble reproduction limit frequency is the resonance (hereinafter referred to as resonance fc) generated by the acoustic capacity of the air chamber in front of the diaphragm and the mass of the diaphragm.
The smaller the acoustic capacity, the higher the treble reproduction limit frequency. For this reason, in order to increase the treble reproduction limit frequency, speakers are designed to narrow the distance between the diaphragm and the equalizer to reduce the stiffness of the air chamber in this area, but when a large input is applied to this speaker, The diaphragm and equalizer may come into contact and destroy the diaphragm. Also,
The above-mentioned resonance fc controls the transient characteristics of the reproduced sound in the high range,
It is causing deterioration.

In addition to resonance fc, there is resonance (hereinafter referred to as resonance fm) caused by the stiffness of the edges and the mass of the diaphragm, and in conventional horn speakers, damping of this resonance fm is insufficient. I can't say it,
This resonance FM is the biggest cause of deterioration of the transient characteristics and frequency characteristics of the speaker.

In addition, in the low frequency range, the diaphragm vibrates as a piston, with the entire diaphragm moving as one, but as the frequency increases, the time required for vibration transmission from the center of the diaphragm to the periphery cannot be ignored, and the diaphragm itself Split vibration begins and an abnormality occurs.

On the other hand, regarding the edge part, resonance of the edge itself occurs in the midrange range, resulting in small peaks and troughs in the midrange due to the sound pressure characteristics, making it impossible to reproduce faithfully.

Furthermore, there are only two types of damping for these resonances in conventional horn speakers: electromagnetic damping using a coil, and acoustic damping using a diaphragm of the aperture area at the throat throat.

Acoustic damping by the aperture at the throat throat is
Increasing the aperture will increase braking, but if the aperture is stopped too much, resonance fc will occur.
Distortion increases in the reproduced sound due to factors such as an increase in the influence of Therefore, there is a limit to the aperture, and there is also a limit to the braking effect of this aperture.

In conventional speakers, there is an upper limit to the acoustic resistance due to throat narrowing, so there is insufficient braking force to suppress resonance FM. Furthermore, if a network or attenuator is used for electromagnetic braking, the braking force will be greatly reduced, resulting in insufficient braking.

As described above, in conventional horn speakers, no effective countermeasures have been taken against these deteriorating factors of damping, resulting in extremely poor frequency characteristics and transient characteristics.

In the aforementioned Utility Model Application Publication No. 51-77131, a sound absorbing material was placed in the center between the equalizer and the dome-shaped diaphragm in order to suppress the split vibration that tends to occur near the center of the diaphragm and to flatten the frequency response. A contacting technique is shown.

However, in this invention, the sound absorbing material is brought into contact with the center of the diaphragm at one point, so it is possible to suppress the split vibration that tends to occur near the center of the diaphragm, but it also resonates at high frequencies, causing new acoustic distortion. There was a problem that could arise.

The present invention has been made based on the above-mentioned viewpoints, and its purpose is to increase the braking force against piston vibration caused by the diaphragm moving as one body, compared to conventional horn speakers, and to improve transient characteristics. To provide a horn speaker which is excellent in sound reproduction, has a high treble reproduction limit frequency, and has good high frequency characteristics.

The above object is to provide a horn-type speaker, characterized in that the entire space between the diaphragm of the diaphragm and the equalizer and between the edge and throat of the diaphragm is filled with a soft porous material.・Achieved by speakers.

With the above configuration, in the horn speaker according to the present invention, a part of the sound wave energy is consumed due to the acoustic resistance of the soft porous material filling the space, so that the front surface of the diaphragm is The acoustic capacity of the space is apparently smaller, the treble reproduction limit frequency becomes higher, and the high frequency characteristics are improved. Furthermore, the acoustic resistance of the porous material improves high-frequency transient characteristics. Furthermore, if the high frequency characteristics remain the same as before, the distance between the diaphragm and the equalizer can be made larger than before, so even if there is a large input that causes a large amplitude on the diaphragm, faithful reproduction can be achieved. It is something that can be done.

Hereinafter, the details of the present invention will be specifically explained with reference to the drawings.

The drawing is a sectional view showing an embodiment of a horn speaker according to the present invention.

In the figure, 1 is a yoke, 2 is a magnet, 3 is a center pole, and 4 is a plate. The magnet 2, center pole 3, plate 4, and yoke 1 constitute a magnetic circuit. Reference numeral 5 denotes a throat, one end of which is connected to a horn 6 whose cross-sectional area is gradually increased, and the other end is fixed to the yoke 1 via a diaphragm packing 7.

A diaphragm 8 consisting of a diaphragm 8a is provided on the front surface of the center pole 3, and an edge portion 8
The outer periphery of b is sandwiched and supported between diaphragm packings 7. A voice coil 9 is provided in the cylindrical portion of the diaphragm 8 and placed in the magnetic gap between the center pole 3 and the plate 4.

An equalizer 10 for eliminating phase interference is provided in front of the diaphragm 8a with a predetermined gap therebetween. Reference numeral 11 is a porous material that has an appropriate acoustic resistance effect and a damping effect against the split vibration of the diaphragm 8a, and does not have much stiffness against the vibration of the diaphragm. Note that this porous material 1
1 is a fibrous material such as sponge, felt, glass wool, or other sound-absorbing material that has air bubbles connected to each other and allows air to pass through. The porous material 11 is provided between the diaphragm 8a and the equalizer 10 and between the edge portion 8b and the throat 5 so that both end surfaces thereof lightly abut.

With the above configuration, when a sound current flows through the voice coil 9, the diaphragm 8a vibrates, but the diaphragm 8a vibrates as a piston in the low frequency range.
As the frequency increases, split vibrations begin. However, this piston vibration and split vibration
Vibration is absorbed by the braking resistance of the porous material 11 provided between the diaphragm 8a and the equalizer 10, and the frequency characteristics are flattened.
However, the resonance of the edge portion 8b itself is absorbed by the damping resistance of the porous material provided between the edge portion 8b and the throat 5, and only a small amount remains. The sound waves caused by the resonance of the edge portion 8b that is present in the porous material 1
The acoustic resistance of 1 causes the energy of the sound wave to be consumed while passing through this material, and controls the propagation of this sound wave toward the diaphragm 8a and the equalizer 10. Both of these effects improve transient characteristics and flatten frequency characteristics.

Due to the increased acoustic resistance of the porous material 11, resonance, which is a factor in deteriorating characteristics compared to conventional speakers, is generated.
It is now possible to provide sufficient damping to FM, and it is possible to improve the lack of damping of resonance FM, which is the biggest cause of deterioration of transient characteristics in conventional speakers.
The transient characteristics and frequency characteristics are improved.

In addition, a part of the energy of the sound waves is consumed by the acoustic resistance of the porous material 11, so the acoustic capacity of the air chamber in front of the diaphragm becomes smaller, which increases the treble reproduction limit frequency and impairs the high-frequency characteristics. Improved. Furthermore, the acoustic resistance of the porous material 11 improves transient characteristics in high frequencies. Moreover, when the high-frequency characteristics are the same as before, the distance between the diaphragm 8 and the equalizer 10 can be made larger than before, so even if there is a large input that causes a large amplitude on the diaphragm 8a, It can be reproduced faithfully.

Although this embodiment shows a horn speaker, the present invention can also be applied to other speakers,
For example, the present invention can be applied to dome-shaped, leaf-shaped, ribbon-shaped speakers, and earphones by using means such as providing an appropriate partition or holder in front of the diaphragm.

Since the present invention is configured as described above, the present invention has excellent transient characteristics compared to conventional speakers, can raise the treble reproduction limit frequency, and has flattened frequency characteristics. It is possible to provide a high-quality horn/speaker.

Note that the configuration of the present invention is not limited to the above-mentioned embodiments, but can be freely modified within the scope of the purpose of the present invention, and the present invention encompasses all of these.

[Brief explanation of drawings]

The drawing is a sectional view showing an embodiment of a horn speaker according to the present invention. 1... Yoke, 2... Magnet, 3... Center pole, 4... Plate, 5... Throat,
6...Horn, 7...Diaphragm packing, 8
... diaphragm, 8a ... diaphragm, 8b ... edge section, 9 ... voice coil, 10 ... equalizer, 11 ... porous material.

Claims (1)

[Claims] 1. A horn speaker characterized in that the entire space between the diaphragm diaphragm and the equalizer and between the edge and throat of the diaphragm is filled with a soft porous material.