WO2022259615A1

WO2022259615A1 - Wearable speaker

Info

Publication number: WO2022259615A1
Application number: PCT/JP2022/005003
Authority: WO
Inventors: 隆志弦本
Original assignee: ソニーグループ株式会社
Priority date: 2021-06-11
Filing date: 2022-02-09
Publication date: 2022-12-15

Abstract

The present invention improves the sound quality of a wearable speaker.　A wearable speaker comprising a pair of speakers attached to the ends of an attachment band, each speaker including a housing, the housing including: a speaker unit attachment surface to which a speaker unit is attached; a wall portion facing the speaker unit at a predetermined angle; and a slope surface extending at an angle from a vicinity of an end portion of the speaker unit attachment surface toward the speaker unit.

Description

wearable speaker

This technology relates to wearable speakers.

In recent years, there have been proposals for devices called neck speakers or neckband speakers, in which speakers are placed around the neck or on the shoulders to listen to voices and music (see Patent Document 1, for example).

WO2018/110160

In this field, it is desired to improve sound quality as much as possible.

One of the purposes of this technology is to provide a wearable speaker with improved sound quality.

For example, this technology
having a pair of speakers attached to opposite ends of the mounting band;
each speaker has a housing,
The housing is
a speaker unit mounting surface on which the speaker unit is mounted;
a wall facing the speaker unit at a predetermined angle;
The wearable speaker has a slope surface that inclines toward the speaker unit from the vicinity of the end of the speaker unit mounting surface.

FIG. 1 is a diagram showing a wearing state of a neck speaker according to one embodiment. FIG. 2 is a diagram referred to when describing a configuration example of a neck speaker according to an embodiment. FIG. 3 is a diagram referred to when describing a configuration example of a neck speaker according to an embodiment. FIG. 4 is a diagram that is referred to when describing a configuration example of a left speaker according to an embodiment. 5A and 5B are diagrams referred to when describing a configuration example of a left speaker according to an embodiment. 6A, 6B, and 6C are diagrams referred to when describing a configuration example of a left speaker according to an embodiment. FIG. 7 is a diagram referred to when describing the details of the slope surface according to one embodiment. FIG. 8 is a diagram referred to when describing the details of the slope surface according to one embodiment. FIG. 9 is a diagram referred to when describing the details of the slope surface according to one embodiment. FIG. 10 is a diagram referred to when describing the electrical configuration of the neck speaker according to one embodiment. 11A and 11B are diagrams referred to when explaining effects obtained by the neck speaker according to the embodiment. FIG. 12A and 12B are diagrams referred to when explaining effects obtained by the neck speaker according to the embodiment. FIG. 13A to 13C are diagrams referred to when explaining the effects obtained by the neck speaker according to one embodiment. 14A and 14B are diagrams referred to when explaining the effects obtained by the neck speaker according to the embodiment. FIG. 15A and 15B are diagrams referred to when explaining the effects obtained by the neck speaker according to the embodiment. FIG. 16A and 16B are diagrams referred to when explaining effects obtained by the neck speaker according to the embodiment. FIG. 17A and 17B are diagrams referred to when explaining effects obtained by the neck speaker according to the embodiment. FIG. 18A and 18B are diagrams referred to when explaining effects obtained by the neck speaker according to the embodiment. FIG.

Hereinafter, embodiments and the like of the present technology will be described with reference to the drawings. The description will be given in the following order.
<Problems to be considered in this technology>
<One embodiment>
<Modification>
The embodiments and the like described below are preferred specific examples of the present technology, and the content of the present technology is not limited to these embodiments and the like.
In addition, in the following description, in order to prevent the illustration from becoming complicated, there are cases in which only part of the configuration is given reference numerals, or in which part of the configuration is illustrated in a simplified manner.

<Problems to be considered in this technology>
First, in order to facilitate understanding of the present technology, issues to be considered in the present technology will be described.

In recent years, as one type of wearable speaker, a device has been proposed in which a speaker is placed around the neck or on the shoulder to listen to voice or music (hereinafter referred to as a neck speaker as appropriate). Such a neck speaker has the advantage of being able to enjoy powerful sound with less energy by simply wearing a small device, compared to the case where a speaker is placed in a room or near a person.

Also, when using the neck speaker, there is no need to play a loud sound to the surroundings, so there is no need to set up a soundproof room. In addition, if wireless devices are used, such as by using radio, it is possible to listen to voice or music with the same sound quality at all times even when moving around freely. In this way, the neck speaker has advantages that are not found in stationary speakers, such as a small amount of energy, no sound leaking to the surroundings, and a uniform sound that can be heard even when moving freely. .

Wearable speakers other than neck speakers include headphones and earphones. Headphones have devices that emit sound waves placed on the left and right ears, and the devices cover the ears. Earphones prevent external sounds from entering by closing the ear canal with a device such as an earpiece, and block ambient sounds with less energy. This allows the user to listen to clear audio.

However, these devices that are worn in contact with the ear or its surroundings place a burden on the human body on the ear or the vicinity of the ear, and especially with headphones, the user can feel pain and fatigue when wearing them for a long time. Although various devices have been devised at great cost to reduce this load, a fundamental solution is difficult. In this regard, the neck speaker has the advantage of being able to reduce the burden, discomfort, and fatigue felt by the user because it can be placed on the shoulder and the weight can be relatively small.

Earphones have a smaller load than headphones. However, in terms of sound quality, they are generally inferior to headphones. When listening to voices or music while wearing headphones or earphones, it is difficult to hear surrounding sounds, which hinders the use of such devices in daily life at home. For example, when someone talks to us, when a doorbell or alarm sounds, or when an abnormal sound occurs in our daily life, we are unaware of it and cannot respond appropriately. This also raises security issues in daily life.

In this regard, since the area around the ears is not blocked with the neck speaker, the surrounding sounds can be heard at the same time, so the above-mentioned problems are less likely to occur. In terms of sound quality, both headphones and earphones produce sounds with a strong sense of blockage, but the neck speaker has less of a feeling of blockage and sounds more natural and open. In addition, in most cases, headphones and earphones are not subjected to predetermined audio processing, and sound images are localized in the head (intracerebral localization), causing a sense of discomfort. In the case of a neck speaker, by devising the arrangement of the speaker unit and the structure of the diffuser, it is possible to easily reduce the localization of the sound image in the head and to create a sense of spaciousness of the sound.

Although the neck speaker has the above advantages, it has the problem that it is difficult to stabilize the sound quality. This is because when the neck speaker is placed on the shoulder and sound is reproduced near the ear, the sound quality changes due to a slight displacement of the position of the neck speaker. The auricle of the ear has a complex shape mainly to collect surrounding sounds and increase sensitivity and to know the direction of sound. However, as for the sound emitted from above the shoulder directly below the auricle, the sound quality changes even with a slight deviation of the reproduction position, partly because it is the boundary between the front and back of the auricle. As a result, when the neck is moved or when the mounting position of the speaker unit is displaced due to a difference in body shape, the sound quality changes. If the speaker is placed in front of the auricle on the line from the shoulder to the chest instead of directly under the auricle, the center axis of the sound from the speaker will be shifted from the position of the ear, resulting in deterioration of the frequency characteristics. Even if the direction of the speaker is directed toward the ear at the position of the speaker, the center axis of the sound of the speaker is shifted due to the change in the position of the ear or the difference in body shape, and the change in sound quality cannot be completely eliminated. In addition to improving the sound quality, this technology also improves the diffusion function to minimize changes in sound quality caused by changes in body shape or when the neck is moved. Based on the above, the present technology will be described in detail using one embodiment.

[Example of neck speaker appearance]
FIG. 1 is a perspective view showing the appearance of a neck speaker 100 according to one embodiment. The neck speaker 100 includes a neck hanging portion 10 which is an example of a mounting band, a left speaker 20 connected to one end side of the neck hanging portion 10, and a right speaker 30 connected to the other end side of the neck hanging portion 10. have. The neck speaker 100 constitutes a two-channel audio reproduction system as a whole.

For example, as shown in FIG. 1, the neck speaker 100 is hung on the back of the neck of the listener L, the left speaker 20 is near the left side of the listener L, and the right speaker 30 is on the right shoulder of the listener L. Used while in contact (placed) nearby. At this time, the side of the left speaker 20 opposite to where it is connected to the neck portion 10 (hereinafter referred to as the tip side or the front side) is slightly inclined toward the front of the listener L. As shown in FIG. Similarly, the tip side of the right speaker 30 is slightly inclined toward the front of the listener L. As shown in FIG. Sound is reproduced from the neck speaker 100 in the wearing state as shown in FIG. The sound may be anything that can be heard by human ears, such as a human voice or music. In the following description, directions such as up, down, front, back, left, right, inside, outside, horizontal, and vertical directions are defined with reference to the listener L when the neck speaker 100 is worn.

[Configuration example of neck speaker]
(Overall configuration example)
Next, a configuration example of the neck speaker 100 will be specifically described with reference to FIGS. 2 and 3 in addition to FIG. FIG. 2 is a perspective view of neck speaker 100 according to one embodiment. FIG. 3 is a top view of the neck speaker 100 according to one embodiment.

As shown in FIGS. 2 and 3, the neck hanging part 10 has, for example, a slider 11, and by sliding the slider 11, the length between the left and right speakers can be adjusted.

As shown in FIGS. 2 and 3, the left speaker 20 has a housing 21. As shown in FIG. The housing 21 generally has a box shape. The housing 21 is made of plastic resin, for example.

The housing 21 has a speaker unit mounting surface 22, a wall portion 23, and a slope surface 24. The speaker unit mounting surface 22 is slightly outwardly inclined, and the speaker unit SPA (speaker cone) is mounted on the speaker unit mounting surface 22 . A full-range dynamic speaker, for example, can be applied as the speaker unit SPA. The wall portion 23 has, for example, a thin plate-like and rectangular shape, and faces the speaker unit mounting surface 22 at a predetermined angle. The predetermined angle is, for example, approximately 45 degrees (45 degrees or 45±5 degrees). A passive radiator PRA (not visible in FIGS. 2 and 3) is attached to the surface 26 facing the inside of the housing 21 . The passive radiator PRA is made of vulcanized or non-vulcanized rubber such as isobutylene-isoprene rubber (IIR) or acrylonitrile-butadiene rubber (NBR). embedded with a metal plate.

The right speaker 30 has the same shape as the left speaker 20. As shown in FIGS. 2 and 3, the right speaker 30 has a housing 31. As shown in FIG. The housing 31 is made of plastic resin, for example.

The housing 31 generally has a box shape. The housing 31 has a speaker unit mounting surface 32 , a wall portion 33 and a slope surface 34 . The speaker unit mounting surface 32 is slightly outwardly inclined, and the speaker unit SPB is mounted on the speaker unit mounting surface 32 . For example, a full-range dynamic speaker can be applied as the speaker unit SPB. The wall portion 33 has a thin plate-like and rectangular shape, and faces the speaker unit mounting surface 32 at a predetermined angle. The predetermined angle is, for example, approximately 45 degrees (45 degrees or 45±5 degrees). A passive radiator PRB is attached to the surface 36 facing the inside of the housing 31 . The passive radiator PRB is made of vulcanized or non-vulcanized rubber such as isobutylene-isoprene rubber (IIR) or acrylonitrile-butadiene rubber (NBR). embedded with a metal plate.

(Speaker configuration example)
A configuration example of the left and right speakers of the neck speaker 100 will be described in detail with reference to FIGS. 4, 5, and 6. FIG. Although the left speaker 20 will be described below as an example, the matters described below can also be applied to the right speaker 30 .

4 is a perspective view of the left speaker 20 (including a passive radiator) according to one embodiment, FIG. 5A is a perspective view of the left speaker 20 with the slope surface and the passive radiator removed, and FIG. 5B is the left speaker with the passive radiator removed. 20 is a perspective view of FIG. 6A to 6C are views of the left speaker 20 viewed from above, a view of the left speaker 20 viewed from the side, and a view of the left speaker 20 viewed from the back (rear end surface of the housing 21). be. 4, 5 and 6, the illustration of the left speaker 20 is simplified as compared with FIG. 2 and the like for easy understanding.

As shown in FIGS. 4 and 6C, the housing 21 of the left speaker 20 has a housing portion 21A in the shape of a triangular prism whose cross section is similar to a substantially right-angled isosceles triangle. A bottom surface 221A, which is one of the side surfaces of the housing part 21A, contacts the listener L near the shoulder. In order to reduce the load on the listener L, a cushion member or the like may be provided on the bottom surface 221A.

In the present embodiment, the inclined side surface of the housing portion 21A serves as the speaker unit mounting surface 22. A speaker unit SPA is attached to the speaker unit attachment surface 22 . As shown in FIG. 5A, the wall portion 23 is erected at approximately 45 degrees with respect to the speaker unit mounting surface 22 .

As shown in FIGS. 4, 5B, and 6C, the housing 21 has a housing portion 21B provided between the speaker unit mounting surface 22 of the housing portion 21A and the wall portion 23. As shown in FIGS. The peripheral surface of the housing portion 21B, specifically, the peripheral surface positioned between the speaker unit mounting surface 22 and the wall portion 23 serves as a slope surface 24. As shown in FIG. As shown in FIGS. 4, 5B, 6A, and 6B, in the present embodiment, the slope surface 24 extends from near one end (for example, near the rear end) of the speaker unit mounting surface 22 to the speaker unit. A slope surface 24A, which is an example of a first slope surface that inclines toward the SPA, and a second slope surface that inclines from near the other end (for example, near the front end) of the speaker unit mounting surface 22 toward the speaker unit SPA. and a slope surface 24B, which is an example of the slope surface of . In this embodiment, the magnitude of the gradient of the slope surface 24A and the magnitude of the gradient of the slope surface 24B are different.

The housing portion 21A of the housing 21 is hollow, and the hollow space functions as an enclosure for the speaker unit SPA. Further, in the present embodiment, the housing portion 21B is also hollow, and the internal space of the housing portion 21A communicates with the internal space of the housing portion 21B. This makes it possible to increase the capacity of the enclosure of the speaker unit SPA.

The speaker unit SPA is provided on the opposite side of the housing 21 from the side on which the neck hook 10 is attached. For example, the speaker unit SPA is provided on the front side with respect to the central position in the front-rear direction of the housing 21 (specifically, the speaker unit mounting surface 22). As a result, the listener L can perceive that the sound is being reproduced from a slightly forward direction. For example, when listening to the sound of a television device using the neck speaker 100, the sound can be reproduced from the front side with a more natural feeling. Depending on the application of the neck speaker 100 (for example, reproducing a recorded conversation), it is not always necessary to reproduce sound from the front side. 22).

As shown in FIG. 4, a passive radiator PRA is provided on a surface 26 facing the inside (listener L side) of the side surfaces of the housing portion 21A. By providing the passive radiator PRA only on the inside, it is possible to arrange operation buttons or print a logo or the like in the outside space (for example, the space facing the outside of the wall portion 23). In addition, as shown in FIG. 4, a passive radiator PRA' may be provided on the outside, specifically, on the surface of the wall 23 facing the outside. As a result, when the two passive radiators vibrate, the two passive radiators move in opposite directions, so that the vibration of the center of gravity of the entire neck speaker 100 can be reduced, resulting in stable mounting.

(Regarding the slope surface)
Next, details of the slope surface 24 according to the present embodiment will be described with reference to FIGS. 7 to 9. FIG. FIG. 7 shows the speaker unit mounting surface 22 and the substantially circular speaker unit SPA. The portion of the illustrated speaker unit SPA may be a hole to which the speaker unit SPA is attached.

A line in contact with the upper vertex of the speaker unit SPA in FIG. 7 and parallel to the longitudinal direction of the speaker unit mounting surface 22 is defined as an upper line LA. A line in contact with the lower vertex of the speaker unit SPA in FIG. 7 and parallel to the longitudinal direction of the speaker unit mounting surface 22 is defined as a lower line LB. A line connecting the upper vertex and the lower vertex of the speaker unit SPA (the center line of the speaker unit SPA extending vertically toward FIG. 7) is defined as a line LC.

In the present embodiment, as shown in FIG. 7, the outer edge 244A of the slope surface 24A (the outer edge in contact with the speaker unit mounting surface 22) and the outer edge 244B of the slope surface 24B are connected via a curve 244C.

A setting example of the

outer edges

244A and 244B will be described. The ellipse AA is set by increasing the diameter of the outer edge of the substantially circular shape of the speaker unit SPA. The major axis of the ellipse AA on the left and right sides of the center may be the same or may be different. In this embodiment, the ellipse AA is defined by multiplying the left radius by 1.2 times and the right radius by 1.6 times. A portion of ellipse AA forms curve 244C.

Next, set ellipse BB and ellipse CC. Ellipses BB and CC are ellipses whose major or minor axis lies on the lower line LB and are defined to circumscribe ellipse AA. As the ellipses BB and CC, ellipses and hyperbolas having the lower line LB as an axis can also be considered.

The ellipse BB is centered on the lower line LB, and after determining a passing point that intersects the rear end of the housing 21, the ellipse BB circumscribes the ellipse AA, in other words, is smoothly connected to the curve 244C. Draw like The ellipse CC is centered on the lower line LB, determines a passing point that intersects the front end of the housing 21, and then circumscribes the ellipse AA, in other words, is smoothly connected to the curve 244C. Draw like The curvature of the

outer edges

244A and 244B changes the sound quality, but by changing the position of the center of each ellipse in the horizontal direction and changing the passing point, the

outer edges

244A and 244B that can obtain the desired sound quality are defined. can.

Next, as shown in FIG. 8, for example, for any point on the outer edge 244A, define a line 41 that forms an angle between 10 and 15 degrees with respect to the horizontal plane (eg, the bottom surface 221A). Line 41 is a line that slopes upward from the outside to the inside in a range of 10 to 15 degrees. Such line 41 contacts the wall portion 23 . A similar line 41 and the point where the line 41 contacts the wall 23 are determined for several points of the outer edge 244A. A line connecting the points where the line contacts the wall portion 23 forms an outer edge 245A opposite to the outer edge 244A of the slope surface 24A. An outer edge 245B on the side opposite to the outer edge 244B of the slope surface 24 is obtained by defining the line 42 and performing the same processing on the outer edge 244B of the slope surface 24B. The reason why the line 41 forms an angle between 10 degrees and 15 degrees with respect to the horizontal plane is that the vertical direction of the slope surface 24 obtained by this processing becomes the position near the ear, and the neck speaker 100 reproduces. This is because sound can be effectively propagated in the direction of the ear.

The slope surface 24A obtained by such a method can also be said to be a set of lines 41 parallel to each other, as shown in FIG. The lines 41 parallel to each other gradually become shorter in length from the rear side of the slope surface 24A, and the length becomes substantially zero in the vicinity PP of the speaker unit SPA. Approximately 0 means 0 or a length that can be equated with 0 (for example, several millimeters). Also, the slope surface 24B can be said to be a set of lines 42 parallel to each other, as shown in FIG. The lines 42 parallel to each other gradually decrease in length from the front side of the slope surface 24B, and the length becomes substantially zero in the vicinity PP of the speaker unit SPA. The

lines

41 and 42 do not intersect, that is, the slope surface 24 is prevented from twisting.

The setting example of the slope surface 24 described above is an example, and the slope surface 24 may be defined by other methods. However, when optimizing the shape of the slope surface 24, it is desirable that the surface that reflects sound is convex. This is because if the sound reflecting surface is concave, the frequency characteristics may be disturbed. In the above example, the portion of the ellipse AA (the portion of the curve 244C) is concave. There is no big effect even if it is Preferably, there is no portion of curve 244C of ellipse AA and outer edge 244A and outer edge 244B are directly connected.

[Electrical Configuration of Neck Speaker]
Next, the electrical configuration of neck speaker 100 will be described with reference to the block diagram of FIG. In FIG. 10, solid lines indicate L (Left) channel audio signals, thick dotted lines indicate R (Right) channel audio signals, and thin dotted lines indicate control signals and commands.

The neck speaker 100 includes a processor 51, an antenna 52, an RF (Ratio Frequency) receiver 53, an input terminal 54, an input switcher 55, a digital signal processor 56, an amplifier (AMP) 57, and an amplifier 58. and a power source 59 .

The processor 51 is composed of, for example, a CPU (Central Processing Unit). In addition, the processor 51 has a ROM (Read Only Memory) in which programs executed by the processor 51 are stored, a RAM (Random Access Memory) used as a work area, and the like (illustration of these memories is omitted). ing.). Processor 51 centrally controls each part of neck speaker 100 . For example, a user operation is performed to instruct an operation input unit (not shown) provided in the neck speaker 100 to play or stop audio. An operation signal generated according to a user's operation is input to the processor 51 . The processor 51 analyzes the content of the operation signal and executes control according to the operation signal.

The antenna 52 receives two-channel audio signals transmitted from an external electronic device based on a predetermined wireless communication standard. Examples of external electronic devices include personal computers, smart phones, portable audio playback devices, and the like. Further, the predetermined wireless communication standard includes wireless LAN (Local Area Network), Bluetooth (registered trademark), WiFi (registered trademark), infrared communication, and the like.

An audio signal received by the antenna 52 is supplied to the RF receiver 53 . The RF receiver 53 performs demodulation processing, error correction processing, and the like on the input audio signal. A signal processed by the RF receiving unit 53 is supplied to the input switching unit 55 .

The input terminal 54 is a terminal for connecting the neck speaker 100 and an external electronic device by wire. An audio signal may be taken into the neck speaker 100 via the input terminal 54 .

The input switching unit 55 is a switch for switching between audio signal input from the RF receiving unit 53 and audio signal input from the input terminal 54 . The input switching unit 55 switches inputs under the control of the processor 51, for example. The audio signal selected by the input switching section 55 is supplied to the digital signal processing section 56 .

The digital signal processing unit 56 is configured by, for example, a DSP (Digital Signal Processor). The digital signal processing section 56 has, for example, a low frequency cut filter 56A, an equalizer 56B, and a volume adjustment section 56C. The low-frequency cut filter 56A is a filter that cuts low-frequency components included in the audio signal. The equalizer 56B corrects the frequency characteristics of the audio signal, and is composed of, for example, a secondary IIR (Infinite Impulse Response) filter. The volume adjuster 56C adjusts the volume of sounds reproduced from the speaker units SPA and SPB by adjusting the level of the audio signal.

Of the audio signals that have undergone signal processing by the digital signal processing unit 56 , the audio signal of the left channel is supplied to the amplifier 57 . An audio signal amplified with a predetermined amplification factor by the amplifier 57 is reproduced from the speaker unit SPA. Of the audio signals subjected to signal processing by the digital signal processing unit 56 , the right channel audio signal is supplied to the amplifier 58 . An audio signal amplified with a predetermined amplification factor by the amplifier 58 is reproduced from the speaker unit SPB.

The power supply 59 includes a secondary battery such as a lithium ion battery, a circuit for charging and discharging, and the like. The power supply 59 is not limited to a secondary battery, and may be a primary battery, an electric double layer capacitor, a lithium ion capacitor, or the like.

The configuration described above is housed inside the housing 21 (the housing 31 or the neck hanging portion 10 may be used).

[Effect obtained by the present embodiment]
(Effect obtained by providing a wall portion)
Next, an example of the effects obtained by this embodiment will be described. First, the effect obtained by providing the wall portion 23 and the wall portion 33 will be described.

The wall portion 23 (the same applies to the wall portion 33) has a height such that the speaker unit SPA cannot be seen when the neck speaker 100 is viewed from the horizontal direction, and the length in the front-rear direction is approximately the same as the length in the front-rear direction of the housing 21. I have to. By providing the wall portion 23, it is possible to increase the reflection of sound toward the ears. The reason why the height of the wall portion 23 is set so that the speaker unit SPA cannot be seen is that the reflection of sound can be increased, the usability is improved, and the design is facilitated.

We measured how the sound pressure changes when the wall portion 23 is provided and when it is not provided. Measurements were performed as shown in FIG. A speaker unit of φ25 mm was used as the speaker unit SPA. A measurement microphone MC was placed at a position corresponding to the ear. Specifically, as shown in FIG. 11, a side 61 is a side where the speaker unit mounting surface 22 and the wall portion 23 intersect. A line parallel to the side 61 intersects with the extending direction of the short side on the rear side of the wall portion 23, and the measurement microphone MC is arranged assuming that the position of the ear is the position where the distance D1 to the speaker unit SPA is 20 cm. An audio signal containing a wide band was reproduced from the speaker unit SPA. Further, the wall portion 23 is provided so as to form an angle of 45 degrees with respect to the speaker unit mounting surface 22, as in the case of the one embodiment.

An audio signal was picked up by the measurement microphone MC, and changes in sound pressure were measured with and without the wall 23 provided. The results (frequency characteristics) are shown in FIG. The horizontal axis of the graph in FIG. 12 indicates frequency, and the vertical axis indicates sound pressure. Further, the line L10 in the graph of FIG. 12 indicates the frequency characteristics when the wall portion 23 is provided, and the line L10 indicates the frequency characteristics when the wall portion 23 is not provided. When the wall portion 23 is not provided, the measurement microphone MC is located at a position greatly deviated from the front of the speaker unit SPA. Therefore, the level of high frequencies (4 kHz or higher in this example) is remarkably lowered. On the other hand, when the wall portion 23 is provided, sound can be reflected by the wall portion 23, so that the reduction in sound pressure in high frequencies can be suppressed.

(About the angle between the speaker unit mounting surface and the wall)
Next, the effect obtained by setting the angle .theta. between the speaker unit mounting surface and the wall to approximately 45 degrees will be described. FIG. 13A shows an example where the angle θ is greater than 45 degrees (θ=90 in this example). FIG. 13B shows an example where the angle θ is approximately 45 degrees (θ=45 in this example). FIG. 13C shows an example where the angle θ is smaller than 45 degrees (25 degrees in this example). The position of the measurement microphone MC is the same as the position shown in FIG.

We measured the change in sound pressure when the same audio signal was reproduced by changing the angle θ. The results (frequency characteristics) are shown in FIG. The horizontal axis of the graph in FIG. 14 indicates frequency, and the vertical axis indicates sound pressure. Line L21 in the graph of FIG. 14 indicates the frequency characteristics when θ=90, L22 indicates the frequency characteristics when θ=45, and L23 indicates the frequency characteristics when θ=25.

As shown by line L21, when θ=90, the drop in sound pressure in the high range becomes significant. It is considered that this is because when θ=90, the wall portion 23 is almost absent. When θ=45, the sound pressure drop in the high range is suppressed, and the frequency fluctuations (peaks and valleys) are small and flat. When .theta.=25, as shown by line L23, the frequency characteristic becomes more violent than that of line L22, and the drop in sound pressure in the high range of 5 kHz or higher becomes large. Therefore, it is preferable that θ is approximately 45 degrees.

When θ is approximately 45 degrees, it is superior in terms of design. If θ is 90 degrees, the width W of the neck speaker 100 shown in FIG. 13A becomes large, and handling of the neck speaker 100 may become inconvenient. On the other hand, even if .theta. is smaller than 45 degrees, the width W cannot be extremely reduced because the size of the housing portion 21A functioning as an enclosure for the speaker unit SPA must be at least a certain size. From this point of view as well, it can be said that θ is preferably approximately 45 degrees.

(Effect obtained by providing a slope surface)
Next, the effect obtained by providing the slope surface 24 will be described. In the configuration of the neck speaker 100 provided with the wall portion 23, the same audio signal was reproduced with and without the slope surface 24, and changes in the sound pressure were measured. The position of the measurement microphone MC was the same as the position shown in FIG.

The results (frequency characteristics) are shown in FIG. The horizontal axis of the graph in FIG. 15 indicates frequency, and the vertical axis indicates sound pressure. Line L31 in the graph of FIG. 15 indicates frequency characteristics when the slope surface 24 is provided, and line L32 indicates frequency characteristics when the slope surface 24 is not provided. As shown by line L31, when slope surface 24 is provided, sound can be effectively reflected in the direction of the ear. 10 kHz or higher) can be suppressed. Moreover, it is also possible to adjust the frequency band, specifically, the range from 1 kHz to 5 kHz, in which the sound pressure could not be adjusted with the wall portion 23 . That is, by providing the slope surface 24, the overall average sound pressure can be increased, and the characteristics in the range of 1 kHz to 5 kHz, for example, can be made flatter.

Next, it was measured how the sound pressure changes depending on the presence or absence of the slope surface 24 when the position of the ear with respect to the left speaker 20 changes according to the difference in body shape. As shown in FIG. 16, the measurement was performed by arranging the measurement microphone MC at three different positions. Specifically, a line L50 passing through the center of the speaker unit SPA and extending in the longitudinal direction of the housing 21 is defined, and the measurement microphones are placed at positions forming 20 degrees, 30 degrees, and 45 degrees with respect to the line L50, respectively. The MC was placed and measured.

The frequency characteristics in FIG. 17 show the measurement results when the slope surface 24 is provided. Line L41 in FIG. 17 indicates the measurement result when the measurement microphone MC is placed at the position of 20 degrees, line L42 indicates the measurement result when the measurement microphone MC is placed at the position of 30 degrees, and line L43 indicates the measurement result when the measurement microphone MC is placed at the position of 30 degrees. The measurement results when the measurement microphone MC is placed at a position of 45 degrees are shown.

The frequency characteristics in FIG. 18 show measurement results when the slope surface 24 is not provided. Line L51 in FIG. 18 indicates the measurement results when the measurement microphone MC is placed at a position of 20 degrees, line L52 indicates the measurement results when the measurement microphone MC is placed at a position of 30 degrees, and line L53 indicates the measurement results. 10 shows the measurement results when the microphone MC for the sound is placed at a position of 45 degrees.

When comparing FIGS. 17 and 18, in the vicinity of frequencies of 6 kHz or higher (locations circled with dotted lines), when the slope surface 24 is provided, the change in the frequency characteristics due to the change in the position of the measurement microphone MC is small. . On the other hand, when the slope surface 24 is not provided, the change in the frequency characteristic due to the change in the position of the measurement microphone MC becomes large. That is, by providing the slope surface 24, even if the position of the ear with respect to the left speaker 20 changes according to the difference in body type, etc., it is possible to suppress the change in sound quality caused by the change.

From the above, it was found that the configuration in which the wall portion 23 is provided and the slope surface 24 is provided is preferable in terms of improving the sound quality.

<Modification>
An embodiment of the present technology has been specifically described above, but the present technology is not limited to the above-described embodiment, and various modifications are possible based on the technical idea of the present technology. A plurality of modified examples will be described below.

The shapes of the left speaker and the right speaker are examples, and the shapes can be changed as appropriate without departing from the gist of the present technology. For example, in the embodiment, the speaker unit and the speaker unit mounting surface both on the left and right face outward, but they may face inward. When facing inward, the wall is also arranged inward. Moreover, the slope surface 24 described in one embodiment may be configured by either one of the slope surface 24A and the slope surface 24B.

The shape of the speaker mounting surface and wall is not limited to a rectangular shape, and may be other shapes. Also, the height of the wall may not be constant. For example, the amount of sound reflection may be increased by partially increasing the height of the wall at the location facing the speaker unit. Also, the height of the wall may be lowered at a location away from the speaker unit. When using a loudspeaker unit with a large diameter, the height of the wall becomes high, and there is a risk that the rear wall, in particular, will come into contact with the human body such as the chin. By reducing the height of the rear side of the wall, it is possible to prevent contact between the wall and the human body.

In the embodiment described above, a neck speaker was used as an example of a wearable speaker, but the present invention is not limited to this. The wearable speaker may be, for example, an open speaker device that reproduces sound near the ear without sealing the auricle, and is, for example, a speaker device applied to a head-mounted display worn on the head. may That is, the attachment band is not limited to the one worn around the neck, and may be attached to the head or arm.

The configurations, methods, processes, shapes, materials, numerical values, and the like given in the above-described embodiments are merely examples, and if necessary, different configurations, methods, processes, shapes, materials, numerical values, and the like may be used. good. The embodiments and modifications described above can be combined as appropriate.

Note that the effects described here are not necessarily limited, and may be any effect described in the present technology. Moreover, the contents of the present technology are not to be construed as being limited by the illustrated effects.

The present technology can also adopt the following configuration.
(1)
having a pair of speakers attached to opposite ends of the mounting band;
each said speaker has a housing,
The housing is
a speaker unit mounting surface on which the speaker unit is mounted;
a wall facing the speaker unit at a predetermined angle;
A wearable speaker comprising: a slope surface that slopes from near an end of the speaker unit mounting surface toward the speaker unit.
(2)
The wearable speaker according to (1), wherein the predetermined angle is approximately 45 degrees.
(3)
The speaker unit mounting surface has a substantially rectangular shape,
The slope surface includes a first slope surface that inclines from near one end of the speaker unit mounting surface toward the speaker unit, and a first slope surface that tilts from near the other end of the speaker unit mounting surface toward the speaker unit. The wearable speaker according to (1) or (2), further comprising an inclined second slope surface.
(4)
(3) The wearable speaker according to (3), wherein the magnitude of the gradient of the first slope surface and the magnitude of the gradient of the second slope surface are different.
(5)
The slope surface is formed by a set of lines parallel to each other, and the length of the lines gradually becomes shorter from the end of the speaker unit mounting surface toward the speaker unit, and extends near the outer edge of the speaker unit. The wearable speaker according to any one of (1) to (4).
(6)
The wearable speaker according to any one of (1) to (5), wherein the slope surface is upwardly inclined within a range of 10 degrees to 15 degrees from the outside toward the inside.
(7)
The wearable speaker according to any one of (1) to (6), wherein the speaker unit is provided on the side of the housing opposite to the side on which the mounting band is attached.
(8)
The wearable speaker according to any one of (1) to (7), further comprising a passive radiator.

20 Left speaker 21 Housing 22 Speaker unit mounting surface 23

Wall portions

24, 24A, 24B Slope surface 30 Right speaker 31 Housing 32 Speaker unit mounting surface 33 Wall portions 34, 34A, 34B Slope surface 100 Neck speakers SPA, SPB Speaker units PRA, PRB Passive radiator

Claims

having a pair of speakers attached to opposite ends of the mounting band;
each said speaker has a housing,
The housing is
a speaker unit mounting surface on which the speaker unit is mounted;
a wall facing the speaker unit at a predetermined angle;
A wearable speaker comprising: a slope surface that slopes from near an end of the speaker unit mounting surface toward the speaker unit.
The wearable speaker according to claim 1, wherein the predetermined angle is approximately 45 degrees.
The speaker unit mounting surface has a substantially rectangular shape,
The slope surface includes a first slope surface that inclines from near one end of the speaker unit mounting surface toward the speaker unit, and a first slope surface that tilts from near the other end of the speaker unit mounting surface toward the speaker unit. and a second sloped surface that slopes.
The wearable speaker according to claim 3, wherein the magnitude of the gradient of the first slope surface and the magnitude of the gradient of the second slope surface are different.
The slope surface is formed by a set of lines parallel to each other, and the length of the lines gradually becomes shorter from the end of the speaker unit mounting surface toward the speaker unit, and extends near the outer edge of the speaker unit. 2. The wearable speaker according to claim 1, wherein .
The wearable speaker according to claim 1, wherein the slope surface slopes upward from the outside to the inside in a range of 10 degrees to 15 degrees.
The wearable speaker according to claim 1, wherein the speaker unit is provided on the opposite side of the housing from the side on which the mounting band is attached.
The wearable speaker of Claim 1, further comprising a passive radiator.