JP2003199200A - Rear channel speaker system similar to headphones and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provides a control system for sound effect system and a system for earphone-like rear speakers. <P>SOLUTION: This invention provides a headphone-like or earphone-like device with rear speakers, wherein the headphone-like or earphone-like device includes an opening for receiving the front speaker signal. Then the signal is transmitted to the front, rear and sub-woofer signal to associated speakers. The signal to the rear speakers is processed by HRTF and means for creating virtual speakers to obtain virtual speakers of the rear side. The processed signal is transmitted to the rear speaker. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a system for producing digital sound effects, and more particularly,
The present invention relates to a method and system suitable for a home theater system, wherein the system achieves excellent acoustic effect by a rear channel speaker similar to an earphone or a headphone.

[0002]

2. Description of the Related Art With the rapid development of the electronic industry, it is already universal to enjoy acoustic effects including advanced acoustic effects and visual effects in computers. Therefore, the demand for video and audio performance is increasing. In addition to higher demands on resolution and visual quality, multi-channel sound effects have gradually replaced stereo and mono sound effects in the field of audio frequencies and sound effects. Many technologies are evolving forms of multi-channel audio effects to provide a more realistic and more immersive hearing experience in home theaters. The individual audio channels of the multi-channel signal are transmitted to multiple speakers located throughout the home theater to provide creative and inspiring sound effects. As the home entertainment system market expands, other multi-channel audio systems will become available to the general consumer. Humans can locally hear and listen to the left or right side because of the difference in the arrival time and the level of the voice recognized by both ears.

Head-related transfer functions (HRTFs) of the brain part are virtual three-dimensional (3
D) Used to simulate sound and its location. The shape of the human head, the body and the auditory system affect the brain and cause the position of the sound source to be sensed. The HRTF describes the characteristics of the human head, body, and auditory system, and thus the HRTF is the size and shape of the head, the characteristics of the canal of the ear, that is, the size and shape of the ear canal. Affected by. The HRTF is a typical function of frequency and relative orientation between the head and the sound source, and HRTF reveals frequency response and frequency filters and the inherent delay and reflection in the human head. Three-dimensional sound, by adjusting the frequency and delay of the audio signal according to HRTF,
A simulated position can be simulated from a fixed speaker position. United States Patent No. 57
29612 "Methods and apparatus for measuring head related transfer functions"
Clearly discloses a low-cost method that achieves an accurate acoustic transfer function by a head-related transfer function of the brain. The technology was granted a patent on May 17, 1998.

The unique HRTF is obtained by measuring and calculating the characteristics of the head, ears and body in detail for each individual over time. The individual measurements are converted by a suitable processing device into a transfer function that can be used to adjust the audio signal output characteristics of the individual earphones to simulate a three-dimensional sound.

That is, the HRTF simulates the three-dimensional sound effect by the sound heard by the human ear, and the parameters of the three-dimensional sound effect felt at each location in space are the distance, the direction, and the vertical height at which they match. It is decided by the size. Therefore, the listener feels real. HRTF
Use an artificial head, or place a microphone in the human ear to increase the frequency range of individual sound sources to 20H.
It has to be measured as z-20 KHz and the result is a preliminary HRTF library. The preliminary HRTF library goes through a mathematical process to generate the parameters required for a DSP digital filter. 3D position audio can be emulated by the earphones as long as monophonic sound waves are processed by the left and right digital filters.

HRTF applied to personal computer
3D stereophonic audio device of the present invention comprises a simulated multi-surround speaker with two virtual speakers, and five virtual speakers are simulated to surround the space around the listener to obtain the sound effect of a home theater. However, 5.1CH DVD or 4CH 3D games are used to generate virtual speakers on the rear side using HRFT to replace the substantial speakers provided by DVD and 3D games that have some problems. .

Earphones must have the ability to provide good bass. The bass wavelength is longer than the size of the human head, so there is no direct information about the bass in the earphone structure. A bass speaker called a subwoofer speaker is effective for all channels. Unfortunately, however, the bass on the rear signal side is filtered and removed from the rear signal.
Therefore, voice control systems have a great need to overcome the above-mentioned problems.

[0008]

SUMMARY OF THE INVENTION It is therefore an object of the invention to disclose a control system for a sound effect system. Another object of the present invention is to provide a rear speaker similar to an earphone.

[0009]

In view of the above situation, the present inventor has made earnest studies and, as a result, has developed a method for forming an acoustic effect described below. That is, a method of forming an acoustic effect, which includes providing a structure similar to a headphone or earphone with a rear speaker, the structure similar to a headphone or earphone for receiving a signal of a front speaker. The signal is transmitted to the corresponding associated speakers such as front, rear and subwoofer, and the signal transmitted to the rear speaker is delayed due to the distance from the front speaker and the signal is transmitted to the rear speaker. Comprises processing the HRTF and means for forming a virtual speaker and transmitting the processed signal to a device similar to a headphone.

[0010]

DETAILED DESCRIPTION OF THE INVENTION Many of the above-identified features and advantages associated with the present invention will be better understood with reference to the following detailed description, as well as with reference to the accompanying drawings. , Its true value is easily recognized.

FIG. 1 is an explanatory diagram of a sound effect system of a 5.1D home theater according to the present invention. FIG. 2 is an explanatory diagram of a system having a structure similar to the headphones according to the present invention. FIG. 3 is a flowchart of the present invention.

A home theater 5.1D sound system (10) is disclosed in FIG. The system (10) comprises a right front speaker (12), a left front speaker (14), a subwoofer speaker (16), a right rear speaker (18) and a left rear speaker (20). One of the features of the present invention is that the right rear speaker and the left rear speaker are configured by a device or structure similar to an earphone or a headphone. Also, features of the present invention concentrate on the rear speaker and control system. A speaker similar to an earphone is attached to the head by the user to form a virtual rear speaker, rather than being installed at a fixed position. The headphone or earphone-like device should not cover the entire ear to avoid obscuring the sound transmitted from the front and subwoofer speakers. Therefore, an opening is provided to hear the sound from the front speaker. The right rear and left rear speakers are provided on both sides of a device similar to headphones or earphones to form a virtual speaker having a rear sound effect.

As shown in FIG. 2, the front channel signal is input to the right front and left front speakers, the center channel signal is transmitted to the center speaker through a cord for transmission, and the subwoofer channel signal is similarly transmitted to the subwoofer. Input to the speaker.

The bass pass filter (LF) couples the left rear signal and the right rear signal to remove high frequency signals. The low frequency signal passes through the filter and is transmitted to the subwoofer speaker. A means for forming a head-related transfer function (HRTF) is coupled to the right rear and left rear signals to simulate a rear side rear virtual speaker. The HRTF comprises signal delay means and filters.
The means for forming the HRTF can be constructed utilizing hardware or software.

The means for delaying the signal couples the right rear and left rear signals to delay the electrical signal transmitted to the right rear and left rear speakers mounted in a structure similar to earphones or headphones. Let This is because the distance from the right rear and left rear speakers to the ear is closer than the distance to the other speakers. Therefore, the means for generating the virtual speaker in the rear and the means for forming the HRTF are connected so as to set the delay time based on the distance D between the user and the front speaker. The function of the means for generating a virtual speaker can be achieved using hardware or software. In general, the delay time is estimated by the speed of voice (VS) in D / air. The delayed signal processed by the HRTF is input to the volume controller for adjusting the output volume. The HRTF simulates the acoustic model heard by the human ear in a three-dimensional space, and at each position in the three-dimensional space, the parameters matching the three-dimensional acoustic effect are determined by its distance, orientation and altitude. To be done.

The signal is amplified and output by a rear speaker supported by a structure similar to an earphone or a headphone. Since the signal output by the rear speaker is delayed, the ear can simultaneously receive the audio signals transmitted from the rear speaker and the front speaker. The signal transmitted to the rear speaker may be changed to a method of radiating by IR (infrared) or RF (radio frequency). Therefore, a structure similar to an earphone or a headphone requires a receiver for receiving a wireless transmission signal.

FIG. 3 illustrates the procedure according to the present invention. In step 300, the present invention provides a headphone or earphone-like structure with rear speakers. A structure similar to the headphones or earphones has an opening (open) for receiving a signal of a front speaker.
ing) is included. Then, in step 310, the sound effects system transmits the front, rear and subwoofer signals to their respective associated speakers. The signal transmitted to the rear speaker is delayed in step 320 depending on the distance between the user and the front speaker. In step 330, the signal is processed by means of forming a head related transfer function (HRTF). Then
In step 340, the signal is transmitted to a structure similar to headphones to generate a virtual speaker in the rear.

As the person skilled in the art will understand, preferred embodiments of the invention have been mentioned above, but this is not a limitation of the invention. Any modification or similar correction included within the spirit and scope of the present invention is included in the scope of the present invention, and such a range includes all the modifications included in the scope and the most similar structure. Consistent with widespread interpretation. Thus, the preferred embodiment described above is capable of identifying various modifications that are within the spirit and scope of the invention.

[0019]

The present invention provides a structure similar to a headphone or earphone worn by the user on the head. A structure similar to the headphones or earphones includes a rear speaker attached to the structure. The headphone or earphone-like structure also includes an opening for receiving front speaker signals. The present invention provides excellent acoustic effects without losing the rear bass.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a sound effect system of a 5.1D home theater according to the present invention.

FIG. 2 is an explanatory diagram of a system having a structure similar to the headphones provided by the present invention.

FIG. 3 is a flowchart of the present invention.

Claims (7)

[Claims] 1. A headphone or earphone-like device having rear speakers, the headphone or earphone-like device including an opening for receiving a front speaker signal; , The rear and subwoofer signals are respectively transmitted to the corresponding associated speakers; the transmission of the signals to the rear speakers is delayed by a head related transfer function (HRTF) based on the distance between the user and the front speaker. Processing; transmitting the processed signal to the rear speaker to form a sound effect comprising forming a virtual speaker in the rear without losing rear bass. 2. The delay time of the delay signal is determined by a numerical value obtained by dividing the distance between the user and the front speaker by the speed of sound in the air.
The method described in. 3. An earphone comprising a device similar to an earphone or a headphone, and a rear speaker provided in the earphone or a device similar to the headphone worn by a user on the head of the earphone. Or, a device similar to a headphone receives sound from a front speaker and a subwoofer speaker and thus does not cover the entire ear, and the rear speaker is similar to the earphone or the headphone, respectively, to form a rear channel acoustic effect. Means for forming the head related transfer function (HRTF) provided on both sides of the device, the means being coupled to left and right rear signals; for forming a virtual speaker in the rear To the means for forming the head related transfer function, Means for forming a loudspeaker; and said signal processed by said means for forming a head related transfer function (HRTF) is transmitted to the rear speaker of the earphone or a device similar to a headphone. . 4. The acoustic effect system according to claim 3, wherein the means for forming the head related transfer function (HRTF) comprises signal delay means and filter means. 5. The sound effect system according to claim 3, further comprising a radio signal transmission device for transmitting a signal by coupling with a means for forming the head related transfer function. 6. The sound effect system according to claim 5, further comprising a receiving device for receiving a transmitted wireless signal, which is installed in a device similar to the earphone or the headphone. 7. The delay time of the delay signal is determined by a numerical value obtained by dividing the distance between the user and the front speaker by the speed of sound in the air.
The sound effect system described in.