Soundbar

Abstract

A soundbar 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, wherein at least one of the acoustic radiators comprises a dipole acoustic radiator configured to emit sound in opposite directions along a primary radiation axis.

Description

Background Technology

[0001] This disclosure relates to soundbars.

[0002] Surround sound audio systems can be configured to reproduce the left, right, center, surround, and height channels. Soundbars can be used for the left, right, and center channels, but are generally not suitable for the height channel. Summary of the Invention

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

[0004] In one aspect, a soundbar 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, wherein at least one of the acoustic radiators includes a dipole acoustic radiator configured to emit sound in opposite directions along a main radiation axis.

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

[0006] Some examples may include one or any combination of the features described above and / or below. In some examples, the dipole acoustic radiator includes an audio driver mounted in a housing such that a front surface of the driver is configured to radiate forward sound away from the housing, and an opposing rear surface of the driver is configured to radiate backward sound into the housing, and the housing defines one or more openings configured to allow the backward sound to escape from the housing into the external environment. In one example, the opening is configured to allow the backward sound to escape from the housing along a substantial portion of its periphery. In one example, the opening includes an elongated slot. In one example, the housing defines two opposing ends and a front and a rear side, and the dipole acoustic radiator is located at one end of the housing such that the housing is located at that end and the front and rear sides adjacent to that end, and the housing opening is located at that end and the front and rear sides adjacent to that end. In one example, the soundbar includes two separate dipole radiators, one dipole radiator located at each end of the housing, such that their housings are located at that end and the front and rear sides adjacent to the respective ends, and the housing openings are located at the respective ends and the front and rear sides adjacent to the respective ends. In one example, the housing defines a height between a bottom side and a top side, and the opening includes an elongated slot extending along a substantial portion of the height of the housing. In one example, the opening covers at least 20% of the area of ​​the housing.

[0007] Some examples may include one or any combination of the features described above and / or below. In some examples, the sound emission of the dipole acoustic radiator defines a main lobe extending forward and backward along the main radiation axis. In one example, the sound emission of the dipole acoustic radiator further defines a void along an axis transverse to the main radiation axis. In one example, the void exhibits a sound pressure level at one or more sound frequencies that is at least 10 dB lower than the sound pressure level of the main lobe. In one example, the dipole acoustic radiator is configured to radiate sound in a frequency range of 500 Hz and above.

[0008] In another aspect, a soundbar 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 high audio channel, and a right high audio channel. The plurality of acoustic radiators includes two separate dipole acoustic radiators configured to emit sound in opposite directions along a main radiation axis. One of the dipole acoustic radiators is configured to output sound for the left high audio channel, and the other dipole acoustic radiator is configured to output sound for the right high audio channel. The dipole acoustic radiator defines a sound emission main lobe extending forward and backward along its main radiation axis, and also defines a void transverse to its main radiation axis, wherein the void exhibits a sound pressure level at one or more sound frequencies that is at least 10 dB lower than the sound pressure level of the main lobe.

[0009] Some examples may include one or any combination of the features described above and / or below. In one example, each of the dipole acoustic radiators includes an audio driver mounted in a housing, such that the front surface of the driver is configured to radiate forward sound away from the housing, and the opposite rear surface of the driver is configured to radiate backward sound into the housing, and the housing defines one or more openings configured to allow the backward sound to escape from the housing into the external environment along a substantial portion of the housing's periphery. In one example, the housing defines two opposite ends and front and rear sides, and one of the two individual dipole acoustic radiators is located at each end of the housing, such that their housings are located at that end and the front and rear sides adjacent to the respective end, and the housing openings are located at the respective end and the front and rear sides adjacent to the respective end. In one example, the opening of each housing covers at least 20% of the area of ​​the housing. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of a soundbar.

[0011] Figure 2 This is a functional block diagram of a surround sound system.

[0012] Figure 3 This is a schematic diagram of a dipole acoustic radiator.

[0013] Figure 4 This is a schematic diagram of a dipole acoustic radiator including its housing.

[0014] Figure 5 This is a perspective view of the end of the casing of a soundbar including the height channel transducer.

[0015] Figure 6 This is a polar coordinate graph of the output of the dipole acoustic radiator of the soundbar.

[0016] Figure 7 It is a graph showing the sound pressure levels at two corner positions relative to the dipole radiator of the soundbar.

[0017] Figure 8 It is a graph showing the sound pressure levels at two corner positions relative to the dipole radiator of the soundbar. Detailed Implementation

[0018] A soundbar is used to reproduce at least the left, right, and center channels of surround sound audio. Surround sound quality is improved if the listener can perceive differences in height within the sound. Height channels are typically reproduced by speakers mounted in the ceiling. If height channels can be reproduced by a soundbar, the surround sound system can be simplified.

[0019] To perceive height differences in the sound produced by a soundbar, sound needs to bounce off the ceiling. Soundbar speakers can be pointed upwards to bounce sound off the ceiling. However, because speakers are typically omnidirectional, the sound will also reach the listener directly, reducing the height effect.

[0020] The soundbar of this invention includes one or more dipole acoustic radiators. The dipole acoustic radiator produces a greater sound pressure level along its principal axis than it produces in orthogonal directions. In a polar coordinate diagram of the sound pressure or acoustic energy acquired radially around the dipole acoustic radiator, the highest sound pressure level is found in the two main lobes extending in opposite directions along the principal axis, while the sound pressure level is lower in the side lobes (sometimes referred to as "nulls") extending in opposite directions along axes orthogonal to the principal axis. In some examples, at least at one or more frequencies of the radiated sound, one or both nulls of the dipole acoustic radiator exhibit a sound pressure level at least 10 dB lower than that of one or both main lobes.

[0021] When a dipole radiator is used to reproduce the height channel in a soundbar, the spindle can be pointed upwards, towards the ceiling. This placement directs the sound into the front of the soundbar, towards the listener. Therefore, the sound pressure reflected from the ceiling is much greater than the sound pressure that will reach the listener directly. As a result, the height channel is reproduced, while the effect of the height sound reaching the listener directly is smaller, thus increasing the height effect.

[0022] In some examples, the dipole radiator can also, or alternatively, be used to reproduce the left and / or right channels, where the void points towards the listening position and the main lobe points to the left or right, where it can be reflected from the side walls of the room where the soundbar is located. Similar to the height channel, this use of the left / right channel of the dipole radiator reduces the amount of left or right sound directly reaching the listener compared to reflected sound from the left or right. The result is that the left and / or right channels are reproduced, while the direct impact of sound from the left or right on the listener is smaller, thus increasing the left / right separation effect.

[0023] Dipole acoustic radiators can be implemented in various ways. In one example, a dipole acoustic radiator comprises an acoustic radiator whose front and rear sections are substantially open to the environment, such that the sound pressure level (SPL) is approximately the same along the principal axis of the radiator's diaphragm at least at some frequencies, while the SPL is lower on the virtual axis. The degree of front and rear opening is relative. An effective opening for dipole-like operation involves an opening (and any other aspect of the dipole acoustic radiator that contributes to the front and rear SPL, such as the design of the acoustic cavity) such that the SPL of the acoustic radiation is larger along the principal axis than it is along the transverse axis (including, but not limited to, the orthogonal axis). The fact that the SPL is the same in both directions along the principal axis is also relative. A real theoretical dipole acoustic radiator would have a figure-eight SPL polar diagram with principal lobes equal in the forward and backward directions along the principal axis, and zero SPL virtual lobes at +90 degrees and -90 degrees to the forward direction (i.e., along the axis orthogonal to the principal axis).

[0024] In the soundbar of this invention, the dipole radiator will have a higher SPL along the main axis than along the transverse or orthogonal axis. In most, but not all, cases, at some, most, or all radiation frequencies, the SPL along the main axis is at least 10 dB greater than the SPL along orthogonal or near-orthogonal axis. This arrangement provides sufficient upward-pointing (for the height channel) or left- or right-pointing (for the left or right channel) SPL to achieve the height, left, or right channel, where the listener perceives sound as coming from above, left, or right, respectively, while minimizing the amount of sound projected directly toward a listener located in front of the soundbar, which would negatively affect the perception of height or direction.

[0025] In another example of a dipole acoustic radiator, two radiators can be mounted back-to-back so that they radiate in opposite directions. The radiators can be controlled to radiate synchronously. Other designs of dipole acoustic radiators are known in the art and are included within the scope of this disclosure.

[0026] Figure 1This is a schematic diagram of a soundbar 10. The soundbar 10 includes a housing 12 having a top 14, a bottom 16, a left end 18, and a right end 20. The soundbar may have any number of sound radiators, but is typically configured to reproduce at least the left, center, and right channels, as is well known in the art. The soundbar 10 of the present invention is also configured to reproduce the left height audio channel and the right height audio channel. While any particular channel may be reproduced by a combination of more than one transducer, the sound radiators of the soundbar 10 are functionally indicated by numbered boxes, which indicate one or more radiators used to reproduce any particular channel. The radiators include a radiator that reproduces the left high-frequency channel 28 (and radiates primarily upwards as shown by arrow 29), a radiator that reproduces the right high-frequency channel 30 (and radiates primarily upwards as shown by arrow 31), a radiator that reproduces the left channel 24 (and radiates primarily to the left as shown by arrow 25), a radiator that reproduces the right channel 26 (and radiates primarily to the right as shown by arrow 27), and a radiator that reproduces the center channel 22 (and radiates primarily in the forward direction as shown by arrow 23). In some examples, an array of multiple radiating elements is used to reproduce one or more of the left, right, and center channels with controllable delays between the elements, such that a tightly aligned polar coordinate pattern can be generated. In some examples, a dipole radiator can be used to reproduce any one or more of the left high-frequency channel, right high-frequency channel, left channel, and right channel.

[0027] Figure 2 This is a functional block diagram of a surround sound system 40, illustrating a non-limiting use of a soundbar. It should be noted that many surround sound systems will not have all the channels shown in the figures. Processor 42 is configured to receive input audio signals (via wired or wireless means) from audio source 44. Processor 42 provides audio data or audio signals to the audio transducers of soundbar 46 and any additional transducers not included in the soundbar. Soundbar 46 includes transducers for reproducing one or more of the center channel 50, left channel 52, right channel 54, left front height channel 55, and right front height channel 56, respectively. Other channels may include zero or more of the subwoofer channel 66, left surround channel 58 and right surround channel 60, and left rear height channel 62 and right rear height channel 64. In some examples, such as... Figure 1 As shown, the height channels are not divided into front and rear; instead, a single channel is used to handle each side (left height and right height). It should also be noted that surround sound systems may have additional or different channels, and / or additional or different transducers.

[0028] Figure 3This is a schematic diagram of a dipole acoustic radiator 80 including an audio transducer 82 with a radiating surface (e.g., a diaphragm) 84. The transducer 82 is mounted to a panel or other support 86 such that the transducer opens forward and backward. When the diaphragm 84 moves up and down, it generates outwardly moving sound pressures along a front principal radiation axis 90 and a rear principal radiation axis 91 that are ideally parallel. For an ideal radiator, the front and rear sound pressures are the same and out of phase. Therefore, the sound cancels out along the two axes (not shown) orthogonal to axes 90 and 91, creating a void at approximately 90 degrees to the principal axes. As is known in the art, a polar diagram of a dipole acoustic radiator looks like a number 8 aligned along the principal axes. In some examples, the dipole acoustic radiator is configured such that the principal radiation axes point in a desired direction or desired location and / or the void points in a desired direction or desired location. In an example of a dipole radiator for the height channel of a soundbar, the main radiating axis points upward toward the ceiling, and the void points outward toward the intended location of the listener (e.g., directly in front of the soundbar, which is intended to be mounted below or above a television). In this example, the sound will hit and reflect off the ceiling, and is therefore perceived as emanating from above the listener, while the void pointing toward the listener helps maintain the perception of height. In an example of a dipole radiator for the left or right channel of a soundbar, the main radiating axis points left or right toward the side wall of the room, and the void points outward toward the intended location of the listener (e.g., directly in front of the soundbar, which is intended to be mounted below or above a television). In this example, the sound will hit or reflect off the left or right wall, and is therefore perceived as emanating from the listener's left or right side, while the void pointing toward the listener helps maintain the perception of left or right. In some examples, the dipole acoustic radiator 80 is used as a transducer for the left height channel, right height channel, left channel, and / or right channel of a soundbar.

[0029] Figure 4 This is a schematic diagram of a dipole acoustic radiator 92 that can be used in a soundbar. The dipole acoustic radiator 92 includes a transducer 95 mounted in a housing 93. The housing 93 includes a top 94 having an opening 96 for emitting front-side radiation. One or more sides and / or the bottom of the housing 93 are sufficiently open such that sound is also emitted from the rear of the transducer. The area and location of the opening from the rear of the transducer to the environment partially determine how close the radiation pattern of the dipole acoustic radiator is to an ideal state, 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 while taking into account any constraints caused by the physical design of the soundbar in which the dipole acoustic radiator 92 is located.

[0030] Figure 5This is a perspective view of a portion of the left end 100 of the housing for a soundbar including a height channel transducer (in this example, a left height channel dipole acoustic radiator (not shown)). The end housing 110 includes an elliptical opening 114 in the top 112, which is configured to hold an elliptical acoustic transducer (not shown) used to generate sound for the dipole acoustic radiator. The ellipse shape is exemplary and does not limit the scope of this disclosure, as the shape of the transducer can be circular, rectangular, or other shapes. In a soundbar using two separate dipole acoustic radiators to reproduce the left and right height channels, the right end (not shown) of the housing may be identical to the left end and also carry a single dipole transducer for the right height channel.

[0031] The housing 110 is also defined by end walls 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 into the environment. The openings can be circular, elliptical, or any shape. In the examples herein, the openings cover 0% to 100% of the wall area. Since both the front and rear sides of the transducer are open to the environment, the transducer will act as a dipole sound radiator. The bottom wall 104 does not include any openings because, in most cases, the soundbar will sit on a surface that would block any such openings. However, the bottom may include an opening. Any one or more of the sides and bottom of the housing 110 may have a desired opening area, such an opening area being achieved by fully open sides or one or more openings of any desired size, shape, and location. In one example, the opening is an elongated slot extending along most of the height of each of the three sides. In one example, the opening extends along most of the periphery of the housing. In some examples, the opening covers at least about 20% of the area of ​​the housing behind the transducer diaphragm to achieve dipole behavior sufficient to reproduce the height channel.

[0032] A small portion 102 of the rest of the soundbar housing is also shown, including a portion of an opening 130 configured to receive a left channel transducer (not shown). The locations of other transducers for the soundbar, such as transducers 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, a dipole radiator is used to reproduce the right height channel, and a separate dipole radiator is used to reproduce the left height channel.

[0033] Figure 6This is a polar graph 150 of the output of the dipole acoustic radiator of the soundbar. Polar graph 150 includes the SPL (in dB) around the transducer over 360 degrees. The zero-degree direction is on the axis of front-side radiation, while the 180-degree direction is on the axis of rear-side radiation. The radiation at 90 degrees and 270 degrees is on an axis orthogonal to the front and rear principal axes, called the void axis. As can be seen, at 250 Hz and 501 Hz, this polar graph is essentially pure dipole, with substantially equal SPL at zero and 180 degrees, and approximately 13 dB or less at 90 and 270 degrees. At 1000 Hz, it begins to shift, and the side void softens to about 8 dB. Above this frequency, the radiator becomes more monopolar (emitting upwards), but the side energy is naturally low, thus still satisfying the goal of a dipole radiator (the SPL pointing upwards towards the ceiling is greater than the SPL directly towards the listener). When the front axis points upwards towards the ceiling, and the void points directly in front of the soundbar, a listener positioned in front of the soundbar will perceive the sound as emanating from the ceiling. The dipole radiator is thus able to reproduce the height channels.

[0034] Figure 7 In relative to, can be similar to Figure 5 The graph shows the sound pressure level across a wide frequency range (100 Hz to approximately 20 kHz) at two corner positions of the dipole acoustic radiator used in the soundbar shown. Plot line 172 along the front principal axis (i.e., at zero degrees on the polar graph) and plot line 174 at 90 degrees. The peak just above 1000 Hz is due to Helmholtz resonance resulting from the combination of the internal volume of the rear housing and the area of ​​the opening to the environment. As can be seen, the virtual axis radiation is smaller than the radiation along the principal axis across the entire spectrum, and at many frequencies, the difference is 5 dB or greater. Figure 8 These are similar graphs 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 locations. In some examples of designs for the left or right height channels, understanding the SPL at 20 degrees and 90 degrees can be useful for understanding the sound that might reflect off the ceiling and reach the listener (20-degree sound) and the sound that might reach the listener directly (90-degree sound). Figure 7 and Figure 8 The curves support quasi-dipole outputs at two angular positions, 70 to 90 degrees apart, relative to the dipole acoustic radiator of the soundbar across the entire frequency range shown.

[0035] In some examples, dipoles are oriented to maintain the maximum difference between the energy directed upward toward the ceiling and the energy directed toward the listener. In such examples, the dipole's directional curve has upward and downward beams and a three-dimensional void in the horizontal plane. The null is fairly narrow and deep, while the upward beam is wide and varies more gradually with angle. If the dipole is angled slightly forward instead of pointing straight up, the energy reflected from the ceiling may be slightly greater (about 1 dB), but the deepest void will not be directed toward the user (in the horizontal plane), thus reducing the benefit of the dipole configuration. Since the slope around the void is much greater than the slope of the upward beam, the maximum difference between these two angles is achieved if the void is in the horizontal plane. Therefore, the maximum difference is usually achieved when the principal axis points directly upward rather than at, for example, a 20-degree angle to the vertical. However, in some specific implementations, the dipole driver may be angled, such as 1 to 30 degrees toward or away from the user, such as 20 degrees toward the user, and even for those angled implementations, the dipole configuration can help improve the directivity of the audio output. The dipole spindle can also be angled slightly to the left or right (e.g., angled towards or away from the center of the soundbar). Outward-pointing dipoles can, for example, extend the apparent width of both height channels. For such configurations, the dipole drivers can be angled from 1 degree inward or outward, such as 20 degrees outward, depending on the desired configuration.

[0036] Dipole drivers are beneficial when used to reproduce audio intended to be spatialized. For example, using one or more dipole drivers can improve audio containing high-frequency components (such as Dolby audio). The output of audio content (or other object-oriented audio content) is improved because using one or more dipole drivers can improve the directionality of the audio output and thus provide a better sense of audio height and / or diffusion.

[0037] Especially in the far field, dipole behavior can lead to low-frequency cancellation, and thus an additional roll-off of approximately 6 dB per octave that should be equalized. Therefore, there are practical limitations on how low a frequency can be driven to drive a dipole transducer, based on the size of the driver and its drift capability. 500 Hz is an approximate practical lower limit for dipole acoustic radiators, with less benefit below approximately 500 Hz, partly because the perception of height is reduced at lower frequencies. In some examples, dipole acoustic radiators are configured to reproduce sound at frequencies where dipole radiation causes a 10 dB to 15 dB loss in low-frequency output, ideally from the highest frequencies down to approximately 500 Hz or below.

[0038] SPL measurements of dipole acoustic radiators can aid in soundbar design, as well as driver placement and orientation, and driver housing design considerations (e.g., rear housing volume and rear opening area). SPL measurements and polar plots provide information for achieving good trade-offs in soundbar and surround sound design. SPL measurements provide information about the frequency response. Furthermore, SPL measurements can be used to determine whether the design achieves good spacing between curves (10dB to 15dB), uniformity of spacing across the frequency range, and a suitable frequency response (relatively smooth and without a low-frequency roll-off that might require excessive boosting).

[0039] The components in the diagram are shown and described as discrete components. These components can be implemented as one or more analog or digital circuits. Alternatively, or otherwise, they can be implemented using one or more microprocessors that execute software instructions. The software instructions may include digital signal processing instructions. Operations can be performed by analog circuits or by a microprocessor executing software that performs equivalent analog operations. Signal lines can be implemented as discrete analog or digital signal lines, discrete digital signal lines with appropriate signal processing capable of handling individual signals, and / or components of wireless communication systems.

[0040] When a process is represented or implied in a block diagram, steps can be performed by one or more elements. Steps can be performed together or at different times. Elements performing activities can be physically identical or close to each other, or they can be physically separated. A single element can perform actions from more than one block. Audio signals can be encoded or unencoded and can be transmitted in digital or analog form. In some cases, conventional audio signal processing equipment and operations are omitted from the diagram.

[0041] Several specific embodiments have been described. However, it should be understood that additional modifications may be made without departing from the scope of the inventive concept described herein, and therefore, other examples are within the scope of the following claims.

Claims

1. A soundbar comprising: 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, and a height audio channel, wherein at least one of the acoustic radiators comprises a dipole acoustic radiator configured to emit sound for the height audio channel in opposite directions along a principal radiation axis, wherein the dipole acoustic radiator has a null toward a desired listening position and transverse to the principal radiation axis; and a main lobe along the principal radiation axis and toward a reflective surface, such that sound reflected from the reflective surface is perceived by a listener as coming from above, and wherein a sound pressure level of the main lobe along the principal radiation axis is greater than a sound pressure level along the null transverse to the principal radiation axis.

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

3. The soundbar of claim 1, further comprising an additional dipole acoustic radiator configured to output sound for the left audio channel or the right audio channel.

4. The soundbar of claim 1, wherein the soundbar further comprises two separate left and right dipole acoustic radiators for the left and right audio channels, respectively, wherein the left dipole acoustic radiator is configured to output sound for the left audio channel, and the right dipole acoustic radiator is configured to output sound for the right audio channel.

5. The soundbar of claim 1, wherein the dipole acoustic radiator comprises an audio driver mounted in a housing such that a front surface of the driver is configured to radiate front sound away from the housing, and an opposite back surface of the driver is configured to radiate back sound into the housing, and wherein the housing defines one or more openings configured to allow the back sound to escape from the housing into an external environment.

6. The soundbar of claim 5, wherein the openings are configured to allow the back sound to escape from the housing along a substantial portion of a perimeter of the housing.

7. The soundbar of claim 5, wherein the openings comprise elongated slots.

8. The soundbar of claim 5, wherein the housing defines two opposite ends and a front side and a back side, and wherein the dipole acoustic radiator is located at one end of the housing such that the housing is located at the one end and the front and back sides adjacent to the one end, and wherein the housing openings are located at the one end and the front and back sides adjacent to the one end.

9. The soundbar of claim 8, comprising two separate dipole sound radiators, one dipole sound radiator at each end of the enclosure such that their housings are at the end and the front and back sides adjacent the respective end, and wherein the housing openings are at the respective end and the front and back sides adjacent the respective end.

10. The soundbar of claim 8, wherein the enclosure defines a height between a bottom side and a top side, and the openings comprise elongated slots extending along a majority of the height of the enclosure.

11. The soundbar of claim 5, wherein the openings encompass at least 20% of the area of the housing.

12. The soundbar of claim 1, wherein the dipole sound radiator sound emission defines a main lobe forward and backward along the main radiation axis.

13. The soundbar of claim 1, wherein the null exhibits a sound pressure level at least 10 dB less than the sound pressure level of the main lobe at one or more sound frequencies.

14. The soundbar of claim 1, wherein the dipole sound radiators are configured to radiate sound at frequencies ranging 500 Hz and above.

15. A soundbar, comprising: an enclosure; and a plurality of sound radiators carried by the enclosure 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, wherein the plurality of sound radiators comprises two separate dipole sound radiators configured to emit sound in opposite directions along a main radiation axis, wherein one of the dipole sound radiators is configured to output sound for the left height audio channel, and the other dipole sound radiator is configured to output sound for the right height audio channel; wherein the dipole sound radiators define a sound emission main lobe forward and backward along their main radiation axis and toward a reflective surface, and further define a null laterally to their main radiation axis and toward a desired listening position, such that sound reflected from the reflective surface is perceived by a listener to be coming from above, wherein the null exhibits a sound pressure level at least 10 dB less than the sound pressure level of the main lobe at one or more sound frequencies.

16. The soundbar of claim 15, wherein the dipole sound radiators each comprise an audio driver mounted in a housing such that a front surface of the driver is configured to radiate forward sound away from the housing, and an opposite back surface of the driver is configured to radiate back sound into the housing, and wherein the housing defines one or more openings configured to allow the back sound to escape from the housing to an outside environment along a majority of a perimeter of the housing.

17. The soundbar of claim 16, wherein the enclosure defines two opposite ends and a front side and a back side, and wherein one of the two separate dipole sound radiators is located at each end of the enclosure such that their housings are located at the end and the front and back sides adjacent the respective end, and wherein the housing opening is located at the respective end and the front and back sides adjacent the respective end.

18. The soundbar of claim 17, wherein the opening of each housing encompasses at least 20% of the area of the housing.

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