JPH07503112A - speaker system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] speaker system background The present invention relates to a speaker system, and in particular, to a DOLBY speaker system. Regarding the center channel speaker system for PROLOGIC) Homen Attar Ru.

Simply put, the Torpy system is a four-channel system devised in the early 1970s. encodes surround sound based on the 4-2-4 matrix method for It is a stereo system. The four original signals are mixed, and when played back, the original four It will play approximately 4 channels: left, center, right, and surround. A two-channel stereo recording signal is generated which is then decoded. 2 Channel Dorhi 1 To generate a stereo recording signal, either a center channel signal or a mono in-phase signal is is added to the left and right channels. Surround channel signals are treated as non-in-phase signals. is added to the left and right channel signals.

During playback, all left channels and all right channels (L + R) or center channel are added in the decoder to reproduce the left channel and right channel signals, while the left channel and right channel The channel difference (LR) is obtained as a non-in-phase surround channel signal. Logi The steering circuit improves the separation of left, center, right, and salau mower signals. It is used during decoding to increase the The surround channel signal is avoid frontal sound or undesirable positioning of channel speakers. There is a delay of about 20 milliseconds to allow for

Central Chai Le provides most of the dialogue and music for movies and television programs, and It also affects the sound. The central channel is used by viewers who are far away from the center. Audio and other sounds originating from on-screen sources are certainly The purpose is to make it appear as if it is occurring from Therefore, for the central speaker system The requirements for this are mainly related to music and the directionality of music in a stereo system. This is different from that for the channel's speakers.

The center channel speaker is acoustically the same as the left and right speakers in its operating frequency range. Is it necessary to be able to output an output level? This output requirement makes the center channel The loudspeaker system minimizes volume velocity performance and thus minimizes sound radiation area. It is necessary to Besides, the center channel speaker system provides physically placed as close as possible to the TV screen to maintain fusion with the sound image. It is a good place to go. Place a central channel speaker system in a spacious living room The most practical place to do this is either above or below the television set. to this Therefore, a center channel speaker system is required to be compact. follow Therefore, the need for miniaturization, along with the need to minimize the radiating area, This is an important design requirement for a maker system.

Two speakers spaced closely apart and emitting the same signal are located far from the axis. There are problems with the characteristics of At a certain frequency related to the distance between the two sound sources, The acoustic outputs from the two sound sources interfere and cancel each other out, causing problems with the system. A large notch appears in the frequency response of the system. Similar to the comb filter, this “knot” This can induce a significant deterioration in sound quality. away from the axis This cancellation is useful so that listeners who listen to the It is desirable to minimize competitive interference.

Two woofers spaced apart and having the same acoustic radiation The destructive interference caused by There is also a possibility that it may occur in the crossover frequency range. Such a canceling effect It is desirable that sources of interference be minimized.

Summary of the invention Simply put, the central channel used by the Dolby 4-channel sound system. A channel speaker system is provided. The first speaker is located at the front of the cabinet. Installed. second and third speakers having a lower frequency range than the first speaker; The speaker is mounted on the first speaker at an angle of approximately 40 degrees in a rear vertical plane from the first speaker. Installed on the front of the cabinet on one side of the cabinet. This arrangement allows for tight spaces. The canceling phase of the sound emitted from the central channel speakers placed at Killed or minimized.

Brief description of the drawing Figure 1 shows a prior art technique in which the listener suffers from sound cancellation due to destructive interference. The central subican stem is shown.

FIG. 2 illustrates the difference in sound due to destructive interference, in accordance with features of the present invention. The central subican stem is shown to represent being killed or minimized.

Detailed description of the preferred embodiment FIG. 1 is a diagram illustrating a speaker cabinet arrangement according to the prior art. torheap 3 channels for Roloncun stem, namely left, right and center channels. A speaker cabinet is shown; surround speakers are not shown. left and right stereo Any type of stereo speaker can be used as a stereo speaker. , receive standard left and right signals. Structure of left and right stereo sound emitting speakers The composition and operation thereof do not form part of the invention and no further discussion thereof is provided. No explanation will be given.

FIG. 1 shows a set of 5.25 inch trie mounted within a common cabinet 16. shows a prior art central speaker system consisting of speakers 12 and 14; . Speakers 12 and I4 are connected to the low frequency eater 18 between speakers 12 and 14. mounted on. Make sure the speaker emits straight to the front, i.e. With respect to the illustrated prior art system mounted on a common front plane baffle, The speaker radiation produces no combined response of the two speakers 12 and 14. do not have. Only the responses in areas A, B and C are reasonably accurate. To the area and E and the path length between the listener and the two speakers 12 and 14 in these areas. The difference is the deviation of one wavelength or the similar passbands of the two speakers. radiation from both speakers 12 and 14 is attenuated. It has sufficient strength to induce an irradiation effect. Compensation for non-optimized speakers The response of Equation includes a cancellation between the acoustic radiation of speakers 12 and 14. This includes spaces with wide angles where interference may occur.

Next, referring to Figure 2, we can see that the center channel speed suppresses the cancellation effect shown in Figure 1. The location of the power is shown. As shown in FIG. 2, the 5.25-inch speaker 12 of this embodiment and 14 are, for example, 375 degrees in the vertical plane with respect to the speaker 18. It is attached at an angle of about 40 degrees towards the rear. The optimal angle is It will vary depending on the size and frequency range of the mosquito. If this type of installation is at an angle, When a person moves away from the axis of the central speaker 18, the speakers 12 and 1 4 and further away from the other axis of speakers 12 and 14.

Therefore, in the frequency range where cancellation occurs due to otherwise destructive interference, , the output from the off-axis speaker will be lower due to its own cancellation. interference cancellation is reduced and/or minimized.

In this one embodiment, horn speaker 18 is a The acoustic center or the front panel of the loudspeaker (not shown) allows for optimum displacement depending on the It can be installed approximately 4.5cm behind the As a result, the sound of the speaker 18 The acoustic center is located near the acoustic centers of the speakers 12 and 14, but more precisely Not done.

This displacement corresponds to the normal viewing angle of television, i.e. from 0 degrees up to 45 degrees from the axis. tweeter-speaker I8 and woofer-speakers 12 and 14 in the range of The effect of destructive interference is minimized by minimizing the variation in path length between Adjustments will be made to further minimize the impact.

FIG. 2 shows tweeter 1 in the center channel speaker system of this embodiment. 8 at a frequency just below the crossover frequency. The approximate listening range of F-12 and F-14 is shown.

The acoustic outputs of speakers 12 and 14 are substantially on the same level. It is reached in phase and no cancellation occurs. In areas B and C, the acoustics of speakers 12 and 14 -Stick outputs are out of phase with each other. However, speakers 12 and 1 The angle of installation 4 is such that the sound from the far speaker is relative to the near speaker. significantly reduces the level, so even in the presence of large phase differences, the system The net impact is small.

prior art FIG.2 Continuation of front page (72) Inventor: Greenberger, Hull, Peri - United States of America Massachusetts setts state 01747 Hopedill Laurelwood Drive 182 (72) Inventor Lyon, Richard, Harold Massachusetts Massachusetts setts state 02178 Belmont 60 Prentice Lane (72) Inventor Starobin, Bradley, Mark United States Masachu -Sets State 02174 Arlington Buena Bistu Road 22

Claims (3)

[Claims] 1. a first speaker (18) attached to the front of the cabinet; from the first speaker (18) at an angle of approximately 40 degrees in a vertical plane; mounted on the front of said cabinet on one side of said first speaker (18); a second speaker (12, 14) having a lower frequency range than the speaker (18); from the first speaker (18) at an angle of approximately 40 degrees in a vertical plane; attached to the front of said cabinet (10) on the other side of said first a third speaker (12, 14) having a lower frequency range than the speaker (18); The center channel speaker of the Dolby 4-channel sound system. Ka system (10). 2. a first stage having a first cabinet providing left channel audio information; Pica (L) and spaced apart from the first speaker cabinet (L), the right channel audio a second speaker (R) having a second cabinet providing audio information; placed between the first and second speaker cabinets (L, R); a third speaker cabinet (10) providing audio sound channel information; The third speaker cabinet (10) is composed of: A third speaker ( 18) and from the third speaker (18) at an angle of approximately 40 degrees in a vertical plane; - attached to the front of said cabinet (10) on one side of said third a fourth loudspeaker (12, 1) with a lower frequency range than the loudspeaker (18); 4) and the third speaker (18) at an angle of approximately 40 degrees in the vertical plane. mounted on the front of said cabinet (10) on the other side of the third speaker (18). , a fifth speaker (12) having a lower frequency range than the third speaker (18); , 14) for a Dolby sound system (1). 0). 3. a first speaker (18) attached to the front of the cabinet (10); from the first speaker (18) at an angle of approximately 40 degrees in a vertical plane; mounted on the front of said cabinet on one side of said first speaker (18); a second speaker (12, 14) having a lower frequency range than the speaker (18); from the first speaker (18) at an angle of approximately 40 degrees in a vertical plane; attached to the front of said cabinet (10) on the other side of said first a third speaker (12, 14) having a lower frequency range than the speaker (18); A speaker system consisting of.