Patent Description:
Beam steering audio array systems include multiple speaker drivers and control the gain and delay of the signals sent to the drivers so that their combined effect is to direct acoustic energy so that it favors a particular direction, such as toward a central portion of an audience, and so that it provides certain desirable coverage, so that all members of the audience receive an acceptable audio experience, for example. Traditional array systems may be able to generate two beams by sub-dividing the drivers in the array, using some of the drivers for the formation of a first beam and others of the drivers for formation of a second beam, causing each beam to be less effective than if the entire set of drivers were used. Additionally, traditional array systems may include complex or user-unfriendly methods of changing or adapting the beam steering or other acoustic characteristics of the array, and may include drivers of different sizes to handle different portions of the frequency spectrum at additional cost and complexity with reduced reliability.

<CIT>, <CIT>, <CIT>, <CIT> relate to processing and outputting sound signal.

Aspects and examples are directed to array systems, that provide improved acoustic characteristics, including beam steering and coverage, at lower cost than conventional array systems, and allow creation of multiple steered beams, each generated by the full set of drivers in the array, thus allowing more precise beam shaping.

To this end, the invention proposes an acoustic array system according to claim <NUM>. Further aspects of the invention are defined by the dependent claims.

In some examples, the acoustic transducer array is configured to produce the first driver signal for each of the acoustic transducers based at least in part upon a parameter associated with the first acoustic radiation pattern. The parameter may include a gain, an amplitude, a time delay, a phase delay, a finite impulse response, and/or an equalization. The sound field controller may store the parameter and provide the parameter to the acoustic transducer array.

In certain examples, the sound field controller is configured to select an amplitude and delay of each of the plurality of acoustic transducers to cause the acoustic transducer array to generate the first acoustic radiation pattern. The sound field controller may provide the amplitude and delay of each of the plurality of acoustic transducers to the acoustic transducer array, and the acoustic transducer array may apply the amplitude and delay to each of the plurality of acoustic transducers.

In some examples, the array system includes a second acoustic transducer array configured to receive the first and second processed signals from the first acoustic transducer array.

Still other aspects, examples, and advantages of these exemplary aspects and examples are discussed in detail below. Examples disclosed herein may be combined with other examples in any manner consistent with at least one of the principles disclosed herein, and references to "an example," "some examples," "an alternate example," "various examples," "one example" or the like are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described may be included in at least one example. The appearances of such terms herein are not necessarily all referring to the same example.

Various aspects of at least one example are discussed below with reference to the accompanying figures, which are not intended to be drawn to scale. The figures are included to provide illustration and a further understanding of the various aspects and examples, and are incorporated in and constitute a part of this specification, but are not intended as a definition of the limits of the invention. In the figures, identical or nearly identical components illustrated in various figures may be represented by a like numeral. In the figures:.

Aspects of the present disclosure are directed to acoustic array systems and methods that produce a complex sound field including multiple acoustic radiation patterns, such as two or more beams, by separately processing each beam signal for each driver and superimposing (e.g., adding) the beam signals just prior to providing a combined amplified signal to each driver. Acoustic arrays produce particular radiation patterns by, in most cases, providing individual signals to each driver in the array, where the individual signals vary by one or more of delay, amplitude, phase shift, etc. Calculating and applying individual signal processing per driver to form multiple beams traditionally requires array parameters (delay, amplitude, etc.) per driver that incorporate all the beams, making it difficult to make adjustment to one beam without affecting others, or requiring re-calculation and re-transmission of an extensive set of array coefficients, or else requiring the first beam to be formed by one set of drivers and the second beam to be formed by a second set of drivers, and so on, thus reducing the total number of drivers used to produce each beam as compared to when the array is used to produce only one beam.

The acoustic array systems disclosed herein may include, in some examples, a speaker array coupled to a sound field controller to produce an acoustic sound field having multiple beams. The sound field controller may include and apply signal processing common to all drivers for both beams, and may further apply beam-specific processing, e.g., through two channels, one for each beam, common to all drivers on a per-beam basis. The speaker array may receive two signals, one for each beam, from the sound field controller and may process each received signal separately for each driver, to generate multiple beam signals per driver, i.e., for two beams there are 2N signals in total where N is the number of drivers in the speaker array. Accordingly there is at least a pair of beam signals for each driver. The speaker array further processes the signals to combine all beam signals per driver, and provides each combined signal to a respective driver.

Examples disclosed herein may be combined with other examples in any manner consistent with at least one of the principles disclosed herein, and references to "an example," "some examples," "an alternate example," "various examples," "one example" or the like are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described may be included in at least one example. The appearances of such terms herein are not necessarily all referring to the same example.

It is to be appreciated that examples of the methods and apparatuses discussed herein are not limited in application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The methods and apparatuses are capable of implementation in other examples and of being practiced or of being carried out in various ways. Examples of specific implementations are provided herein for illustrative purposes only and are not intended to be limiting. The use herein of "including," "comprising," "having," "containing," "involving," and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. References to "or" may be construed as inclusive so that any terms described using "or" may indicate any of a single, more than one, and all of the described terms. Any references to front and back, left and right, top and bottom, upper and lower, and vertical and horizontal are intended for convenience of description, not to limit the present systems and methods or their components to any one positional or spatial orientation.

<FIG> illustrates an example of an audio system <NUM> including three speaker arrays <NUM> interconnected in a daisy-chain arrangement, a sound field controller <NUM> in communication with the speaker arrays <NUM> through a network <NUM>, and a user interface <NUM> from which a user <NUM> may operate and control various settings and parameters of the speaker arrays <NUM> to determine characteristics of an acoustic sound field created by the speaker arrays <NUM>. Although three speaker arrays <NUM> are shown, any number of speaker arrays <NUM> may be supported, including additional speaker arrays <NUM> or a single speaker array <NUM>. The sound field controller <NUM> may be in communication with the speaker arrays <NUM> through any suitable communications network <NUM>, which may include a direct interface via wireless or wired interconnection or a network infrastructure including one or more routers, switches, and the like. In a certain example, the sound field controller <NUM> communicates with the speaker arrays <NUM> by a digital audio networking interface, such as Dante™ by Audinate, Inc. , using an Internet Protocol (IP) over any suitable physical layer, e.g., optical, twisted pair, wireless, etc..

The speaker arrays <NUM> each include a number of drivers, which are electroacoustic transducers that convert an electrical audio signal into an acoustic signal, e.g., an acoustic pressure wave. Each driver's acoustic pressure wave ineracts with other drivers' acoustic pressure waves, constructively and destructively interfering at various distances and angles from the speaker array <NUM>, to form a certain acoustic response at each location within a room, and of particular interest at each audience member location within the room. The intensity of the sound at each position in the room, and the intensity variation for different frequencies (e.g., the tone or balance of the sound) is comprehensively referred to herein as a sound field, an acoustic field, or an acoustic sound field.

The sound field controller <NUM> may receive from an audio source <NUM> an audio signal <NUM> that the sound field controller <NUM> processes and passes to the speaker arrays <NUM>. The sound field controller stores system parameters for processing the audio signal <NUM>, such as system gain, system equalizer, and system delay settings, and stores beam settings such as gain and delay parameters for each of the drivers in the speaker arrays <NUM>. The sound field controller <NUM> communicates the delay and gain parameters to the speaker arrays <NUM> via one or more control messages through the communication network <NUM>. For each driver among the speaker arrays <NUM>, a delay and gain applied to the audio signal causes the driver to produce acoustic pressure at the right time and with the right intensity to cause the proper interaction among the acoustic pressure waves to form the intended sound field.

In addition, the sound field controller <NUM> may store finite impulse response (FIR) parameters for each driver. FIR parameters may be stored in the form of a finite impulse response waveform or may be in the form of FIR filter coefficients that, when applied to a FIR filter, produce an associated response to a filtered audio signal. Finite impulse response parameters may provide desired phase delays for different frequencies that a typical time delay (applied equally to all frequencies) could not, but is not necessarily required in all cases. Additionally, finite impulse response parameters may incorporate each of a time delay common to all frequencies, a gain common to all frequencies, and equalization as desired. In certain examples, however, the delay, gain, and equalization for each driver in the speaker arrays <NUM> is managed by separate parameters, and FIR parameters are used to fine tune beam steering and spreading and to make frequency-specific adjustment to the same. In certain examples, FIR parameters are optional or not included.

In addition, the sound field controller <NUM> may store equalization parameters for each driver. The equalization parameters for each driver may include equalization parameters to compensate for a native frequency response of each driver based upon component testing, or the frequency response of each driver in combination with the enclosure and mounting of the driver in the speaker array <NUM>, or the frequency response of the set of all drivers in each speaker array <NUM>, again in combination with the enclosure and mounting of the drivers in the speaker array <NUM>. In the latter case, equalization parameters stored by the sound field controller <NUM> may be identical for each of the drivers within a single speaker array <NUM>, or for all the drivers among all the speaker arrays <NUM>.

In some examples, the speaker array(s) <NUM> may receive array parameters and/or equalization in a different manner. For example, the sound field controller <NUM> in some examples may not store the parameters, or the speaker array(s) <NUM> may not use the parameters or equalization stored by the sound field controller <NUM>, and may use parameters and/or equalization received from elsewhere, such as from a configuration tool, or as previously pre-loaded equalization and/or array parameters stored in memory associated with the speaker array(s) <NUM>.

The sound field controller <NUM> has, or may communicate with, a user interface <NUM> that may include, for example, one or more user input devices such as a keyboard, mouse, touch-sensitive screen, and the like, and may include one or more user output devices, such as a screen, monitor, lights, buzzers, and other indicators, and the like. The user interface <NUM> may be integrated with the sound field controller <NUM>, or may be remote to the sound field controller <NUM> via a direct connection <NUM> or via a network connection <NUM> through the network <NUM> or other suitable communications interface(s). For example, the user interface <NUM> may include a remote computer, workstation, or device, proprietary or non-proprietary, such as a laptop, desktop, tablet, smartphone, etc., and such may have dedicated software that displays user information and options and communicates with the sound field controller <NUM>, or may have general software, such as a web browser, that communicates with the sound field controller <NUM> via e.g., a web server hosted by the sound field controller <NUM>.

The user interface <NUM> may allow a user <NUM> to select a sound field from among multiple pre-loaded sound fields. Additionally, the sound field controller <NUM> coupled with the user interface <NUM> may allow creation of new sound fields by the calculation of new array parameters. In general, signal processing channels of the sound field controller <NUM> and the speaker arrays <NUM>, each discussed in more detail below, process signals to create a desired sound field using array parameters that may include amplitude, gain, time delay, phase delay, equalization, finite impulse response, and other parameters as appropriate to a certain desired sound field. In a certain example, the array parameters applied include amplitude and time delay. In a further example, the array parameters applied also include FIR coefficients.

Such array parameters may be required by the system, e.g., audio system <NUM>, but are generally not "user friendly" in that they are not easily chosen or modified by the user <NUM>. Accordingly, it is desired that the user <NUM> may work with user friendly parameters that define the desired sound field or beam characteristics, such as beam direction, spreading, tonal balance, and the like. Accordingly, a sound field tool may be incorporated into the sound field controller <NUM> to allow calculation of array parameters from user-specified sound field parameters. Alternatively, a sound field tool may exist separate from the sound field controller <NUM>, and the audio system <NUM>, and may provide one or more sets of array parameters that may be loaded, programmed, stored, or otherwise used with the audio system <NUM>. In certain examples, the sound field controller <NUM> may include memory or other storage capability to store such array parameters.

The audio signal <NUM> is described above as coming from an audio source <NUM> and processed by the sound field controller <NUM>. Additionally or alternatively, the sound field controller <NUM> may store one or more portions, or all, of the audio signal <NUM> to be provided to the speaker arrays <NUM>. In other examples, the audio signal <NUM> may be provided to the speaker arrays <NUM> through a different mechanism, such as directly to an audio input associated with one of the speaker arrays <NUM>.

<FIG> illustrates an example of a speaker array <NUM> that includes a number of drivers <NUM> with an array of amplifiers <NUM> and a bank of digital signal processors (DSP) <NUM>. A signal router <NUM> routes an audio signal <NUM>, received at one of a digital interface <NUM> or an analog interface <NUM>, to the DSP bank <NUM> which processes the audio signal <NUM> individually for each driver <NUM> and provides processed signals <NUM>, one for each driver, to the amplifiers <NUM>. The amplifiers <NUM> provide an amplified processed signal <NUM> to each of the drivers <NUM>. A speaker array <NUM> may have any number of drivers <NUM>, amplifiers <NUM>, and DSP's <NUM>.

In a particular example, a speaker array <NUM> has twelve drivers <NUM>, twelve amplifiers <NUM>, and three DSP's <NUM>, each having four DSP channels for a total of twelve DSP channels. Accordingly, there is at least one DSP channel and at least one amplifier channel per driver <NUM> such that each driver <NUM> may receive a unique amplified processed signal <NUM> produced from the received audio signal. Each DSP <NUM> channel applies a delay to the received audio signal <NUM> to provide the processed signal <NUM>, in accord with a delay parameter communicated from the sound field controller <NUM>. Each DSP <NUM> channel may also apply equalization in accord with equalization parameters received from the sound field controller <NUM>, and may additionally or alternatively apply pre-stored equalization in accord with pre-stored equalization parameters. Each DSP <NUM> channel may also apply a gain in accord with a gain parameter received from the sound field controller <NUM>, and may apply a FIR filter in accord with FIR parameters received from the sound field controller <NUM>. In certain examples, gain parameters received from the sound field controller <NUM> are applied by the amplifiers <NUM> instead of, or in addition to, the DSP <NUM> channels.

In certain examples, equalization applied by the DSP <NUM> channels compensates for a frequency response of the speaker array <NUM>, as discussed above. In certain examples, the sound field controller <NUM> may apply equalization to the audio signal <NUM> associated with various frequency responses, such as, for example, to compensate for frequency response of the room in which the speaker array <NUM> is operated, to compensate for tonal balance or frequency coloring anticipated or resulting from the beam forming process (e.g., gain, delay, FIR filters), and/or to apply a user desired equalization, tone adjustment, or color.

Still referring to <FIG>, the speaker array <NUM> may include a controller <NUM> that communicates with and controls the various components of the speaker array <NUM>. For example, the controller <NUM> may be a processor that communicates with the sound field controller <NUM> (via, e.g., digital interface <NUM>) to receive the various array parameters. The controller <NUM> may load or establish the parameters (e.g., gain, delay, FIR) into the DSP <NUM> channels and the amplifiers <NUM>. The controller <NUM> also may control the signal router <NUM> to select the interface upon which to receive the audio signal <NUM>, e.g., digital <NUM> or analog <NUM>, and may receive the audio signal <NUM> from another (e.g., upstream) speaker array <NUM> and/or provide the audio signal <NUM> to another (e.g., downstream) speaker array <NUM> via a daisy-chain input/output interface <NUM>.

Further, the controller <NUM> may detect the presence of upstream and downstream speaker arrays <NUM>, may receive or provide beam forming or array parameters from/to an upstream or downstream speaker array <NUM>, may communicate with the sound field controller <NUM> about the presence of upstream and downstream speaker arrays <NUM>, may receive array parameters or other communications for an upstream or downstream speaker array <NUM> and communicate the parameters to the upstream or downstream speaker array <NUM>, and may receive communication from an upstream or downstream speaker array <NUM> for the sound field controller <NUM> and communicate it to the sound field controller <NUM>. In certain examples, the controller <NUM> may be an integrated component that includes the signal router <NUM> and/or the interfaces <NUM>, <NUM>, <NUM>, and may include or be incorporated in one or more of the DSP's <NUM>. Any suitable processor with suitable programming, or suitable logic, such as an application specific integrated circuit (ASIC), or programmable gate array, for example, may serve as the controller <NUM> or a portion thereof.

<FIG> illustrates a stacked array <NUM> which is a daisy-chained set of speaker arrays <NUM>. A single speaker array <NUM> may be used alone, but certain examples of speaker array systems as disclosed herein allow for daisy-chaining two or more speaker arrays <NUM> to provide a larger array having a greater number of drivers <NUM>, which allows for more extensive control and tailoring of the sound field produced by the stacked array <NUM> than may be achieved by a single speaker array <NUM>. It should be noted that it may not be necessary to form a stacked array <NUM> for all applications or in all situations. The ability to form a stacked array <NUM> may provide increased flexibility to accommodate changing requirements or specific applications. For example, a certain room size or shape may benefit from a stacked array <NUM> to provide more detailed beam forming, while for a smaller room or different shape a single speaker array <NUM> may be sufficient.

The stacked array <NUM> in <FIG> includes a first speaker array 110a, a second speaker array 110b, and a third speaker array 110c. Further examples of a stacked array may include only two speaker arrays <NUM> or may include four or more speaker arrays <NUM>. In the example shown in <FIG>, the first speaker array 110a receives audio and control signals <NUM>, for example as may be received from a sound field controller <NUM> (see <FIG>) as discussed above. The first speaker array 110a communicates via a daisy-chain connection <NUM> with the second speaker array 110b to pass relevant portions of the audio and control signals <NUM> to the second speaker array 110b. Likewise, the second speaker array 110b communicates via a daisy-chain connection <NUM> with the third speaker array 110c to pass relevant portions of the audio and control signals <NUM> to the third speaker array 110c.

Each of the speaker arrays <NUM> may communicate with each other via the daisy-chain connections <NUM>, <NUM>, and the first speaker array 110a may communicate with an audio source (e.g., <FIG>, audio source <NUM>) or a controller (e.g., <FIG>, sound field controller <NUM>). In certain examples, each of the speaker arrays <NUM> may have twelve drivers <NUM> and the stacked array <NUM> may therefore include <NUM> drivers. A sound field controller <NUM> may store and communicate array parameters, e.g., delay, gain, FIR, equalization, etc. for each driver <NUM> in the stacked array <NUM> to produce a selected (e.g., by a user <NUM>) acoustic sound field.

Any of the speaker arrays <NUM> may be in direct communication with a sound field controller <NUM> or an audio source <NUM>, and the terms first, second, and third are used arbitrarily in reference to the speaker arrays <NUM>. For example, the second speaker array 110b could be in communication with the sound field controller <NUM> and receive array parameters, e.g., delay, gain, FIR, equalization, etc. for each driver <NUM> in the stacked array <NUM> and pass along the relevant parameters to the first speaker array 110a and the third speaker array 110c, as appropriate. Similarly, the stacked array <NUM> may be configurable so that any of the three speaker arrays <NUM> may receive an audio signal and pass the audio signal to the other speaker arrays <NUM>, or each of the speaker arrays <NUM> may receive an audio signal directly from an audio source. In certain examples, the physical configuration and communication connectivity of the stacked array <NUM> may be selectable by a user <NUM> at a user interface <NUM>, or may be automatically discoverable by the various systems (e.g., the speaker arrays <NUM> and the sound field controller <NUM>), or any combination thereof.

<FIG> illustrates an example of an audio system <NUM> including at least one speaker array <NUM> in communication with a sound field controller <NUM> through a communications channel, such as may be provided through the network <NUM>. The sound field controller <NUM> stores array parameters <NUM> for the speaker array <NUM> and communicates them to the speaker array <NUM> through one or more control messages <NUM>. The array parameters <NUM> may include gain, delay, FIR, equalization, and other parameters for each of the drivers <NUM> that are part of the speaker array <NUM>. It should be noted that the array parameters <NUM> may include parameters for drivers <NUM> associated with additional speaker arrays <NUM> as part of a stacked array, e.g., the stacked array <NUM> of <FIG>, and one or more of the speaker arrays <NUM> may communicate the array parameters <NUM> through a daisy-chain communication as discussed above.

The array parameters <NUM> may include parameters for beam controls, e.g., steering, direction, spreading, etc., as part of a user-selected sound field and may generally be referred to as beam parameters, though such parameters may effectuate other aspects of sound field creation other than a beam. Additionally, the array parameters <NUM> may include other parameters not associated with a particular beam configuration, such as equalization parameters that compensate for the frequency response of the drivers <NUM> mounted in the speaker array <NUM>.

In certain examples, the sound field controller <NUM> communicates one set of equalization parameters that the speaker array <NUM> applies to all the drivers <NUM>, such as a fixed speaker equalization that compensates for the frequency response of the speaker array <NUM>, which may depend upon a model number or type of speaker array <NUM>. In other examples, the sound field controller <NUM> may communicate different equalization parameters for different drivers <NUM>. For example, drivers <NUM> at different positions in the speaker array <NUM> may exhibit different frequency responses and may benefit from different equalization than other drivers <NUM> in the speaker array <NUM>. Additionally, different user-selected acoustic sound fields may benefit from different equalization in the speaker array <NUM>. Equalization parameters may also be associated with beam control, as a beam pattern may create coloring of the acoustic sound field, i.e., a shifting of frequency response, which may be at least partially compensated by equalization.

The sound field controller <NUM> may apply processing to the audio signal <NUM> to produce a processed audio signal <NUM> that the sound field controller <NUM> passes to the one or more speaker arrays <NUM> (e.g., directly or via a daisy-chain). For example, the sound field controller <NUM> may provide system processing <NUM> that may include gain, delay, equalization, and the like, that affects all sound being produced by the audio system <NUM>. For example, system gain and delay may be beneficial to adjust the overall sound level and timing to match other speakers in a room. For instance, the audio system <NUM> may process and generate a sound field for a rear channel among a set of speakers in a room and the timing and level may need to be adjusted to match a front channel, or vice-versa, or for a left-right channel pair, and the like.

Array parameters such as individual gain, delay, FIR, and equalization parameters for each of the drivers <NUM> may be selected by a sound field design tool that incorporates room characteristics such as shape, size, materials, audience orientation, etc. Such room characteristics may color, i.e., alter the frequency response of, the sound field produced by an acoustic array system, e.g., audio system <NUM>. The sound field controller <NUM> may apply processing <NUM> to adjust the audio signal <NUM> for room characteristics, beam characteristics, or array characteristics that may be at least partially compensated by common processing <NUM> without regard to individual drivers <NUM>. The altered frequency response due to room characteristics, for example, may be at least partially compensated by room equalization applied in the processing <NUM>. Additional coloring of the sound field may be a side product of the array configuration, e.g., the model of one or more speaker arrays <NUM> or configuration as a stacked array <NUM>, or a side product of desired beam characteristics, and such may be at least partially compensated by array and/or beam equalization or other adjustments in the processing <NUM>. Additionally, the sound field controller <NUM> may provide user-selectable options or adjustments to the audio signal, such as equalization, tone, balance, delay, gain, etc, based upon user preferences, and such adjustments may be applied to the audio signal <NUM> in the processing <NUM>. It should be understood that any characteristic, adjustment, or processing of the audio signal <NUM> that does not require individual adjustment at one driver <NUM> separately from another driver <NUM>, may be applied in the sound field controller <NUM> at either of the processing <NUM> or the system processing <NUM>. Such processing that commonly applies to all the drivers <NUM> may be collectively referred to as common processing or system processing.

<FIG> illustrates an example of an audio system <NUM> including at least one speaker array <NUM> in communication with a sound field controller <NUM> configured to produce an acoustic sound field having two beams. Conventional array systems supporting two beams divide the number of drivers into two sets and produce one beam from each set. In some conventional systems that include more than one speaker array the drivers among the various speaker arrays are also divided into two sets and each set is used to provide one beam. This conventional approach uses half as many drivers to produce each beam as compared to a case where only one beam is being produced, thus producing beams having less desirable characteristics, such as less accuracy in the desired or intended beam pattern (e.g., direction, spreading, sidelobes, etc.). An alternate conventional approach includes calculation of a more precise response for each driver in the array to allow extensive control of the sound field produced. Such an approach is computationally challenging, requires significant calculational resources, and may require speaker arrays with significantly increased processing capability to implement the precise response required of each driver. The audio system <NUM>, however, includes a solution that produces two beams, each beam having the precision of using all the drivers in the array, while being cheaper, less complex, and more easily adjustable than conventional, computationally extensive, approaches.

In the audio system <NUM>, the sound field controller <NUM> processes the audio signal <NUM> through two beam processors 430a, 430b to provide two processed audio signals 452a, 452b, one for each beam. The speaker arrays <NUM> include two signal processor channels 230a, 230b per driver <NUM>, one for each beam, that further process the processed audio signals 452a, 452b to provide beam-specific driver signals 254a, 254b. Each beam-specific driver signal 254a, 254b is added together, per driver, by a set of combiners <NUM> to provide combined processed signals <NUM> to the amplifiers <NUM>, which then provide individual amplified signals <NUM> to each of the drivers <NUM>. It should be understood that addition of the beam-specific driver signals 254a, 254b by the combiners <NUM> may be performed within one or more DSP's that implement any of the processer channels <NUM>.

Each beam has its own set of beam-specific parameters, e.g., gain, delay, FIR, equalization, etc. per driver <NUM>, as appropriate for the situation. Each of the beam processors <NUM> associated with the speaker array <NUM> processes one of the beams by applying the respective beam-specific parameters, per driver <NUM>. Accordingly, the sound field controller <NUM> provides two sets of array parameters <NUM> to the speaker array(s) <NUM>, one set of array parameters for the first beam, which are applied to the first set of processor channels 230a, and another set of array parameters for the second beam, which are applied to the second set of processor channels 230b. It should be understood from the above discussion that a speaker array <NUM> in accord with this example has two DSP channels per driver <NUM>, or equivalently stated, each driver <NUM> has two DSP channels, one for each beam to which the driver <NUM> will contribute. The pair of signals produced by the two DSP channels are combined together and the combined signal is amplified before providing to the driver <NUM>.

In such manner, each of the drivers <NUM> of the speaker array(s) <NUM> will produce an acoustic wave that combines with the acoustic waves of all the other drivers <NUM> to produce an acoustic sound field having two beams. Each beam will have the precision or quality of having been produced by all the drivers <NUM> of the array, and not just by a subset of the drivers <NUM>.

A benefit of the example audio system <NUM> is that each beam is individually adjustable within the sound field controller <NUM> (by processors 430a, 430b) or the speaker array <NUM> (by processors 230a, 230b). For example, if the user <NUM> wants to adjust equalization or gain of one of the beams without affecting the other beam, such may be applied in one of the processors <NUM> of the sound field controller <NUM>. In conventional systems individual adjustment to a single beam either requires that each beam be produced only by a subset of the drivers, or requires complex recalculation of array parameters for each driver. For example, in conventional systems that produce multiple beams using all available drivers, the information necessary to produce each beam is intermingled within the driver-specific array parameters, and not separable, thus requiring recalculation of the parameters to create all the beams when it is desired to make a change to only one of the beams. Such requires the speaker array(s) to have increased resources to perform the extensive calculations, or requires the parameters to be calculated elsewhere and transferred, requiring a significant amount of data transmission, to apply the newly calculated parameters.

It should be understood that the example audio system <NUM> processes signals for and produces two beams, but may be extended to any number of beams desired to accommodate varying operational demands or applications. For example, the sound field controller <NUM> may include additional processing <NUM> channels, e.g., beam <NUM> processing 430a, beam <NUM> processing 430b, beam <NUM> processing, and so on up to beam M processing, to provide M number of processed audio signals <NUM>, one for each beam. The speaker array <NUM> may include MxN DSP <NUM> channels to process the M beam signals for each of the N drivers <NUM>, and M combiners <NUM> to add together the M beam-specific driver signals <NUM> to provide N combined signals <NUM>, one for each driver <NUM>.

Among the various examples discussed above reference is made at times to one or more signal processing channels. It should be understood that various signal processing channels may be digital or analog in nature and that specific examples of digital signal processing channels may have analog counterparts substituted therefore, and that analog signal processing may have digital counterparts substituted therefore. It should be understood that conversion of signals from digital to analog, and vice-versa, are well known in the art and such conversion may include one or more digital-to-analog converters (DAC) and/or analog-to-digital converters (ADC), respectively. In the examples discussed above such conversion may be included though the conversion may not be discussed or shown. Those of skill in the art will understand how to make such conversion as necessary to implement the examples discussed. In particular, it should be understood that processing in a sound field controller <NUM>, and in one or more DSP <NUM> channels of a speaker array <NUM>, may occur in the digital domain while a signal (processed, combined, amplified, etc.) provided to an amplifier or to a driver may be analog. Accordingly, a DAC may be provided between, e.g., a DSP <NUM> and an amplifier <NUM>, to convert a processed digital signal into an analog signal to be amplified.

Claim 1:
An acoustic array system (<NUM>) comprising:
a sound field controller (<NUM>) including at least one signal processor configured to process an audio signal (<NUM>) to provide a first processed signal associated with a first acoustic radiation pattern and to provide a second processed signal associated with a second acoustic radiation pattern; and
two or more acoustic transducer arrays (<NUM>) daisy-chained, each including at least one signal processor (<NUM>) and a plurality of acoustic transducers (<NUM>), the acoustic transducer array (<NUM>) configured to receive the first and second processed signals from the sound field controller (<NUM>), produce a first driver signal for each of the acoustic transducers (<NUM>) based upon the first processed signal, produce a second driver signal for each of the acoustic transducers based upon the second processed signal, and combine the first and second driver signals for each of the plurality of acoustic transducers to produce a plurality of combined driver signals, one for each of the acoustic transducers (<NUM>), and provide at least one combined driver signal (<NUM>) to each of the acoustic transducers (<NUM>),
each of the acoustic transducer arrays (<NUM>) is configured to communicate with each other via daisy-chain connections (<NUM>, <NUM>); and
the first acoustic transducer array (<NUM>) is configured to communicate with the sound field controller (<NUM>).