TW202435198A - Device and method of equalizing low frequency roll off for wearable sound device - Google Patents

Abstract

A wearable sound device includes a venting module, configured to form at least one vent to connect a volume within the wearable sound device and ambient, and a sound producing device, configured to produce sound according to an equalized input signal. The venting module, including at least one venting device, operates among a plurality of statuses corresponding to a plurality of degrees of opening. A controller generates the equalized input signal according to a degree of opening among the plurality of degrees of opening, in order to counteract a roll off caused by the at least one vent.

Description

Device and method for equalizing low frequency roll-off of wearable audio device

The present invention relates to a wearable sound device, a controller and an equalization method, and in particular to a wearable sound device, a controller and an equalization method that can enhance user experience.

The closing effect is the effect of the sealed volume of the ear canal on the sound pressure felt by the listener. For example, the closing effect occurs when the listener wears a wearable sound device (in the ear canal) to engage in certain sports (such as jogging) to produce bone-conducted sound. However, releasing the pressure inside the closed chamber may affect the frequency response and face severe low-frequency roll-off, especially affecting the user experience of the low-frequency part of the music. Therefore, there is still room for further improvement in sound quality optimization.

Therefore, the present invention mainly provides a wearable sound device, a controller and an equalization method to improve the existing technology.

An embodiment of the present invention discloses a wearable sound device, comprising a port module, including at least one port device, used to form at least one port to connect the volume of the wearable sound device with the environment; and a sound generating device, used to generate sound according to an equalized input signal; wherein the port module operates between a plurality of states corresponding to a plurality of opening degrees; wherein a controller generates the equalized input signal according to one of the plurality of opening degrees to offset the roll-off caused by the at least one port.

An embodiment of the present invention discloses a device, including a controller, which is used to generate an equalized input signal according to an opening degree of a port module among a plurality of opening degrees; wherein the port module is used to form at least one port and has the plurality of opening degrees; wherein the controller that generates the equalized input signal is used to offset the roll-off caused by the at least one port.

An embodiment of the present invention discloses an equalization method for generating an equalized input signal for a sound generating device, comprising obtaining a state of a port module among a plurality of states, wherein the port module forming at least one port operates between the plurality of states corresponding to a plurality of opening degrees; and generating the equalized input signal according to the state.

An embodiment of the present invention discloses a wearable sound device, comprising an acoustic transducer for forming at least one opening to connect the volume of the wearable sound device with the environment, and for generating sound according to an equalized input signal; wherein the acoustic transducer operates between a plurality of states corresponding to a plurality of opening degrees; wherein a controller generates the equalized input signal according to one of the plurality of opening degrees to offset the roll-off caused by at least one opening.

FIG. 1 is a schematic diagram of an audio system 10 according to an embodiment of the present invention. The audio system 10 may include port devices 10DV1, 10DV2, a sound generating device 10SPD, driver circuits 10drvC, 10drvC1, 10drvC2, and a controller 10CTR. The port devices 10DV1, 10DV2 and the sound generating device 10SPD may be disposed in a wearable audio device (e.g., an in-ear audio device, an earbud, or a hearing aid). The controller 10CTR may include an equalizer 10EQ, wherein the equalizer 10EQ may be a portion of the controller 10CTR that performs the equalization operation disclosed in the present application. The port devices 10DV1 and 10DV2 together can be regarded as or constitute a port module 10DV.

The port device 10DV1/10DV2 can be operated in an open mode (e.g., FIG. 5(a)) to form a port (e.g., 513vnt in FIG. 5), in a close mode (e.g., FIG. 5(b)) to close or seal the port, or in a comfort mode (e.g., FIG. 5(c)) to slightly open the port. However, the port device 10DV1/10DV2 may affect the sound transmission channel, so the port module 10DV in different states will result in different frequency responses (e.g., low frequency roll off (LFRO)).

For example, FIG. 2 is a diagrammatic representation of the frequency response corresponding to a single venting device configuration without equalization or before equalization according to an embodiment of the present invention. In FIG. 2, each earbud earphone is provided with a single venting device (e.g., 10DV1) and accommodates a single MEMS speaker (1-way). As shown in FIG. 2, the frequency response corresponding to the comfort mode/state (i.e., the dashed line) rolls off slightly below 100 Hz, while the frequency response corresponding to the open mode/state (i.e., the thick solid line) rolls off more significantly/significantly at/towards low frequencies. FIG. 3 is a diagrammatic representation of the frequency response corresponding to a dual venting device configuration without equalization or before equalization according to an embodiment of the present invention. In FIG. 3 , each earbud earphone is equipped with a dual-port device (e.g., 10DV1 and 10DV2) and includes a dynamic driver (DD) and a MEMS speaker (two-way). As shown in FIG. 3 , when both port devices are in a both-open state with their ports open (i.e., thick solid line), the low-frequency roll-off is very severe. However, when both port devices are in a both-close state with their ports closed (i.e., thin solid line), the frequency response curve remains substantially flat at low frequencies. In other words, a condition that allows more sound/air to be exhausted from one side to the other may cause the low-frequency sound produced by the sound generating device 10SPD to be weaker (when measured in a closed or semi-closed cavity (such as the ear canal or ear canal simulator/coupler (such as 711)) than other conditions.

In order to compensate for the (low frequency) roll-off of the port module 10DV in different states, the equalizer 10EQ can use different equalization curves to generate an equalized input signal. The equalizer 10EQ can obtain/access multiple equalization curves EQCV ₁ to EQCV _M and select a specific equalization curve (e.g. EQCV ₁ ) corresponding to the state of the port module 10DV (e.g. double open state). The equalizer 10EQ is selected (or the equalized input signal is generated) to compensate/cancel the roll-off effect caused by the venting (and specifically related to the state of the venting module 10DV) so that the frequency response corresponding to or perceived by the sound under various venting module opening statuses (such as SS2 in Figure 8) remains consistent (i.e. more or less the same).

Specifically, using the equalization of the present application (which generates sound based on the equalized input signal generated by the controller), the first frequency (magnitude) response of the sound perceived in the first opening state corresponding to the minimum opening degree (degree of opening) is substantially the same as the second frequency (magnitude) response of the sound perceived in the second opening state corresponding to the maximum opening degree. That is, the difference between the first amplitude (or sound pressure level (SPL)) of the sound perceived in the first opening state at a specific frequency and the second amplitude (or sound pressure level) of the sound perceived in the second opening state at the specific frequency is less than a certain/specific threshold. Depending on how good the user experience the supplier wants to provide, the threshold can be ±1dB, ±3dB or ±5dB. The perceived sound and/or first/second (amplitude) frequency responses can be obtained via acoustic measurement equipment and/or audio analysis equipment.

For example, FIG. 4 is a schematic diagram of equalization curves 4EQCV ₁ and 4EQCV _M of an embodiment of the present invention. Equalization curve EQCV ₁ or EQCV _M can be implemented by equalization curve 4EQCV ₁ or 4EQCV _M. In FIG. 4, the attenuation of equalization curve 4EQCV ₁ or 4EQCV _M in the frequency range of 100 Hz to 1000 Hz is generally greater than the attenuation of the frequency range below 100 Hz, because equalization curves 4EQCV ₁ and 4EQCV _M are used to compensate for the deviation of the frequency response (at low frequencies). However, the attenuation of equalization curve 4EQCV ₁ below 100 Hz is significantly smaller than the attenuation of equalization curve 4EQCV _M below 100 Hz, so that equalization curve 4EQCV ₁ is suitable for a state where the low-frequency roll-off is more severe. For example, for the double open state, the equalization curve 4EQCV ₁ can be selected, and for the double closed state, the equalization curve 4EQCV _M can be selected.

The equalizer 10EQ can determine the state of the port module 10DV, thereby selecting the equalization curve. Specifically, the controller 10CTR can indicate to the driver circuits 10drvC1 and 10drvC2 which state the port module 10DV should be in, based on its evaluation or the user's instructions. Then, the driver circuits 10drvC1 and 10drvC2 can respectively drive the port devices 10DV1 and 10DV2 (the actuators) according to the control message Mctr provided by the controller 10CTR to set the port module 10DV to a specific state. Since the controller 10CTR knows or has information about the state that the port module 10DV should be in or is currently in, the equalizer 10EQ of the controller 10CTR can use the information about the state of the port module 10DV (such as the control message Mctr) and select or adopt a corresponding/appropriate equalization curve (such as EQCV ₁ ) from the equalization curves EQCV ₁ to EQCV _M according to the information provided by the controller 10CTR to adjust or equalize an input signal Sin.

After the equalizer 10EQ converts the input signal Sin into the adjustment/equalization input signal SIN according to the selected equalization curve (e.g., EQCV ₁ ), the driving circuit 10drvC can drive the sound generating device 10SPD according to the adjustment/equalization input signal SIN sent from the output terminal of the equalizer 10EQ. Therefore, the sound generating device 10SPD generates sound in a manner corresponding to the adjustment/equalization input signal SIN (e.g., SS1 in FIG. 8 ). Since the equalizer 10EQ has enhanced the signal strength in order to overcome the low-frequency attenuation (e.g., when the port module 10DV is operated in a double-open state), the low-frequency sound generated by the sound generating device 10SPD is also enhanced.

The term "(open) state" is different from the term "mode". The state of all port devices of the sound system 10 (i.e., the state of the port module 10DV) may be affected by the mode of one of the port devices, and the modes of each port device together may constitute/define the state of the port module 10DV. However, in terms of a single port device configuration, the term "(open) state" and the term "mode" may be used interchangeably.

In other words, the port device 10DV1 or 10DV2 can be operated in one of the open mode, the closed mode and the comfort mode. The open, closed and comfort modes of the port device 10DV1/10DV2 can constitute/define multiple states of the port module 10DV.

For example, a port device has three different modes, and a single port device configuration has three different states. FIG. 5 is a schematic diagram of three different modes/states of a port device/module 50DV according to an embodiment of the present invention. The port device 10DV1 or 10DV2 can be implemented by the port device 50DV. The port device 50DV may include flaps 511Fa, 511Fb and actuators 512Ca, 512Cb. The actuators 512Ca, 512Cb are driven by a drive circuit 50drvC and are respectively disposed on the flaps 511Fa and 511Fb that are opposite to each other. The flap 511Fa or 511Fb can be actuated by the actuating portion 512Ca or 512Cb to bend, swing or tilt upward or downward, which is beneficial to achieve dynamic ventilation or dynamic opening 513vnt.

When the flap 511Fa is actuated to bend upward and the flap 511Fb is actuated to bend downward (or the flaps 511Fa and 511Fb swing in opposite directions) to form a vent 513vnt having a first opening width, the vent device 50DV is considered to be operated in the open mode/state (shown in FIG. 5(a)). Therefore, an airflow channel is formed between the volume 530chmF (connected to or to be connected to the ear canal) and the volume 530chmB (connected to or to be connected to the external surrounding environment) to release or reduce the pressure caused by the closing effect. Accordingly, the frequency response curve (e.g., the thick solid line in FIG. 2) decreases significantly (towards low frequencies).

The distance between the two end points (tips) of the two flaps (511Fa and 511Fb) can be evaluated or used as the above-mentioned opening width, or can be regarded as a kind of opening degree.

When the flaps 511Fa and 511Fb are aligned substantially parallel to each other (or actuated to align) to close or seal the vent 513vnt, the vent device 50DV is considered to be operating in a closed mode/state (as shown in FIG. 5(b)), and the vent 513vnt has a second opening width. In the closed mode, the vent device 50DV can prevent background noise from entering the ear canal to improve passive isolation. The volumes 530chmF and 530chmB are almost unconnected to avoid a significant drop in the sound pressure level at lower frequencies (e.g., the thin solid line in FIG. 2).

When the flaps 511Fa and 511Fb are neutrally or loosely suspended and/or tilted downward (to below the horizontal plane relative to their anchoring ends), the vent device 50DV is considered to be operating in the comfort mode/state (as shown in Figure 5(c)), and the vent 513vnt has a third opening width. The first opening width is the largest of the three, and the second opening width is narrower than the third opening width. In other words, the opening degree of the comfort mode is between the opening degree of the open mode and the opening degree of the closed mode. The smaller vent 513vnt formed in the comfort mode can relieve the pressure accumulated in the ear canal, improve comfort and save energy. The frequency response curve corresponding to the comfort mode/state (such as the thick solid line in Figure 2) shows a trend of gradually decreasing towards the low-frequency end of the spectrum.

In the comfort mode, the vent device 50DV is in its lowest power state because the actuator of the flap is low powered or not powered. For example, the drive voltage applied to the actuator may be 0V or the actuator may be floating. The position of the two (vent) flaps forms a small (leakage) opening to relieve pressure buildup in the ear canal, thereby improving the comfort of wearing the earbud for long periods of time.

Operation in comfort mode reduces ear canal pressure to extend earbud usage, reduces static pressure buildup in the occluded ear canal, and reduces earwax due to lower temperature and humidity in the ear canal. The mouthpiece 50DV can be switched to closed mode when the user prefers increased passive isolation to reduce ambient noise and/or to concentrate on listening to the media.

On the other hand, occluded ears make the ears more sensitive to sounds, for example, by 25dB at 250Hz. The occlusion effect produces a muffled, loud sound in the user's brain for the user's voice, footsteps and chewing. Operating in comfort mode creates a leakage path, which reduces the intensity level of the occlusion effect and limits the impact on the battery life of the earbuds. The reduction in leakage in comfort mode improves the low-frequency bass perception during music playback compared to open mode. To completely eliminate the occlusion effect, the vent device 50DV can be switched to open mode, but at a higher power consumption.

Additionally, operating in Comfort mode increases awareness of the environment. In Comfort mode, speech clarity is improved compared to Off mode by providing physical pass-through for a more natural one-on-one conversation, rather than digitally adjusting as most active pass-through features use microphones, digital signal processor (DSP) technology and speakers to re-broadcast and enhance the human voice. In Comfort mode, safety is improved compared to Off mode by providing direct and more natural pass-through of ambient and situational noises (such as oncoming cars or sirens). When the user prefers to increase passive isolation in order to reduce ambient noise and/or concentrate on listening to the media, the Portal Device 50DV can be switched back to Off mode.

In short, for a single port device configuration, there are three different states. The equalizer 10EQ can obtain three equalization curves corresponding to the three different states of the only port device (such as 50DV) of the sound system.

In one embodiment, for a dual-port device configuration, there are nine different states: each port device (e.g., 10DV1 or 10DV2) can be operated in one of three modes (e.g., open mode, closed mode, and comfort mode); therefore, when the two port devices 10DV1 and 10DV2 are operated simultaneously, the two port devices 10DV1 and 10DV2 can be operated in a total of 3×3=9 different states (e.g., both-open status, both-closed status, both-comfort status, one-open-one-close status, or one-close-one-open status). The equalizer 10EQ can obtain nine equalization curves (eg, EQCV ₁ to EQCV ₉ ) in nine different states for use in a channel module (eg, 10DV).

In one embodiment, for a dual-port device configuration, the operation of two port devices (e.g., 10DV1 and 10DV2) can be distinguished or simplified into three different states: a dual-open state, a dual-closed state, and an only-one-open status. In the dual-open state, the ports of the port devices 10DV1 and 10DV2 are both open and operated in an open mode. In the only-one-open state, one of the port devices 10DV1 and 10DV2 is operated in an open mode, while the other is operated in a closed mode or a comfort mode. In the dual-closed state, the port devices 10DV1 and 10DV2 are both operated in a closed mode or both operated in a comfort mode. The equalizer 10EQ can obtain three equalization curves (eg, EQCV ₁ to EQCV ₃ ) corresponding to three different states.

Using only three equalization curves (e.g., EQCV ₁ -EQCV ₃ ) for two port devices implicitly assumes that the difference between the equalization curves for the off mode/state and the equalization curves for the comfort mode/state is negligible, and that the equalization curves for the on-off state and the off-on state are indistinguishable. For example, when port devices 10DV1 and 10DV2 are symmetrically arranged and identical port devices are manufactured in the same manner, the frequency response corresponding to the on-off state and the frequency response corresponding to the off-on state may be indistinguishable regardless of which of port devices 10DV1 and 10DV2 is operated in the on mode.

As described above, the total number of equalization curves (e.g., EQCV ₁ -EQCV _M ) may be equal to or related to the total number of possible states of the port module 10DV. For example, corresponding to three different states of a single-port device configuration, the equalizer 10EQ may obtain three equalization curves. Corresponding to three (or nine) different states of a dual-port device configuration, the equalizer 10EQ may obtain three (or nine) equalization curves.

In one embodiment, the total number of equalization curves (e.g., EQCV ₁ -EQCV _M ) may be related to at least the total number of port devices, the total number of modes of a single port device, or the music style. For example, for two port devices 10DV1 and 10DV2, each having three different modes (e.g., open mode, closed mode, and comfortable mode), the equalizer 10EQ may access ³² different equalization curves.

In one embodiment, the total number of equalization curves or the total number of states that the port module 10DV can perform can be at least three and greater than two. In other words, the types of low-frequency roll-off that the sound system 10 can compensate for go beyond simply 2 types either-ON-or-OFF scenarios, meaning that the sound system 10 can compensate/equalize more than two types of low-frequency roll-off (one type corresponding to the on mode and the other type corresponding to the off mode). This is because 1) the port device has the option of operating in the (third) comfort mode; and/or 2) the port module having multiple port devices has the option of operating in more than two states.

FIG. 6 is a schematic diagram of a wearable sound device 60IE according to an embodiment of the present invention, which illustrates the configuration of a port device and a sound generating device. The wearable sound device 60IE (e.g., an in-ear sound device, an earphone, or a hearing aid) may include port devices 60DV1, 60DV2, a sound generating device 60SPD, and a driving circuit for the port devices 60DV1, 60DV2 or the sound generating device 60SPD, all of which may be disposed in a housing 600. The port devices 10DV1, 10DV2 and the sound generating device 10SPD may be implemented using the port devices 60DV1, 60DV2 and the sound generating device 60SPD.

In FIG. 6 , since two port devices (i.e., 60DV1 and 60DV2 ) are provided in one wearable sound device (i.e., 60IE), the total number of the port devices is equal to 2. However, the present application is not limited thereto. A port module including n port devices may be provided in one wearable sound device (i.e., 60IE), and the total number of the port devices may be equal to n.

The total number of equalization curves (e.g., EQCV ₁ -EQCV _M ) corresponding to the states of n port devices of a port module may be M, where n and M are positive integers (e.g., 1, 2, or 3). As described above, M may not be a function of n (e.g., M=3 ⁿ , M=n+1, M=p×c ⁿ , or M=(n+1)×p) or may be related to n (e.g., M≥n), where c and p are positive integers, c represents the total number of modes of a port device (e.g., open mode, closed mode, and comfort mode), and p represents a coefficient and may be related to the music style. It is worth noting that a port module including only one port device is also within the scope of the present application.

In one embodiment, the equalization curve (e.g., EQCV ₁ -EQCV _M ) can be automatically created or adjusted by a program or manually by a user. For example, the sound system 10 can use software and automatically generate or calculate the equalization curve according to a preset or algorithm to compensate for the (low-frequency) roll-off of different states of the port module. The sound system 10 can pre-analyze all possible states of a wearable sound device (i.e., 60IE) and generate/adjust the equalization curve for subsequent optimization of audio quality.

Alternatively, the user may use a graphical equalizer GUI application with a series of physical or virtual sliders to control the volume of each frequency band. By manually adjusting the sliders to set a customized equalization curve, the user can improve the overall audio quality according to personal preferences and needs. The curve graphically displayed by the sliders may correspond to an equalization curve (e.g. EQCV ₁ ) that processes the (low frequency) roll-off of different states of the port module. Alternatively, the user may use a parametric equalizer application to manipulate the parameters of each frequency band (e.g. center frequency, bandwidth or amplitude) to create a customized equalization curve (e.g. EQCV ₁ ) that processes the (low frequency) roll-off of different states of the port module. Automatically or manually created equalization curves can be stored in memory circuits or lookup tables.

In one embodiment shown in Fig. 6, the port devices 60DV1 and 60DV2 may be symmetrically arranged. When the port device 60DV1 or 60DV2 is operated in the open mode and its port is opened, air may flow in the direction of the corresponding dotted arrow.

Please refer to FIGS. 1 and 6 . The controller 10CTR may or may not be disposed in the wearable sound device 60IE. The communication device 60DV1, 60DV2, or the sound generating device 60SPD may be communicatively coupled to the controller 10CTR via a wireless/wired connection to transmit signals (e.g., control messages Mctr or adjustment/equalization input signals SIN) between the controller 10CTR and the communication device 60DV1, 60DV2, or the sound generating device 60SPD. The wireless connection may be, for example, a short-distance connection such as IEEE 802.15.4 (ZigBee) or Bluetooth, a medium-distance connection such as Wireless Fidelity (Wi-Fi), or a long-distance connection such as Long Term Evolution (LTE) or the fifth generation mobile communication technology (5G). The controller 10CTR may be disposed in an electronic device (such as a smart phone, tablet computer, or other device that can meet fast computing requirements and has a large battery capacity). By utilizing the computing resources of the electronic device, all (computing) processing can be offloaded to the electronic device to reduce the complexity, power consumption, or extend the battery life of the wearable audio device 60IE.

The controller 10CTR may receive status instructions regarding the status of a port module (e.g., 10DV) from other devices via a wireless/wired connection (e.g., Bluetooth). For example, a user may provide information/instructions regarding the status of a port module to the controller 10CTR via a GUI of a device (including the controller 10CTR or communicatively coupled to the controller 10CTR) so that the user may dynamically open/close the port. Alternatively, a sensor may notify the controller 10CTR of the status of the port module so that the port is dynamically opened/closed.

The controller 10CTR that indirectly or directly controls the port devices (e.g., 60DV1 and 60DV2) or the sound generating device (e.g., 60SPD) may operate in the digital domain. The equalizer 10EQ provided in the controller 10CTR may operate in the digital domain. The equalizer 10EQ may be an equalization filter or include a set of (programmed or programmable) filters. In one embodiment, the controller 10CTR may be implemented as a system on a chip (SoC), but is not limited thereto.

The driving circuit 10drvC for driving the sound generating device (eg, 60SPD) may include an analog amplifier or a digital-to-analog converter (DAC).

The driving circuit (e.g., 10drvC1 or 10drvC2) used to drive the port device (e.g., 60DV1 or 60DV2) may include an (analog) amplifier. The driving circuit (e.g., 10drvC1 or 10drvC2) may provide a driving voltage to the port device (e.g., 60DV1 or 60DV2) according to the control message Mctr sent by the controller 10CTR, so that the port device (e.g., 60DV1 or 60DV2) operates in the mode specified by the control message Mctr. In one embodiment, the driving circuit 10drvC1 or 10drvC2 may include the driving circuit disclosed in U.S. Patent Application No. 18/366,637, but is not limited thereto.

In one embodiment, the driver circuit 10drvC, 10drvC1 or 10drvC2 may be provided or not provided in the wearable sound device according to actual needs. In one embodiment, the driver circuit 10drvC and the sound producing device 10SPD may be integrated into a sound producing package. Similarly, the port device (e.g., 10DV1) and its corresponding driver circuit (e.g., 10drvC1) may be integrated into a port package. The sound producing package and the port package may both be provided in the wearable sound device.

The vent device (e.g., 60DV1 or 60DV2) may be a micro-electromechanical system (MEMS) device. The sound generating device (e.g., 60SPD) may be or include any type of electroacoustic transducer (e.g., MEMS device), any type of speaker, or a combination thereof. For example, the sound system or wearable sound device of the present application may adopt the vent device or sound generating device made of MEMS disclosed in U.S. Patent Application Nos. 17/842,810, 17/344,980, 17/344,983, and 17/720,333, but is not limited thereto.

For example, as disclosed in U.S. Patent Application Nos. 17/842,810, 17/344,980 and 17/344,983, the vent device of the vent module may include a membrane structure having a slit formed thereon so that the slit forms a vent connecting the volume of the wearable audio device (and/or the volume of the ear canal) with the surrounding environment.

U.S. Patent Application Nos. 17/842,810, 17/344,980 and 17/344,983 also disclose an acoustic transducer that may include a membrane structure that can be actuated to form at least one port (to connect the volume of the wearable sound device or ear canal to the environment) and perform acoustic conversion (e.g., generate sound). An acoustic transducer that can form a port and generate sound using an equalized input signal is also within the scope of the present application.

In one embodiment, the membrane structure of the acoustic transducer capable of forming a port and generating sound may have a structure similar to the petal shown in FIG. 5, but this is only an example and not limited thereto. The acoustic transducer may include a first membrane for forming a port (as a port device) and a second membrane for generating sound (as a sound generating device), and the first membrane and the second membrane together may be regarded as a membrane structure. From another point of view, the port device 10DV1/10DV2 and the sound generating device 10SPD shown in FIG. 1 together may be regarded as the acoustic transducer of the present application.

In one embodiment, the wearable audio device may include only a port device, which is also within the scope of the present application.

As long as the equalized input signal is used to generate sound in the wearable sound device to offset the roll-off caused by at least one port corresponding to a plurality of opening degrees, so that the perceived sound has a substantially consistent (amplitude) frequency response, the requirements of this application are met and within the scope of this application.

FIG. 7 is a schematic diagram of a sound generating device 70SPD according to an embodiment of the present invention. The sound generating device 10SPD or 60SPD may be implemented by the sound generating device 70SPD. The sound generating device 70SPD may include a two-way speaker, which includes sound generating sub-devices 70SPDa and 70SPDb. The sound generating sub-devices 70SPDa and 70SPDb may be used as a tweeter and a woofer, respectively. The sound generating sub-device 70SPDa may be implemented by a MEMS device (such as disclosed in U.S. Patent Application No. 17/720,333). The sound generating sub-device 70SPDb may be implemented by an audio dynamic driver or a moving-coil speaker. Preferably, the sound generating sub-device 70SPDb used as a woofer can provide/generate a higher volume (compared to a tweeter) or sufficient low-frequency acoustic driving capability to facilitate low-frequency acoustic equalization.

FIG. 8 is a schematic diagram of the signal transmission mechanism and the sound propagation mechanism of the embodiment of the present invention. After the equalizer 10EQ responds to the input signal Sin and outputs the adjusted/equalized input signal SIN after adjustment/equalization according to the selected equalization curve (e.g., EQCV ₁ ), the sound generating device 10SPD can generate the sound SS1. When the sound SS1 propagates from the sound generating device 10SPD to the eardrum of the listener, it may be reshaped/distorted and transformed into the sound SS2 by passing through or encountering the outer shell/casing (e.g., 600) of the wearable sound device (e.g., 60IE). Compared with the sound SS1, the sound SS2 may have a low-frequency roll-off due to the state of the port module (e.g., 10DV). However, since the low frequency roll-off has been compensated/cancelled by the equalizer 10EQ, the acoustic effect of the sound SS2 can finally meet expectations.

Referring to Figures 1 and 8, when the port devices 10DV1 and 10DV2 are switched from the double closed state to the double open state in response to the control message Mctr sent by the controller 10CTR, the previously closed ports of the port devices 10DV1 and 10DV2 are opened. Accordingly, the acoustic characteristics of the outer shell/casing of the wearable sound device (such as 60IE) are changed, which may cause an increase in the low frequency roll-off of the sound SS2.

At the same time, based on the dual-on state indicated by the control message Mctr, the equalizer 10EQ switches from one equalization curve (e.g., 4EQCV _M ) to another equalization curve (e.g., 4EQCV ₁ ) to process the input signal Sin differently in response to different states. The adjusted/equalized input signal SIN can be divided into a first frequency component (e.g., a low-frequency component) and a second frequency component (e.g., a mid-frequency component), and the equalizer 10EQ can adjust the adjusted/equalized input signal SIN corresponding to the dual-on state and the adjusted/equalized input signal SIN corresponding to the dual-off state in different ways. Therefore, the difference between the first frequency component corresponding to the double-open state and the first frequency component corresponding to the double-closed state may be different from (or greater than) the difference between the second frequency component corresponding to the double-open state and the second frequency component corresponding to the double-closed state; the difference between the first frequency component and the second frequency component corresponding to the double-open state may be different from (or greater than) the difference between the first frequency component and the second frequency component corresponding to the double-closed state.

For example, the equalizer 10EQ may tend to attenuate the first frequency component less in the double-on state than in the double-off state, so the sound generating device 10SPD tends to make the first frequency sound (e.g., low-frequency sound) of the sound SS1 louder in the double-on state. Although the first frequency sound of the sound SS1 is stronger, it may be more weakened after being transmitted through the wearable sound device and transformed into the first frequency sound of the sound SS2, but it may be in line with expectations. For example, the acoustic effect of the sound SS2 in the double-off state may be close to the acoustic effect of the sound SS2 in the double-on state.

In other words, for the dynamic port of the port device 10DV1 or 10DV2, the equalizer 10EQ dynamically performs switchable equalization to achieve the desired audio balance. The change of the equalizer 10EQ, the sound transmission path of the wearable audio device and the ear canal may cause the acoustic effect of the sound SS2 observed in one state (e.g., the double open state) to be similar to the acoustic effect of the sound SS2 observed in another state (e.g., the double closed state).

Frequency response may involve actuating the sound generating device 10SPD with a carefully designed input signal and measuring the resulting sound at the listener's eardrum (or in a closed ear canal simulator such as a 711 coupler).

The equalization operation can be summarized as the equalization process 90 shown in FIG. 9. The equalization process 90 may include the following steps:

Step 900: Obtaining a state of a port module among a plurality of states, wherein the port module forming at least one port operates between a plurality of states corresponding to a plurality of opening degrees.

Step 902: Generate an equalized input signal according to the state.

The details of the equalization process 90 can be found in the above paragraphs and will not be described in detail here.

For details or modified embodiments of the wearable sound device, sound generating device, port device, drive circuit or controller, reference may be made to U.S. Patent Application Nos. 17/842,810, 17/344,980, 17/344,983, 17/720,333, 18/172,346, 18/303,599, 18/366,637, 18/530,235 or U.S. Provisional Patent Application No. 63/320,703, the disclosures of which are incorporated herein by reference in their entirety and become part of this specification.

The terms "first", "second", etc. mentioned throughout the specification are only used to distinguish different components, and do not impose any restrictions on the order, priority, time sequence of method execution, or that all components must exist. The embodiments described above can be combined in various ways without conflict.

In summary, the present application recognizes that different states of the port device may have different effects on the audio quality. Therefore, the present application provides multiple (e.g., more than two) equalization curves corresponding to different states of the port device. The equalizer of the present application can select the equalization curve for the current state, expected state, or future state of the port device from the equalization curve to improve the audio experience or enhance the sound quality. The above is only a preferred embodiment of the present invention, and all equivalent changes and modifications made according to the patent scope of the present invention application shall fall within the scope of the present invention.

10: Sound system 10CTR: Controller 10drvC, 10drvC1, 10drvC2, 50drvC: Driving circuit 10DV: Port module 10DV1, 10DV2, 50DV, 60DV1, 60DV2: Port device 10EQ: Equalizer 10SPD, 60SPD, 70SPD: Sound generating device 511Fa, 511Fb: Petal 512Ca, 512Cb: Actuator 513vnt: Port 530chmF, 530chmB: Volume 600: Housing 60IE: Wearable sound device 70SPDa, 70SPDb: Sound generating sub-device 90: Equalization process 900, 902: Steps EQCV ₁ to EQCV _M , 4EQCV ₁ ,4EQCV _M :Equalization curve Mctr:Control message SIN:Equalization input signal Sin:Input signal SS1,SS2:Sound

FIG. 1 is a schematic diagram of a sound system according to an embodiment of the present invention. FIG. 2 is a schematic diagram of a frequency response corresponding to a single-port device configured without equalization or before equalization according to an embodiment of the present invention. FIG. 3 is a schematic diagram of a frequency response corresponding to a dual-port device configured without equalization or before equalization according to an embodiment of the present invention. FIG. 4 is a schematic diagram of an equalization curve according to an embodiment of the present invention. FIG. 5 is a schematic diagram of three different modes/states of a port device/module according to an embodiment of the present invention. FIG. 6 is a schematic diagram of a wearable sound device according to an embodiment of the present invention. FIG. 7 is a schematic diagram of a sound generating device according to an embodiment of the present invention. FIG. 8 is a schematic diagram of a signal transmission mechanism and a sound propagation mechanism according to an embodiment of the present invention. Figure 9 is a schematic diagram of the equalization process of an embodiment of the present invention.

10: Sound system

10CTR: Controller

10drvC, 10drvC1, 10drvC2: driving circuit

10DV: Port module

10DV1,10DV2: port device

10EQ: Equalizer

10SPD: Sound generating device

EQCV ₁ ~EQCV _M , 4EQCV ₁ , 4EQCV _M : Equalization curve

Mctr: Control message

SIN: equalized input signal

Sin: input signal

Claims (28)

A wearable sound device comprises: a port module, comprising at least one port device, for forming at least one port to connect the volume of the wearable sound device with the environment; and a sound generating device, for generating sound according to an equalized input signal; wherein the port module operates between a plurality of states corresponding to a plurality of opening degrees; wherein a controller generates the equalized input signal according to one of the plurality of opening degrees to offset the roll-off caused by the at least one port. A wearable sound device as described in claim 1, wherein the sound perceived in a first state with a minimum opening corresponds to a first frequency response; wherein the sound perceived in a second state with a maximum opening corresponds to a second frequency response; wherein the difference between the first frequency response and the second frequency response is less than a specific threshold. A wearable audio device as described in claim 1, wherein a port device of the port module operates in one of a plurality of modes, and the plurality of modes of the at least one port device constitute the plurality of states of the port module. A wearable audio device as described in claim 3, wherein the plurality of modes include an off mode, an on mode or a comfort mode. A wearable audio device as described in claim 4, wherein an opening degree of the comfort mode is between an opening degree of the open mode and an opening degree of the closed mode. A wearable sound device as described in claim 4, wherein the port device includes a first flap and a second flap; wherein, in the open mode, the first flap is actuated to bend upward, and the second flap is actuated to bend downward; wherein, in the closed mode, the first flap and the second flap are actuated to be parallel to each other; wherein, in the comfort mode, the first flap and the second flap are suspended below a horizontal plane corresponding to an anchor end of the first flap and an anchor end of the second flap. A wearable audio device as described in claim 1, wherein the controller generates the equalized input signal using a first equalization curve of the plurality of equalization curves according to a first state of the communication module. A wearable audio device as described in claim 7, wherein the controller replaces the first equalization curve with a second equalization curve of the plurality of equalization curves in response to a control message, the control message being about switching from the first state to a second state. A wearable audio device as described in claim 7, wherein the first state is determined by the controller or communicated to the controller from a user or a device communicatively coupled to the controller. A wearable audio device as described in claim 7, wherein a control message regarding the first state of the port module is received by the controller or transmitted to the at least one port device via a wireless connection or a wired connection. A wearable audio device as described in claim 7, wherein each of the plurality of equalization curves is created or edited parametrically, graphically, automatically or manually corresponding to one of the plurality of states of the communication module. A wearable audio device as described in claim 7, wherein the total number of the plurality of equalization curves is at least related to the total number of the at least one port device or the total number of modes of one of the at least one port device. A wearable audio device as described in claim 1, wherein the controller is disposed within the wearable audio device. A wearable audio device as described in claim 1, wherein the controller is disposed in an electronic device communicatively coupled to the wearable audio device. A wearable sound device as described in claim 1, wherein the equalized input signal is transmitted from the controller to the sound generating device via a wireless connection or a wired connection. A wearable audio device as described in claim 1, wherein the controller generates the equalized input signal using a plurality of equalization curves corresponding to the plurality of states. A wearable audio device as described in claim 1, wherein the number of the plurality of states is greater than 2. A wearable sound device as described in claim 1, wherein a port device of the port module includes a membrane structure, the membrane structure is formed with a slit, and one of the at least one ports is formed by the slit. A wearable audio device as described in claim 1, wherein the sound generating device includes a first sound generating sub-device used as a tweeter and a second sound generating sub-device used as a woofer. A wearable acoustic device as described in claim 19, wherein the first sound generating sub-device is made of a micro-electromechanical system. A wearable audio device as described in claim 19, wherein the second sound generating sub-device includes an audio dynamic driver or a dynamic speaker. A device, comprising: A controller, used to generate an equalized input signal according to an opening degree of a port module among a plurality of opening degrees; wherein the port module is used to form at least one port and has the plurality of opening degrees; wherein the controller that generates the equalized input signal is used to offset the roll-off caused by the at least one port. The apparatus of claim 22, wherein the controller generates the equalized input signal using a first equalization curve of a plurality of equalization curves based on a first state of the port module. An equalization method for generating an equalized input signal for a sound generating device comprises: Obtaining a state of a port module among a plurality of states, wherein the port module forming at least one port operates between the plurality of states corresponding to a plurality of opening degrees; and Generating the equalized input signal according to the state. The equalization method as described in claim 24 further includes: Using a first equalization curve of the plurality of equalization curves according to a first state of the port module to generate the equalized input signal. The equalization method as described in claim 25 further includes: In response to a control message, switching from the first equalization curve to a second equalization curve of the plurality of equalization curves, the control message being about switching from the first state to a second state. An equalization method as described in claim 25, wherein each of the plurality of equalization curves is created parametrically, graphically, automatically or based on user instructions corresponding to one of the plurality of states of the port module. A wearable sound device, comprising: an acoustic transducer, used to form at least one opening to connect the volume of the wearable sound device with the environment, and used to generate sound according to an equalized input signal; wherein the acoustic transducer operates between a plurality of states corresponding to a plurality of opening degrees; wherein a controller generates the equalized input signal according to one of the plurality of opening degrees to offset the roll-off caused by at least one opening.

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