Soundbar

Abstract

The sound bar has a housing and a plurality of acoustic radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, and a center audio channel, at least one of the acoustic radiators comprising a dipole acoustic radiator configured to emit sound in opposite directions along a primary radiation axis.

Description

[Background technology]

[0001] The present disclosure relates to a sound bar.

[0002] A surround sound audio system can be configured to reproduce left, right, center, surround and height channels. A soundbar can be used for the left, right and center channels, but is not usually useful for the height channel. Summary of the Invention [Means for solving the problem]

[0003] All embodiments and features mentioned below can be combined in any technically possible manner.

[0004] In one aspect, a sound bar includes a housing and a plurality of acoustic radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, and a center audio channel, at least one of the acoustic radiators comprising a dipole acoustic radiator configured to emit sound in opposite directions along a primary radiation axis.

[0005] Some examples include one of the above and / or the following features, or any combination thereof. In one example, the dipole sound radiator is configured to output sound for a height audio channel. In one example, the sound bar includes two separate dipole sound radiators, one of the dipole sound radiators configured to output sound for a left height audio channel and the other of the dipole sound radiators configured to output sound for a right height audio channel. In one example, the dipole sound radiator is configured to output sound for either the left audio channel or the right audio channel. In one example, the sound bar includes two separate dipole sound radiators, one of the dipole sound radiators configured to output sound for the left audio channel and the other of the dipole sound radiators configured to output sound for the right audio channel.

[0006] Some examples include one of the above and / or the following features, or any combination thereof. In some examples, the dipole acoustic radiator comprises an audio driver mounted within an enclosure, a front face of the driver configured to radiate forward sound in a direction away from the enclosure and an opposite rear face of the driver configured to radiate rear sound into the enclosure, the enclosure defining one or more openings configured to allow the rear sound to escape from the enclosure to an external environment. In one example, the openings are configured to allow the rear sound to escape from the enclosure along a majority of the perimeter of the enclosure. In one example, the openings include elongated slots. In one example, the housing defines two opposite ends and a front side and a rear side, the dipole acoustic radiator is disposed at one end of the housing, the enclosure is disposed at the one end and the front and rear sides adjacent the one end, and the enclosure openings are disposed at the one end and the front and rear sides adjacent the one end. In one example, the soundbar comprises two separate dipole acoustic radiators, one disposed at each end of the housing, with enclosures disposed at the ends and on the front and rear sides adjacent each end, with enclosure openings at each end and on the front and rear sides adjacent each end. In one example, the housing defines a height between a bottom surface and a top surface, and the opening comprises an elongated slot extending along a majority of the height of the housing. In one example, the opening occupies at least 20% of the area of ​​the enclosure.

[0007] Some examples include one of the above and / or the following features, or any combination thereof. In some examples, the sound radiation of the dipole sound radiator defines main lobes forward and aft along the main radiation axis. In one example, the sound radiation of the dipole sound radiator further defines a null along an axis transverse to the main radiation axis. In one example, the null exhibits a sound pressure level at least 10 decibels below the sound pressure level of the main lobe at one or more sound frequencies. In one example, the dipole sound radiator is configured to radiate sound in a frequency range of 500 Hertz or greater.

[0008] In another aspect, a sound bar includes a housing and a plurality of acoustic radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, a center audio channel, a left height audio channel, and a right height audio channel, the plurality of acoustic radiators comprising two separate dipole acoustic radiators configured to emit sound in opposite directions along a primary radiation axis, one of the dipole acoustic radiators configured to output sound for the left height audio channel and the other of the dipole acoustic radiators configured to output sound for the right height audio channel. The dipole acoustic radiators define sound radiating main lobes forward and rearward along the primary radiation axis and further define a null laterally relative to the primary radiation axis, the null exhibiting a sound pressure level at least 10 decibels lower than the sound pressure level of the main lobes at one or more sound frequencies.

[0009] Some examples include one of the above and / or the following features, or any combination thereof. In one example, each of the dipole acoustic radiators comprises an audio driver mounted within the enclosure, a front face of the driver configured to radiate forward sound away from the enclosure, and an opposite rear face of the driver configured to radiate rear sound into the enclosure, the enclosure defining one or more openings configured to allow rear sound to escape from the enclosure to the outside environment along a majority of the perimeter of the enclosure. In one example, the housing defines two opposite ends and a front side and a rear side, one of two separate dipole acoustic radiators is disposed at each end of the housing, the enclosure is disposed at the ends and the front and rear sides adjacent the respective ends, and the enclosure openings are at each end and the front and rear sides adjacent the respective ends. In one example, the openings of each enclosure occupy at least 20% of the area of ​​the enclosure. [Brief description of the drawings]

[0010] [Figure 1]FIG. 1 is a schematic diagram of a sound bar. [Diagram 2] FIG. 1 is a schematic block diagram of a surround sound system. [Diagram 3] FIG. 1 is a schematic diagram of a dipole acoustic radiator. [Figure 4] 1 is a schematic diagram of a dipole acoustic radiator including an enclosure. [Diagram 5] FIG. 1 is a perspective view of an end of a housing for a sound bar including a height channel transducer. [Figure 6] 1 is a polar plot of the output of a dipole acoustic radiator for a soundbar. [Figure 7] 1 is a plot of sound pressure levels at two angular positions relative to a dipole sound radiator on a soundbar. [Figure 8] 1 is a plot of sound pressure levels at two angular positions relative to a dipole sound radiator on a soundbar. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A soundbar is used to reproduce at least the left, right and center channels of surround sound audio. The surround quality is improved if the listener can perceive the difference in pitch. The height channels are usually reproduced using ceiling mounted speakers. The surround sound system can be simplified if the height channels can be reproduced by the soundbar.

[0012] To perceive the difference in pitch produced by a soundbar, the sound needs to be reflected off the ceiling. Soundbar loudspeakers can be pointed upwards to bounce the sound off the ceiling. However, because loudspeakers are typically omnidirectional, the sound also reaches the listener directly, reducing the height effect.

[0013] The soundbar includes one or more dipole acoustic radiators. Dipole acoustic radiators generate greater sound pressure along their major axis than in an orthogonal direction. In a polar plot of sound pressure or sound energy taken radially around a dipole acoustic radiator, the highest sound pressures are in two main lobes extending in opposite directions along the major axis, and sound pressures are lower in side lobes, sometimes called "nulls", extending in opposite directions along an axis orthogonal to the major axis. In some examples, one or both nulls of a dipole acoustic radiator exhibit sound pressure levels at least 10 decibels lower than the sound pressure levels of one or both main lobes at at least one or more frequencies of the radiated sound.

[0014] When a dipole acoustic radiator is used to reproduce the height channel in a soundbar, the main axis can be pointed up at the ceiling. This arrangement directs the null to the front of the soundbar, towards the listener. Thus, substantially more sound pressure is reflected from the ceiling than reaches the listener directly. As a result, the height channel is reproduced with less influence from the height sounds reaching the listener directly, thus increasing the height effect.

[0015] In some examples, a dipole sound radiator can additionally or alternatively be used to reproduce a left channel and / or a right channel, with the null aimed at the listening position and the main lobe aimed to the left or right, where it can be reflected off the side walls of the room in which the sound bar is located. As with the height channel, this use of a dipole sound radiator in a left / right channel reduces the amount of left or right sound that reaches the listener directly, compared to the reflected sound coming from the left or right. As a result, the left and right channels are reproduced with less influence of left and right sounds reaching the listener directly, resulting in a greater left and right separation effect.

[0016] A dipole sound radiator can be achieved in a number of ways. In one example, a dipole sound radiator includes a sound radiator with the front and back sides substantially open to the environment, such that the sound pressure level (SPL) is approximately the same along the main axis of the front and back of the sound radiator diaphragm at least at some frequencies, but lower on the null axis. The degree to which the front and back sides are open is relative. An effective aperture for dipole-like operation includes an aperture (and any other aspect of the dipole sound radiator that contributes to the front and back sound pressure, such as the design of the acoustic cavity) such that the sound pressure of the sound radiation is greater along the main axis than along the transverse axis, including but not limited to the orthogonal axis. Sound pressure that is the same in both directions along the main axis is also relative. A true theoretical dipole sound radiator has a figure-8 shaped sound pressure polar plot, with equal main lobes forward and backward along the main axis, and zero sound pressure nulls at +90 degrees and -90 degrees from the forward direction (i.e., along the axis orthogonal to the main axis).

[0017] In the soundbar of the present invention, the dipole acoustic radiators have a higher sound pressure along the major axis than along the transverse or orthogonal axis. In most, but not all, cases, the sound pressure along the major axis is at least 10 decibels greater than the sound pressure along or close to the orthogonal axis at some, most, or all of the radiated frequencies. This configuration provides sufficient sound pressure that is directed up (for the height channel) or to the left or right (for the left or right channel) to achieve a height, left, or right channel where the listener perceives the sound as coming from above, left, or right, respectively, while minimizing the amount of sound that is projected directly toward a listener located in front of the soundbar, which would adversely affect the perception of height or direction.

[0018] In another example of a dipole acoustic radiator, two acoustic radiators can be mounted back to back so that they radiate in opposite directions. The radiators can be controlled to radiate in synchrony. Other designs of dipole acoustic radiators are known in the art and are within the scope of this disclosure.

[0019] FIG. 1 is a schematic diagram of a soundbar 10. Soundbar 10 includes a housing 12 having a top 14, a bottom 16, a left end 18, and a right end 20. A soundbar may have any number of sound radiators, but is generally configured to reproduce at least left, center, and right sound channels, as is well known in the art. The present soundbar 10 is also configured to reproduce left and right height audio channels. Although any particular channel may be reproduced using a combination of two or more transducers, the sound radiators of soundbar 10 are functionally represented with numbered blocks representing one or more radiators used to reproduce any particular channel. The radiators include a radiator reproducing the left height channel 28 (radiating primarily upward as shown by arrow 29), a radiator reproducing the right height channel 30 (radiating primarily upward as shown by arrow 31), a radiator reproducing the left channel 24 (radiating primarily to the left as shown by arrow 25), a radiator reproducing the right channel 26 (radiating primarily to the right as shown by arrow 27), and a radiator reproducing the center channel 22 (radiating primarily forward as shown by arrow 23). In some examples, one or more of the left channel, right channel, and center channel are reproduced using an array of multiple radiating elements with controllable delays between elements so that dense polar patterns oriented in the desired direction can be generated. In some examples, any one or more of the left height channel, right height channel, left channel, and right channel can be reproduced using a dipole acoustic radiator.

[0020] FIG. 2 is a functional block diagram of a surround sound system 40 showing one non-limiting use of a sound bar. It should be noted that many surround sound systems do not have all of the channels depicted in the drawing. A processor 42 is configured to receive an input audio signal (wired or wireless) from an audio source 44. The processor 42 provides audio data or signals to audio transducers of a sound bar 46 and any additional transducers not included in the sound bar. The sound bar 46 includes transducers used to reproduce one or more of a center channel 50, a left channel 52, a right channel 54, a left front height channel 55, and a right front height channel 56, respectively. Other channels can include zero or more subwoofers 66, a left surround 58 and a right surround 60, and a left rear height 62 and a right rear height 64, respectively. In some examples such as that shown in FIG. 1, the height channels are not split into front and rear, and each side (left height and right height) is processed using a single channel. It should also be noted that a surround sound system may have additional or different channels, and / or additional or different transducers.

[0021] FIG. 3 is a schematic diagram of a dipole acoustic radiator 80 comprising an audio transducer 82 having a radiating surface (e.g., diaphragm) 84. The transducer 82 is mounted on a panel or other support 86 with openings on the front and rear sides. When the diaphragm 84 is moved up and down, it creates a sound pressure that moves outward along front and rear primary radiation axes 90 and 91, which are ideally parallel. In an ideal radiator, the sound pressures on the front and rear sides are the same and out of phase. Thus, sounds along the two axes perpendicular to the axes 90 and 91 (not shown) cancel each other, creating a null at about 90 degrees to the primary axis. As is known in the art, a polar plot of a dipole acoustic radiator looks like a figure eight aligned along the primary axis. In some examples, the dipole acoustic radiator is configured such that the primary radiation axis is directed in a desired direction or at a desired location and / or the null is directed in a desired direction or at a desired location. In the example of a dipole acoustic radiator used for a soundbar height channel, the primary radiation axis is directed upwards towards the ceiling and the null is directed outwards towards the expected location of the listener (e.g. directly in front of a soundbar intended to be mounted under or above a television). In this example, the sound will hit the ceiling and be reflected from the ceiling and thus be perceived as emanating from above the listener, while the null directed towards the listener helps to maintain the perception of height. In the example of a dipole acoustic radiator used for a soundbar left channel or a soundbar right channel, the primary radiation axis is directed left or right towards the side wall of the room and the null is directed outwards towards the expected location of the listener (e.g. directly in front of a soundbar intended to be mounted under or above a television). In this example, the sound will hit the left or right wall and be reflected from it and thus be perceived as emanating from the left or right of the listener, while the null directed towards the listener helps to maintain the left or right perception. In some examples, a dipole acoustic radiator 80 is used as the transducer for the left height channel, the right height channel, the left channel, and / or the right channel of the soundbar.

[0022] FIG. 4 is a schematic diagram of a dipole sound radiator 92 that can be used in a sound bar. The dipole sound radiator 92 includes a transducer 95 mounted within an enclosure 93. The enclosure 93 includes a top 94 with an opening 96 for emitting front radiation. One or more sides and / or a bottom of the enclosure 93 are sufficiently open so that sound also radiates from the rear of the transducer. The area and location of the opening from the rear of the transducer to the environment will determine, in part, how close the dipole sound radiator radiation pattern is to the ideal and the frequencies at which dipole behavior is exhibited. The size, shape, and location of the rear opening can be selected to achieve the desired dipole performance, taking into account any constraints imposed by the physical design of the sound bar in which the dipole sound radiator 92 is located.

[0023] FIG. 5 is a perspective view of a portion of a left end 100 of a housing for a soundbar including a height channel transducer, in this example a left height channel dipole sound radiator (not shown). The end enclosure 110 includes an oval opening 114 at the top 112 configured to hold an oval sound transducer (not shown) used to generate sound for the dipole sound radiator. The oval shape is exemplary and not limiting to the scope of the present disclosure, and the shape of the transducer may be circular, rectangular, or other shapes. In a soundbar in which both the left and right height channels are reproduced using two separate dipole sound radiators, the right end of the housing (not shown) may be identical to the left end and carry a single dipole transducer for the right height channel.

[0024] The enclosure 110 is further defined by an end wall 118, a front wall 116, and a rear wall 120. In one example, each of these three walls includes one or more openings that allow sound pressure to escape from the rear of the transducer to the environment. The openings may be circular, elliptical, or any shape. In the examples herein, the openings occupy 0-100% of the area of ​​the wall. Both the front and rear sides of the transducer are open to the environment, so that the transducer functions as a dipole sound radiator. The bottom wall 104 does not include an opening, because in most cases the sound bar will be located on a surface that will block such an opening. The lower portion, however, may include an opening. Any one or more of the sides and lower portions of the enclosure 110 may have a desired open area, which may be achieved by a completely open side, or one or more openings of any desired size, shape, and location. In one example, the openings are elongated slots that extend along most of the height of each of the three sides. In one example, the opening extends along most of the perimeter of the enclosure, and in some examples, the opening occupies at least about 20% of the area of ​​the enclosure behind the transducer diaphragm to achieve sufficient dipole behavior to reproduce the height channel.

[0025] Also shown is a small portion 102 of the remainder of the soundbar housing, including a portion of an opening 130 configured to accommodate a left channel transducer(s) (not shown). The locations of other transducers in the soundbar, such as the transducer(s) for the center and right channels, and the right height channel, are not shown. In some examples, the soundbar includes a left height channel and a right height channel. In one example, one dipole acoustic radiator is used to reproduce the right height channel and another dipole acoustic radiator is used to reproduce the left height channel.

[0026] FIG. 6 is a polar plot 150 of the output of a dipole sound radiator for a sound bar. The plot 150 includes sound pressure (in decibels) at 360 degrees around the transducer. The 0 degree direction is on axis for forward radiation and the 180 degree direction is on axis for rear radiation. The 90 and 270 degree radiations are on an axis (called the null axis) perpendicular to the front and rear primary axes. As shown, at 250 and 501 hertz the plot is essentially a pure dipole, with essentially equal sound pressures at 0 and 180 degrees, and approximately 13 decibels lower sound pressures at 90 and 270 degrees. At 1000 hertz a transition begins to occur and the side nulls weaken to approximately 8 decibels. Above that frequency, the radiator becomes more unipolar (upwards firing), but the side energy is naturally lower, so the objective of the dipole radiator (greater sound pressure directed upwards at the ceiling than directly towards the listener) is still met. When the front axis is pointed up at the ceiling and the null is pointed directly in front of the soundbar, a listener positioned in front of the soundbar will perceive the sound as emanating from the ceiling. Thus, dipole acoustic radiators can reproduce height channels.

[0027] FIG. 7 is a plot of sound pressure levels over a wide frequency range (100 Hertz to approximately 20 kilohertz) at two angular positions for a dipole acoustic radiator that may be used in a soundbar similar to that shown in FIG. 5. Plot line 172 is along the front major axis (i.e., 0 degrees on the polar plot) and plot line 174 is at 90 degrees. The peak just above 1000 Hertz is due to a Helmholtz resonance caused by the internal volume of the rear enclosure combined with the area of ​​the opening to the environment. As shown, the null axis radiation is less than the radiation along the major axis across the entire spectrum, and at many frequencies the difference is more than 5 decibels. FIG. 8 is a similar plot of sound pressure levels at 20 degrees (line 182) and 90 degrees (line 184) for the same transducer design. The separation is even greater at these angular positions. In some examples of left or right height channel designs, understanding the sound pressure at 20 degrees and 90 degrees can be useful to understand which sounds are more likely to reach the listener by reflecting off the ceiling (20 degree sounds) and which sounds are more likely to reach the listener directly (90 degree sounds). The plots in Figures 7 and 8 support dipole-like outputs at two angular positions separated by 70 and 90 degrees for a dipole acoustic radiator for a soundbar across the illustrated frequency range.

[0028] In some examples, the dipole is oriented to maintain the maximum difference between the energy directed upwards towards the ceiling and the energy directed towards the listener. In such examples, the directivity curve of the dipole has an upward beam and a downward beam, and a null that is three-dimensional in the horizontal plane. The null recess is very narrow and deep, while the upward lobe is wide and changes more gradually with angle. If the dipole were tilted slightly forward instead of pointed straight up, the energy reflected from the ceiling could be slightly greater (about 1 decibel), but the deepest null would not be directed towards the user (in the horizontal plane), thereby reducing the benefit of the dipole configuration. The tilt around the null is much greater than the tilt of the upward lobe, so the maximum difference between the two angles is achieved when the null is in the horizontal plane. Thus, the maximum difference is generally achieved when the major axis is pointing straight up, rather than at an angle of, say, 20 degrees from the vertical. However, in some implementations, the dipole driver(s) can be angled 1-30 degrees toward or away from the user, e.g., 20 degrees toward the user, and even in those angled implementations, the dipole configuration can help improve the directionality of the audio output. The dipole's main axis can also be angled slightly to the left or right (e.g., tilting the dipole driver toward or away from the center of the soundbar). An outward-facing dipole can, for example, increase the apparent width of the two height channels. In such a configuration, the dipole driver(s) can be angled 1-30 degrees inward or outward, e.g., 20 degrees outward, depending on the desired configuration.

[0029] Dipole drivers are beneficial when used to render audio that is intended to be spatialized. For example, the use of one or more dipole drivers can provide a better sense of audio height and / or diffusion by improving the audio output directivity, thereby improving the output of audio that includes a height component, such as Dolby Atmos® audio content or other object-oriented audio content.

[0030] Especially in the far field, dipole behavior can result in low frequency cancellation, thus resulting in an extra approximately 6 decibels per octave roll-off that must be equalized. Thus, there is a practical limit to how low a frequency can be driven at a dipole transducer, based on the size of the driver and its excursion capabilities. 500 Hertz is roughly a practical lower limit for dipole acoustic radiators, in part because at lower frequencies the perception of height is reduced and therefore the benefit of going below about 500 Hertz is less. In some instances, dipole acoustic radiators are ideally configured to reproduce sounds at frequencies where dipole radiation causes a 10-15 decibel loss in low frequency output from the highest frequency down to about 500 Hertz or lower.

[0031] Sound pressure measurements of dipole acoustic radiators can assist in soundbar design, driver(s) placement and orientation, and driver enclosure design considerations (e.g., rear enclosure volume and rear opening area). Sound pressure measurements and polar plots are information that can be used to achieve a good soundbar and surround sound design compromise. Sound pressure measurements provide information about frequency response. Sound pressure measurements can also be used to determine whether a design achieves good spacing between curves (10-15 decibels), uniformity of spacing across the frequency range, and proper frequency response (relatively smooth and not rolled off at low frequencies where excessive boosting may be required).

[0032] Elements of the figures are shown and described as individual elements in block diagrams. These elements may be implemented as one or more of analog or digital circuits. Alternatively, or additionally, these elements may be implemented by one or more microprocessors executing software instructions. The software instructions may include digital signal processing instructions. Operations may be performed by analog circuitry or by a microprocessor executing software that performs the equivalent of an analog operation. Signal lines may be implemented as separate analog or digital signal lines, as separate digital signal lines with appropriate signal processing capable of processing the separate signals, and / or as elements of a wireless communication system.

[0033] When a process is depicted or suggested in a block diagram, the steps may be performed by one element or by multiple elements. The steps may be performed collectively or at different times. The elements performing the activities may be physically the same or in close proximity to each other, or may be physically separate. An element may perform more activities than one block. The audio signal may be coded or uncoded and may be transmitted in either digital or analog form. Conventional audio signal processing equipment and operations may be omitted from the drawings.

[0034] Although multiple implementations have been described, it is understood that additional modifications can be made without departing from the scope of the inventive concepts described herein, and therefore, other examples are within the scope of the following claims. [Explanation of symbols]

[0035] 10. Soundbar 12. Housing 14 Upper part 16 Lower 18 Left end 20 Right end 22 Center Channel 24 Left Channel 26 Right Channel 28 Left Height Channel 30 Right Height Channel 40 Surround Sound System 42 Processor 44 Audio Sources 46 Soundbar 50 Center Channel 52 Left Channel 54 Right Channel 55 Left front height channel 56 Right front height channel 58 Left Surround 60 Right Surround 62 Left rear height 64 Right rear height 66 Subwoofer 80 Dipole Acoustic Radiator 82 Audio Transducer 84 Radiation surface (vibration plate) 86 Panel (support) 90, 91 Posterior primary radial axis 92 Dipole Acoustic Radiator 93 Enclosure 94 Top 95 Transducer 96 Opening 100 Left end of housing 102 Small portion 104 Bottom wall 110 End Enclosure 112 Top 114 Oval Opening 116 Front wall 118 End Wall 120 Back wall 130 Opening 150 Polar plot of the output of a dipole acoustic radiator

Claims

1. A sound bar, Housing and a plurality of acoustic radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, and a center audio channel, at least one of the acoustic radiators comprising a dipole acoustic radiator configured to emit sound for a height audio channel in an opposite direction along a primary radiation axis.

2. The soundbar of claim 1, wherein the dipole acoustic radiator comprises two separate dipole acoustic radiators, one of the dipole acoustic radiators configured to output sound for a left height audio channel and the other of the dipole acoustic radiators configured to output sound for a right height audio channel.

3. The soundbar of claim 1, wherein the dipole acoustic radiator comprises two separate dipole acoustic radiators, one of the dipole acoustic radiators configured to output sound for the left audio channel and the other of the dipole acoustic radiators configured to output sound for the right audio channel.

4. A sound bar, Housing and a plurality of acoustic radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, and a center audio channel, at least one of the acoustic radiators comprising a dipole acoustic radiator configured to radiate sound in opposite directions along a primary radiation axis; 11. The soundbar, wherein the dipole acoustic radiator comprises an audio driver mounted within an enclosure, a first face of the driver oriented in a direction in which sound is emitted along one of the primary radiation axes configured to radiate forward sound away from the enclosure, and a second face of the driver oriented in a direction in which sound is emitted along an opposite other of the primary radiation axes configured to radiate rear sound into the enclosure, the enclosure defining one or more openings configured to allow the rear sound to escape from the enclosure to an external environment.

5. 5. The soundbar of claim 4, wherein the openings are configured to allow the rear sound to escape the enclosure along a portion of a perimeter of the enclosure.

6. The soundbar of claim 4 , wherein the opening comprises an elongated slot.

7. 5. The soundbar of claim 4, wherein the housing defines two opposing ends and a front side and a rear side, the dipole acoustic radiator is disposed at one end of the housing, the enclosure is disposed at the one end and at the front and rear sides adjacent the one end, and the enclosure openings are disposed at the one end and at the front and rear sides adjacent the one end.

8. 8. The soundbar of claim 7 comprising two separate dipole acoustic radiators, one located at each end of the housing, the enclosure located at the ends and at the front and rear sides adjacent the respective ends, and the enclosure openings at the respective ends and at the front and rear sides adjacent the respective ends.

9. 8. The soundbar of claim 7, wherein the housing defines a height between a lower portion and an upper portion, and the opening comprises an elongated slot extending along a portion of the height of the housing.

10. 5. The soundbar of claim 4, wherein the opening occupies at least 20% of an area of ​​the enclosure.

11. A sound bar, comprising: Housing and a plurality of acoustic radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, and a center audio channel, at least one of the acoustic radiators comprising a dipole acoustic radiator configured to radiate sound in opposite directions along a primary radiation axis; A sound bar, wherein the sound radiation of said dipole acoustic radiators defines main lobes forward and rearward along said main radiation axis.

12. 12. The soundbar of claim 11, wherein the sound radiation of the dipole acoustic radiator further defines a null along an axis transverse to the main radiation axis.

13. 13. The soundbar of claim 12, wherein the nulls exhibit sound pressure levels at least 10 decibels below the sound pressure level of the main lobe at one or more audio frequencies.

14. 12. The soundbar of claim 1, 4 or 11, wherein the dipole acoustic radiator is configured to radiate sound in a frequency range of 500 Hertz and above.

15. A sound bar, Housing and a plurality of sound radiators carried by the housing and configured to output sound for at least a left audio channel, a right audio channel, a center audio channel, a left height audio channel, and a right height audio channel, the plurality of sound radiators comprising two separate dipole sound radiators configured to emit sound in opposite directions along a main radiation axis, one of the dipole sound radiators configured to output sound for the left height audio channel and the other of the dipole sound radiators configured to output sound for the right height audio channel; 11. The soundbar, wherein the dipole acoustic radiator defines sound radiating main lobes forward and rearward along the main radiation axis and further defines a null transversely to the main radiation axis, the null exhibiting a sound pressure level at least 10 decibels below the sound pressure level of the main lobe at one or more sound frequencies.

16. 16. The soundbar of claim 15, wherein each of the dipole acoustic radiators comprises an audio driver mounted within an enclosure, a first face of the driver oriented in a direction in which sound is emitted along one of the primary radiation axes configured to radiate forward sound away from the enclosure, and a second face of the driver oriented in a direction in which sound is emitted along an opposite other of the primary radiation axes configured to radiate rear sound into the enclosure, the enclosure defining one or more openings configured to allow the rear sound to escape from the enclosure to an external environment along a portion of a perimeter of the enclosure.

17. 17. The soundbar of claim 16, wherein the housing defines two opposing ends and a front and a rear side, one of the two separate dipole acoustic radiators is disposed at each end of the housing, the enclosure is disposed at the ends and at the front and rear sides adjacent the respective ends, and the enclosure openings are at the respective ends and at the front and rear sides adjacent the respective ends.

18. 20. The soundbar of claim 17, wherein the opening in each enclosure occupies at least 20% of the area of ​​the enclosure.

Images