Method and system for reproducing headphone sound using front and auxiliary speakers

Abstract

The present disclosure relates to methods and systems for reproducing headphone sound using front and auxiliary speakers. A method for reproducing headphone sound using front and auxiliary speakers in an audio system. The method includes arranging a pair of front stereo speakers and a pair of auxiliary speakers in a predetermined configuration near a user's ears, applying a delay to the pair of front speakers or the pair of auxiliary speakers, playing a test audio signal through the pair of front stereo speakers and auxiliary speakers, measuring an interaural level difference (ILD) at the user's ears in a frequency range from about 1 kHz to about 10 kHz to obtain a measured ILD, comparing the measured ILD to a generic ILD representative of headphone-like spatial audio effects, deriving a set of equalization (EQ) settings for the pair of auxiliary speakers to reduce a difference between the measured ILD and the generic ILD, and storing the set of EQ settings for use in the audio system.

Description

Technical Field

[0001] This disclosure generally relates to audio systems, and more specifically to audio systems with front-facing near-ear speakers for reproducing headphone-like experiences through HRTF-based EQ adjustments. Background Technology

[0002] Audio systems have traditionally fallen into two main categories: open-back speaker setups and personal listening devices (such as headphones). Each category has its own advantages and limitations. Headphones are popular for their ability to provide a private, immersive sound experience, typically achieved through a head-related transfer function (HRTF), which simulates a spatial audio environment tailored to each listener. However, prolonged headphone use can lead to discomfort, ear fatigue, and social isolation, as the listener is essentially shut out of external sound.

[0003] On the other hand, speaker systems provide an open listening environment, allowing users to maintain awareness of their surroundings and listen comfortably for extended periods. However, speakers typically lack the privacy and precise spatial cues of headphones, making it difficult to achieve the same level of audio immersion in film and music content, or the precise sound localization necessary for gaming. Typical speaker setups struggle to reproduce the directional sound localization offered by headphones, partly due to the lack of personalized HRTF processing.

[0004] To bridge the gap between speaker systems and headphone experiences, technologies such as surround sound and near-field monitors have been developed. While these technologies offer enhanced spatial audio compared to traditional speakers, they still fall short of achieving the headphone-like immersive soundstage that many listeners crave. Therefore, there remains a desire for an audio system that combines the comfort and openness of speakers with the personalization and spatial immersion of headphones, providing listeners with a more engaging and realistic audio experience while avoiding the drawbacks associated with prolonged headphone use. Summary of the Invention

[0005] In various embodiments, a method is provided for reproducing headphone sound using front speakers and auxiliary speakers in an audio system. The method includes: arranging a pair of front stereo speakers and a pair of auxiliary speakers in a predetermined configuration near a user's ear; applying a delay to the pair of front stereo speakers or the pair of auxiliary speakers; playing a test audio signal through the pair of front stereo speakers and the pair of auxiliary speakers; measuring the interaural level difference (ILD) at the user's ear location in a frequency range of 1 kHz to 10 kHz to obtain a measured ILD; comparing the measured ILD with a generic ILD representing the spatial audio effect of similar headphones; deriving a set of equalization (EQ) settings for the pair of auxiliary speakers to reduce the difference between the measured ILD and the generic ILD; and storing the set of EQ settings for use in the audio system.

[0006] In various embodiments, an audio system is provided for reproducing headphone sound using front stereo speakers and auxiliary speakers. The audio system includes: a pair of front stereo speakers and a pair of auxiliary speakers configured to be placed near a user's ears; a delay module configured to apply a delay to the pair of front stereo speakers or the pair of auxiliary speakers; a storage module configured to store a set of pre-calibrated equalization (EQ) settings; and an audio processing module configured to apply the set of pre-calibrated EQ settings to the pair of auxiliary speakers. The set of pre-calibrated EQ settings is derived from a comparison of a measured binaural level difference (ILD) of the audio system with a general ILD, and is pre-calibrated to reduce the difference between the measured ILD and the general ILD. Attached Figure Description

[0007] Figure 1 This is a flowchart illustrating a method for reproducing headphone sound using front and auxiliary speakers, according to some embodiments.

[0008] Figure 2 This is a diagram illustrating the binaural level difference as a function of frequency, according to some embodiments.

[0009] Figure 3 This is a system diagram of an audio system for reproducing headphone sound using front and auxiliary speakers, according to some embodiments.

[0010] Figure 4 This is a system diagram of an audio system for reproducing headphone sound using front and auxiliary speakers, according to some embodiments. Detailed Implementation

[0011] The following detailed embodiments are merely exemplary in nature and are not intended to limit the scope of this disclosure or its applications and uses. Furthermore, they are not intended to be limited by any theories presented in the foregoing background information or the following detailed embodiments. The purpose of the various embodiments is to provide methods and systems for reproducing headphone sound using front and auxiliary speakers to replicate the advantages of headphones while avoiding their associated discomfort and other problems.

[0012] refer to Figure 1 The diagram illustrates a flowchart (100) depicting a method for reproducing headphone sound using front and auxiliary speakers according to various embodiments. In step 110, a pair of front stereo speakers and a pair of auxiliary speakers are arranged in a predetermined configuration near the user's ears. The pair of front stereo speakers is positioned in front of the user and is set to face the user directly. These speakers are preferably designed as soundbars and ideally placed in the near field, at a distance of approximately 100cm to 140cm from the user. The pair of auxiliary speakers is near-ear type and can be implemented in various forms, such as neckband speakers, headband speakers, chair speakers, eyeglass frames, or headwear (e.g., baseball caps, fedoras, or beanies). To enhance comfort, low-frequency components of the audio output from the pair of auxiliary speakers are removed to avoid uncomfortable vibrations to the user's body. This is preferably achieved by using a high-pass filter. Preferably, the high-pass filter removes frequencies below 300 Hz.

[0013] In step 120, a delay is applied to the pair of front stereo speakers or the pair of auxiliary speakers to synchronize the time it takes for the audio to reach the user's ears. The goal is to ensure that the time it takes for sound to travel from both sets of speakers to the user's ears is approximately the same, allowing a tolerance of up to ±0.5 ms. The implementation of the delay depends on the connection type between the pair of auxiliary speakers and / or the pair of front stereo speakers to the audio system. The pair of auxiliary speakers and / or the pair of front stereo speakers can be connected to the audio system via wired or wireless means. The delay can be determined by calculating the difference in the time it takes for sound to travel from the two sets of speakers to the user's ears. If the time it takes for sound to travel from the pair of front stereo speakers to the user's ears is longer than the time it takes for sound to travel from the pair of auxiliary speakers to the user's ears, then a delay is applied to the pair of auxiliary speakers. If the time it takes for sound to travel from the pair of auxiliary speakers to the user's ears is longer than the time it takes for sound to travel from the pair of front stereo speakers to the user's ears, then a delay is applied to the pair of front stereo speakers. The time it takes for sound to travel from the pair of front stereo speakers and the pair of auxiliary speakers to the user's ears is affected by the physical distance between the speakers and the user, as well as any wireless transmission delay. For example, Bluetooth 5.4 with the LC3 codec typically introduces a delay of 20-40ms, while Bluetooth aptX Low Latency introduces a delay of approximately 30-40ms. Actual delay may also vary depending on the manufacturer's specific implementation. In one embodiment, the delay can be determined by measurement. A test audio signal is played through the pair of front stereo speakers, and the first time it takes for the test audio signal to reach the user's ears is measured. The test audio signal is then played through the pair of auxiliary speakers, and the second time it takes for the test audio signal to reach the user's ears is measured. For example, a head and torso simulator or binaural microphones can be used for measurement. The delay is then determined by calculating the difference between the first and second times. If the first time is longer than the second time, the delay is applied to the pair of auxiliary speakers; if the second time is longer than the first time, the delay is applied to the pair of front stereo speakers. This method of determining delay by measurement takes into account both the physical distance between the speakers and the user and any transmission delay. In one embodiment, the delay can be determined by calculation. The first time it takes for sound waves to reach the user's ear from the pair of front stereo speakers is calculated based on the physical distance and speed of sound from the pair of front stereo speakers, and also based on any wireless delay if the pair of front stereo speakers are wirelessly connected to the audio system. The second time it takes for sound waves to reach the user's ear from the pair of auxiliary speakers is calculated based on the physical distance and speed of sound from the pair of auxiliary speakers, and also based on any wireless delay if the pair of auxiliary speakers are wirelessly connected to the audio system. The delay is determined by calculating the difference between the first and second times.If the first time interval is longer than the second time interval, the delay is applied to the auxiliary speakers; if the second time interval is longer than the first time interval, the delay is applied to the front stereo speakers. Typically, it can be assumed that the front stereo speakers are approximately 100cm to 140cm from the user's ear. The difference in the time required for the sound waves to reach the user's ear can also be determined as follows: first, calculate the difference between the physical distance from the front stereo speakers to the user's ear and the physical distance from the auxiliary speakers to the user's ear; then, calculate the time difference using the speed of sound, and finally consider the wireless delay (if any). In one example, the front stereo speakers are connected to the audio system via a wired connection, while the auxiliary speakers are wirelessly connected to the audio system via Bluetooth LE audio in broadcast mode with a delay of 20ms. The distance from the front stereo speakers to the user's ear is 120cm (the midpoint between 100cm and 140cm). The distance from the auxiliary speakers to the user's ear is 20cm. The speed of sound is taken as 343 m / s. Calculations show that a 100cm physical distance difference requires approximately 3ms of delay (which will be applied to the auxiliary speakers). Considering a 20ms wireless delay (which needs to be applied to the front stereo speakers), in this example, a 17ms delay will be applied to the front stereo speakers.

[0014] In step 130, the test audio signal is played through the pair of front stereo speakers and the pair of auxiliary speakers, and in step 140, the binaural level difference (ILD) at the user's ear position in the frequency range of 1 kHz to 10 kHz is measured to obtain the measured ILD. For example, the ILD can be measured at the user's ear position using a head and torso simulator or binaural microphones. In step 150, the measured ILD is compared with a generic ILD representing the spatial audio effect of headphones, and in step 160, a set of equalization (EQ) settings for the pair of auxiliary speakers is derived to reduce the difference between the measured ILD and the generic ILD. The EQ settings are derived by adjusting the EQ settings so that the difference between the measured ILD and the generic ILD within a specified frequency range (e.g., 1 kHz to 10 kHz) does not exceed a predetermined threshold of approximately ±5 dB. The generic ILD can be obtained by directing a pair of reference stereo speakers toward the user's ear, playing the test audio signal through the pair of reference stereo speakers, and measuring the ILD at the user's ear position in the frequency range of 1 kHz to 10 kHz. The generic ILD can also be obtained from a generic database by extracting the ILD from the HRTF data. Generic databases can be, for example, the CIPIC HRTF database, the ARI HRTF database, the Acoustic Spatial Orientation Format (SOFA), the MIT KEMAR HRTF database, and the OpenSL HRTF database.

[0015] In step 170, the set of EQ settings is stored (and / or saved) for use by the audio system. By applying delay and equalization (EQ) adjustments, the audio system reproduces the headphone-like sound experience during playback using the pair of front stereo speakers and the pair of auxiliary speakers. Advantageously, the audio system requires less computationally intensive processing methods (such as delay and equalization (EQ) adjustments) to achieve the headphone-like sound experience, thus eliminating more complex and computationally intensive processing methods (such as binaural rendering or real-time HRTF processing). By focusing on aligning sound arrival times through simple delay adjustments and optimizing spectral balance through pre-calibrated EQ settings, the system effectively reproduces the binaural cues necessary for spatial audio perception. This simplified approach minimizes the use of hardware and / or software, reduces latency, and ensures compatibility with various morphological factors of the pair of auxiliary speakers while maintaining high-quality audio output. Advantageously, the audio system is designed to work with standard stereo audio sources and does not rely on proprietary multichannel audio formats. This simplifies integration with a wide range of audio devices and content, as stereo is the most commonly used audio format across media platforms. By utilizing delay and equalization adjustments, the system effectively creates a spatial audio experience without the need for complex surround sound encoding or decoding, making it easier to use, more cost-effective, and universally compatible with existing audio sources.

[0016] Although the steps in the flowchart are given sequentially, it should be understood that some steps may be executed concurrently or in a different order. The described steps may be implemented in hardware, software, firmware, or any combination thereof.

[0017] refer to Figure 2 The diagram (200) illustrates the binaural level difference (ILD) as a function of frequency according to various embodiments. The universal ILD is shown as curve 210. The measured ILD is shown as curve 220. After a set of EQ settings are derived and applied, the final ILD is shown as curve 230. The difference is primarily observed in the 1 kHz to 10 kHz range, within which the final ILD is more similar to the universal ILD after applying the derived EQ settings. It can be seen that the difference between the measured ILD and the universal ILD in the 1 kHz to 10 kHz frequency range does not exceed a predetermined threshold of approximately ±5 dB.

[0018] refer to Figure 3The diagram illustrates a system diagram of an audio system (300) for reproducing headphone sound using front speakers (310) and auxiliary speakers (320) according to various embodiments. The audio system (300) includes a pair of front stereo speakers (310) and a pair of auxiliary speakers (320) configured to be placed near the ears (332a, 332b) of a user (330). In one embodiment, the audio system (300) may include a subwoofer (340) or an audio hub (not shown) connected via wired or wireless means (350, 360) to the pair of front stereo speakers (310) and the pair of auxiliary speakers (320). The audio system (300) includes a delay module (342) configured to apply a delay to the pair of front stereo speakers (310) or the pair of auxiliary speakers (320). The audio system (300) also includes a storage module (346) and an audio processing module (348). The storage module (346) is configured to store a set of pre-calibrated equalization (EQ) settings, and the audio processing module (348) is configured to apply the set of pre-calibrated EQ settings to the pair of auxiliary speakers (320). The set of pre-calibrated EQ settings is derived from a comparison of the measured binaural level difference (ILD) of the audio system (300) with a universal ILD, and is pre-calibrated to reduce the difference between the measured ILD and the universal ILD, such as... Figure 2 As previously described in detail. The delay module (342) may alternatively be located within the pair of front stereo speakers (310) or the pair of auxiliary speakers (320). The storage module (346) and the audio processing module (348) may alternatively be located within the pair of auxiliary speakers (320).

[0019] refer to Figure 4The diagram illustrates a system diagram of an audio system (400) for reproducing headphone sound using front speakers (410) and auxiliary speakers (420) according to various embodiments. The audio system (400) includes a pair of front stereo speakers (410) and a pair of auxiliary speakers (420) configured to be placed near the ears (432a, 432b) of a user (430). In one embodiment, the audio system (400) may include the pair of front stereo speakers (410) and the pair of auxiliary speakers (420), wherein the pair of front stereo speakers (410) acts as an audio hub, and the pair of auxiliary speakers (420) is connected to the pair of front stereo speakers (410) via a wired or wireless means (460). The audio system (400) includes a delay module (412) configured to apply a delay to either the pair of front stereo speakers (410) or the pair of auxiliary speakers (420). The audio system (400) also includes a storage module (416) and an audio processing module (418). The storage module (416) is configured to store a set of pre-calibrated equalization (EQ) settings, and the audio processing module (418) is configured to apply the set of pre-calibrated EQ settings to the pair of auxiliary speakers (420). The set of pre-calibrated EQ settings is derived from a comparison of the measured binaural level difference (ILD) of the audio system (400) with a universal ILD, and is pre-calibrated to reduce the difference between the measured ILD and the universal ILD, such as... Figure 2 As previously described in detail. The delay module (412) may alternatively be located within the pair of auxiliary speakers (420), particularly when the delay is applied to the pair of auxiliary speakers (420). The storage module (416) and the audio processing module (418) may be located within the pair of auxiliary speakers (420) instead of the pair of front stereo speakers (410).

[0020] In the audio system (300, 400), the pair of front stereo speakers (310, 410) are located in front of the user (330, 430), positioned directly facing the user (330, 430). These speakers (310, 410) are preferably designed as soundbars and ideally placed in the near-field area, approximately 100 cm to 140 cm from the user (330, 430). The pair of auxiliary speakers (320, 420) are near-ear type and can be implemented in various forms, such as neckband speakers, headband speakers, chair speakers, eyeglass frames, or headwear (e.g., baseball caps, fedoras, or beanies). To enhance comfort, low-frequency components of the audio output are removed from the pair of auxiliary speakers (320, 420) to avoid uncomfortable vibrations to the user's body. This is preferably achieved by using a high-pass filter. Preferably, the high-pass filter removes frequencies below 300 Hz.

[0021] Delay modules (342, 412) apply a delay to either the pair of front stereo speakers (310, 410) or the pair of auxiliary speakers (320, 420) to synchronize the time it takes for audio to reach the user's ears (332a / b, 432a / b). The goal is to ensure that the time required for sound to travel from both sets of speakers to the user's ears (332a / b, 432a / b) is nearly identical, allowing for a tolerance of up to ±0.5 ms. The implementation of the delay depends on the connection type of the pair of auxiliary speakers (320, 420) and / or the pair of front stereo speakers (310, 410). The pair of auxiliary speakers (320, 420) and / or the pair of front stereo speakers (310, 410) can be connected to the audio system (300, 400) via wired or wireless means. The delay can be determined by calculating the difference in the time required for sound to travel from the two sets of speakers to the user's ears (332a / b, 432a / b). If the time required for sound to travel from the pair of front stereo speakers (310, 410) to the user's ears (332a / b, 432a / b) is longer than the time required for sound to travel from the pair of auxiliary speakers (320, 420) to the user's ears (332a / b, 432a / b), then a delay is applied to the pair of auxiliary speakers (320, 420). If the time required for sound to travel from the pair of auxiliary speakers (320, 420) to the user's ears (332a / b, 432a / b) is longer than the time required for sound to travel from the pair of front stereo speakers (310, 410) to the user's ears (332a / b, 432a / b), then a delay is applied to the pair of front stereo speakers (310, 410). The time required for sound to travel from the pair of front stereo speakers (310, 410) and the pair of auxiliary speakers (320, 420) to the user's ears (332a / b, 432a / b) is affected by the physical distance between the speakers and the user (330, 430) and any wireless transmission delay. For example, Bluetooth 5.4 with the LC3 codec typically introduces a delay of 20–40 ms, while Bluetooth aptX Low Latency has a delay of approximately 30–40 ms. Actual delay may also vary depending on the manufacturer's specific implementation. In one embodiment, the delay can be determined by measuring using a delay measurement module. A test audio signal is played through the pair of front stereo speakers (310, 410), and the first time the test audio signal reaches the user's ears (332a / b, 432a / b) is measured. A second time the test audio signal reaches the user's ears (332a / b, 432a / b) is measured, and the test audio signal is played through the pair of auxiliary speakers (320, 420). For example, measurements can be taken using a head and torso simulator or binaural microphones. The delay is then determined by calculating the difference between the first and second times.If the first time is longer than the second time, the delay is applied to the pair of auxiliary speakers (320, 420); if the second time is longer than the first time, the delay is applied to the pair of front stereo speakers (310, 410). This method of determining the delay by measurement takes into account both the physical distance between the speakers and the user (330, 430) and any transmission delay. In one embodiment, the delay can be determined by calculation using a delay calculation module, or it can be pre-calculated during the product design phase. The first time it takes for sound waves to reach the user's ears (332a / b, 432a / b) from the pair of front stereo speakers (310, 410) is calculated based on the physical distance and speed of sound from the pair of front stereo speakers (310, 410) to the user's ears (332a / b, 432a / b), and also based on any wireless delay if the pair of front stereo speakers (310, 410) are wirelessly connected to the audio system (300, 400). The second time it takes for sound waves to travel from the auxiliary speakers (320, 420) to the user's ears (332a / b, 432a / b) is calculated based on the physical distance and speed of sound from the auxiliary speakers (320, 420) to the user's ears (332a / b), and also based on any wireless delay if the auxiliary speakers (320, 420) are wirelessly connected to the audio system (300, 400). The delay is determined by calculating the difference between the first and second times. If the first time is longer than the second time, the delay is applied to the auxiliary speakers (320, 420); if the second time is longer than the first time, the delay is applied to the front stereo speakers (310, 410). Typically, it can be assumed that the front stereo speakers (310, 410) are approximately 100cm to 140cm from the user's ears (332a / b, 432a / b). The difference in time required for sound waves to reach the user's ears (332a / b, 432a / b) can also be determined by first calculating the difference between the physical distance from the pair of front stereo speakers (310, 410) to the user's ears (332a / b, 432a / b) and the physical distance from the pair of auxiliary speakers (320, 420) to the user's ears (332a / b, 432a / b), then using the speed of sound to calculate the time difference, and finally taking into account wireless latency (if any). In one example, the pair of front stereo speakers (310) is connected to the audio system (300) via a wired connection (350), while the pair of auxiliary speakers (320) is connected to the audio system wirelessly (360) via Bluetooth LE audio in broadcast mode with a latency of 20ms. The distance from the pair of front stereo speakers (310) to the user's ears (332a / b) is 120cm (midpoint between 100cm and 140cm). The distance from the auxiliary loudspeaker (320) to the user's ear (332a / b) is 20cm. The speed of sound is taken as 343 m / s.Calculations show that a physical distance difference of 100cm requires an application of approximately 3ms delay to the pair of auxiliary speakers (320). Considering a wireless delay of 20ms (which requires an application of 20ms delay to the pair of front stereo speakers (310)), in this example, an application of 17ms delay to the pair of front stereo speakers (310) is used.

[0022] A set of pre-calibrated equalization (EQ) settings is stored (or saved) in storage modules (346, 416). This set of pre-calibrated EQ settings is derived from a comparison of the measured binaural level difference (ILD) of the audio system with the universal ILD, and is pre-calibrated to reduce the difference between the measured ILD and the universal ILD.

[0023] Test audio signals are played through the pair of front stereo speakers (310, 410) and the pair of auxiliary speakers (320, 420), and the binaural level difference (ILD) at the user's ear (332a / b, 432a / b) position is measured in the frequency range of 1 kHz to 10 kHz to obtain the measured ILD. For example, a head and torso simulator or binaural microphones can be used to measure the ILD at the user's ear (332a / b, 432a / b) position. The measured ILD is compared with a generic ILD that represents the spatial audio effect of headphones, and a set of equalization (EQ) settings for the pair of auxiliary speakers (320, 420) is derived to reduce the difference between the measured ILD and the generic ILD. The EQ settings are derived by adjusting the EQ settings so that the difference between the measured ILD and the generic ILD in the specified frequency range (e.g., 1 kHz to 10 kHz) does not exceed a predetermined threshold of approximately ±5 dB. A universal ILD can be obtained by directing a pair of reference stereo speakers toward the user's ears (332a / b, 432a / b), playing a test audio signal through these speakers, and measuring the ILD at the user's ear (332a / b, 432a / b) location in the frequency range of 1 kHz to 10 kHz. Alternatively, a universal ILD can be obtained by extracting the ILD from HRTF data from a universal database, such as the CIPIC HRTF database, ARI HRTF database, the Acoustic Spatial Directional Format (SOFA), the MIT KEMAR HRTF database, and the OpenSL HRTF database.

[0024] The audio processing modules (348, 418) are configured to apply the set of pre-calibrated EQ settings stored in the storage modules (346, 416) to the pair of auxiliary speakers (320, 420). By applying delay and equalization (EQ) adjustments, the audio system reproduces the headphone-like sound experience during playback using the pair of front stereo speakers (310, 410) and the pair of auxiliary speakers (320, 420). Advantageously, this audio system requires less computationally intensive processing methods (such as delay and equalization (EQ) adjustments) to achieve a headphone-like sound experience, thus eliminating more complex and computationally intensive processing methods (such as binaural rendering or real-time HRTF processing). By focusing on aligning sound arrival times through simple delay adjustments and optimizing spectral balance through pre-calibrated EQ settings, the system effectively reproduces the binaural cues necessary for spatial audio perception. This streamlined approach minimizes hardware and / or software usage, reduces latency, and ensures compatibility with various morphological factors of the pair of auxiliary speakers while maintaining high-quality audio output. Advantageously, this audio system is designed to work with standard stereo audio sources, without relying on proprietary multi-channel audio formats. This simplifies integration with a wide range of audio devices and content, as stereo is the most commonly used audio format across media platforms. By utilizing delay and equalization adjustments, the system effectively creates a spatial audio experience without the need for complex surround sound encoding or decoding, making it easier to use, more cost-effective, and universally compatible with existing audio sources.

[0025] The innovation of this disclosure lies in applying binaural technology to a speaker system, rather than relying solely on headphone-based designs. The use of binaural technology, combined with a strategically placed rear speaker layout, ensures a superior audio experience by maintaining the integrity of spatial cues and providing an immersive sound field.

[0026] Enhancing Spatial Accuracy in Games: Many game audio designs are optimized for headphone playback. This system's ability to simulate a headphone sound field allows gamers to experience spatially accurate audio, potentially improving gameplay performance.

[0027] Comfort: Unlike headphones, near-ear speakers offer a comfortable listening experience suitable for extended use.

[0028] By meeting the demand for spatially accurate and comfortable audio solutions, this disclosure offers significant advancements in the field of immersive audio systems, particularly for gaming and multimedia applications.

[0029] Therefore, it can be seen that a method and system for reproducing headphone sound using front and auxiliary speakers has been provided to reproduce the advantages of headphones while avoiding their associated discomfort and positioning problems.

[0030] While exemplary embodiments have been presented in the foregoing description of specific implementations of the embodiments of this disclosure, it should be understood that numerous variations exist. It should also be understood that these exemplary embodiments are merely examples and are not intended to limit the scope, applicability, operation, or configuration of this disclosure in any way. Rather, the foregoing detailed embodiments will provide those skilled in the art with a convenient roadmap for implementing the exemplary embodiments of this disclosure, and it should be understood that various changes can be made to the functionality and arrangement of the steps described in the exemplary embodiments and the methods of operation without departing from the scope of this disclosure as set forth in the appended claims.

Claims

1. A method for reproducing headphone sound using a front speaker and an auxiliary speaker in an audio system, the method comprising: A pair of front stereo speakers and a pair of auxiliary speakers are positioned near the user's ears in a predetermined configuration; Apply a delay to the pair of front stereo speakers or the pair of auxiliary speakers; The test audio signal is played through the pair of front stereo speakers and the pair of auxiliary speakers; The interaural level difference (ILD) at the user's ear in the frequency range of approximately 1 kHz to approximately 10 kHz is measured to obtain the measured ILD; The measured ILD is compared with a generic ILD that represents the spatial audio effect of a headphone class; Export a set of equalization (EQ) settings for the pair of auxiliary speakers to reduce the difference between the measured ILD and the general ILD; as well as Store the set of EQ settings for use in the audio system.

2. The method according to claim 1, wherein, ILD measurements at the user's ears are performed using a head and torso simulator or a binaural microphone.

3. The method according to claim 1, wherein, The step of applying a delay to the pair of front stereo speakers or the pair of auxiliary speakers further includes: The test audio signal is played through the pair of front stereo speakers; The first moment the test audio signal reaches the user's ear is measured; The test audio signal is played through the pair of auxiliary speakers; Measure the second time when the test audio signal reaches the user's ear; and The delay is determined by calculating the difference between the first time and the second time. If the first time is longer than the second time, then the delay is applied to the pair of auxiliary speakers, and If the second time is longer than the first time, the delay is applied to the pair of front stereo speakers.

4. The method according to claim 1, wherein, The step of applying a delay to the pair of front stereo speakers or the pair of auxiliary speakers further includes: Calculate the first time when the sound waves reach the user's ear from the pair of front stereo speakers; Calculate the second time when the sound waves reach the user's ear from the pair of auxiliary speakers; The delay is determined by calculating the difference between the first time and the second time, and If the first time is longer than the second time, then the delay is applied to the pair of auxiliary speakers; If the second time is longer than the first time, then the delay is applied to the pair of front stereo speakers. Wherein, if either of the pair of front stereo speakers and the pair of auxiliary speakers is wirelessly connected to the audio system, the first time and the second time include the delay time of the wireless delay.

5. The method according to claim 1, wherein, The pair of front stereo speakers near the user's ears include: the user's ears being approximately 100cm to 140cm away from the pair of front stereo speakers.

6. The method according to claim 1, wherein, The universal ILD is obtained by directing a pair of reference stereo speakers toward the user's ear, playing a test audio signal through the pair of reference stereo speakers, and measuring the ILD of the user's ear in the frequency range of about 1 kHz to about 10 kHz.

7. The method according to claim 1, wherein, The generic ILD is obtained from a generic database.

8. The method according to claim 1, wherein, The pair of auxiliary speakers are near-ear type and are implemented in the form of a group selected from: neckband speakers, neck strap speakers, headband speakers, chair speakers, eyeglass frames, and headwear such as baseball caps, top hats, and beanies.

9. The method according to claim 8, wherein, The low-frequency components of the audio output of the pair of auxiliary speakers are removed.

10. The method according to claim 9, wherein, The low-frequency components of the audio output of the pair of auxiliary speakers are removed by applying a high-pass filter.

11. An audio system for reproducing headphone sound using a pair of front stereo speakers and a pair of auxiliary speakers, the audio system comprising: The pair of front stereo speakers and the pair of auxiliary speakers are configured to be placed near the user's ears; A delay module is configured to apply a delay to the pair of front stereo speakers or the pair of auxiliary speakers; The storage module is configured to store a set of pre-calibrated equalization (EQ) settings; as well as The audio processing module is configured to apply the set of pre-calibrated EQ settings to the pair of auxiliary speakers. The set of pre-calibrated EQ settings is derived from a comparison of the measured binaural level difference (ILD) of the audio system with the general ILD, and is pre-calibrated to reduce the difference between the measured ILD and the general ILD.

12. The audio system according to claim 11, wherein, The delay is obtained by a delay measurement module, which is configured to: The test audio signal is played through the pair of front stereo speakers; The first moment the test audio signal reaches the user's ear is measured; The test audio signal is played through the pair of auxiliary speakers; Measure the second time when the test audio signal reaches the user's ear; The delay is determined by calculating the difference between the first time and the second time; If the first time is longer than the second time, then the delay is applied to the pair of auxiliary speakers; and If the second time is longer than the first time, the delay is applied to the pair of front stereo speakers.

13. The audio system according to claim 11, wherein, The delay is obtained by a delay calculation module, which is configured as follows: Calculate the first time when the sound waves reach the user's ear from the pair of front stereo speakers; Calculate the second time when the sound waves reach the user's ear from the pair of auxiliary speakers; The delay is determined by calculating the difference between the first time and the second time; If the first time is longer than the second time, then the delay is applied to the pair of auxiliary speakers; and If the second time is longer than the first time, then the delay is applied to the pair of front stereo speakers. Wherein, if either of the pair of front stereo speakers and the pair of auxiliary speakers is wirelessly connected to the audio system, the first time and the second time include the delay time of the wireless delay.

14. The audio system according to claim 11, wherein, The user's ear is approximately 100cm to 140cm away from the pair of front stereo speakers.

15. The audio system according to claim 11, wherein, The universal ILD is obtained by directing a pair of reference stereo speakers toward the user's ear, playing a test audio signal through the pair of reference stereo speakers, and measuring the ILD at the user's ear position in the frequency range of about 1 kHz to about 10 kHz.

16. The audio system according to claim 15, wherein, ILD measurements at the user's ear location are performed using a head and torso simulator or a binaural microphone.

17. The audio system according to claim 11, wherein, The generic ILD is obtained from a generic database.

18. The audio system according to claim 11, wherein, The pair of auxiliary speakers are near-ear type and are implemented in the form of a group selected from: neckband speakers, neck strap speakers, headband speakers, chair speakers, eyeglass frames, and headwear such as baseball caps, top hats, and beanies.

19. The audio system according to claim 18, wherein, The low-frequency components of the audio output of the pair of auxiliary speakers are removed.

20. The audio system according to claim 19, wherein, The low-frequency components of the audio output of the pair of auxiliary speakers are removed by applying a high-pass filter.

Images