Audio device transducer and associated systems and methods

Audio device transducers are disclosed herein. In some embodiments, the audio device transducer comprises a coil, first and second terminals each disposed adjacent a first side of the coil, and first and second conductors each electrically coupled to the coil. The first conductor extends from the first end of the coil to the first terminal, and the second end extends from a second end of the coil to the second terminal. The second conductor includes a first conductive pathway and a second conductive pathway spaced apart from the first conductive pathway such that the coil is disposed between the first conductive pathway and the second conductive pathway. In some embodiments, the first conductive pathway is symmetric to the second conductive pathway about an axis extending through the coil.

FIELD OF THE DISCLOSURE

BACKGROUND

Options for accessing and listening to digital audio in an out-loud setting were limited until in 2002, when SONOS, Inc. began development of a new type of playback system. Sonos then filed one of its first patent applications in 2003, entitled “Method for Synchronizing Audio Playback between Multiple Networked Devices,” and began offering its first media playback systems for sale in 2005. The Sonos Wireless Home Sound System enables people to experience music from many sources via one or more networked playback devices. Through a software control application installed on a controller (e.g., smartphone, tablet, computer, voice input device), one can play what she wants in any room having a networked playback device. Media content (e.g., songs, podcasts, video sound) can be streamed to playback devices such that each room with a playback device can play back corresponding different media content. In addition, rooms can be grouped together for synchronous playback of the same media content, and/or the same media content can be heard in all rooms synchronously.

The drawings are for the purpose of illustrating example embodiments, but those of ordinary skill in the art will understand that the technology disclosed herein is not limited to the arrangements and/or instrumentality shown in the drawings.

DETAILED DESCRIPTION

Most transducers used within speakers or audio devices include standard components, such as an input source (e.g., from an amplifier), first and second terminals connected to the input source, and a voice coil connected to the first and second terminals via respective first and second leads. Electrical signals provided from the input source to the voice coil generate a magnetic field, thereby causing the voice coil to move and displace a diaphragm attached thereto to produce audible sound. Despite this intended effect, transducers often have deficiencies that generate undesirable noise or electromagnetic interference (EMI) signals, which can thereby make the listener's experience less than optimal and/or result in undesirable levels of electromagnetic radiation. For example, in traditional transducers, the first lead connected to the first terminal extends from a first side of the voice coil, and the second lead connected to the second terminal extends from a second, opposing side of the voice coil. Disposing the first and second ends of the voice coil on opposing sides is preferred for balance purposes, e.g., to ensure the voice coil is not tilted or askew and thereby does not generate undesirable noise. Additionally, the first and second terminals are preferably disposed adjacent one another, e.g., on the same side of the voice coil, as increasing the distance between the first and second terminals may also generate undesirable EMI. In such a configuration, the first lead extends from the first side of the voice coil to the first terminal, and the second lead extends from the second, opposing side of the voice coil to the second terminal, which is adjacent the first terminal. Due to the second lead extending from the second side of the voice coil to the second terminal along one, and only one, side of the voice coil, the second lead in operation can introduce EMI, which is generally undesired for any transducer or corresponding device. For some devices, such EMI can be filtered downstream, e.g., via a filter incorporated with the amplifier. However, as the footprint of devices continues to decrease to meet consumer demand, the ability to include downstream filters or shielding has become more difficult for manufacturers. Additionally, as a result of less downstream filtering or shielding, complying with relevant national, regional and/or international standards for electromagnetic radiation has also become more difficult.

Embodiments of the disclosed technology address at least some of the above described issues associated with transducers, and generally relate to improved transducers, e.g., for use in audio devices. As explained in more detail elsewhere herein, some embodiments of the disclosed technology relate to a transducer or audio device that includes a voice coil, first and second terminals disposed adjacent a first side of the voice coil, a first conductor extending from the first side of the voice coil to the first terminal, and a second conductor extending from a second, opposing side of the voice coil to the second terminal via first and second conductive pathways. The first and second conductive pathways can extend toward the second terminal along opposing sides of the voice coil in a manner that produces little or no net EMI from the corresponding conductors.

In the Figures, identical reference numbers identify generally similar, and/or identical, elements. To facilitate the discussion of any particular element, the most significant digit or digits of a reference number refers to the Figure in which that element is first introduced. For example, element110ais first introduced and discussed with reference toFIG.1A. Many of the details, dimensions, angles and other features shown in the Figures are merely illustrative of particular embodiments of the disclosed technology. Accordingly, other embodiments can have other details, dimensions, angles and features without departing from the spirit or scope of the disclosure. In addition, those of ordinary skill in the art will appreciate that further embodiments of the various disclosed technologies can be practiced without several of the details described below.

II. Suitable Operating Environment

FIG.1Ais a partial cutaway view of a media playback system100distributed in an environment101(e.g., a house). The media playback system100comprises one or more playback devices110(identified individually as playback devices110a-n), one or more network microphone devices (“NMDs”),120(identified individually as NMDs120a-c), and one or more control devices130(identified individually as control devices130aand130b).

As used herein the term “playback device” can generally refer to a network device configured to receive, process, and output data of a media playback system. For example, a playback device can be a network device that receives and processes audio content. In some embodiments, a playback device includes one or more transducers or speakers powered by one or more amplifiers. In other embodiments, however, a playback device includes one of (or neither of) the speaker and the amplifier. For instance, a playback device can comprise one or more amplifiers configured to drive one or more speakers external to the playback device via a corresponding wire or cable.

Moreover, as used herein the term NMD (i.e., a “network microphone device”) can generally refer to a network device that is configured for audio detection. In some embodiments, an NMD is a stand-alone device configured primarily for audio detection. In other embodiments, an NMD is incorporated into a playback device (or vice versa).

The term “control device” can generally refer to a network device configured to perform functions relevant to facilitating user access, control, and/or configuration of the media playback system100.

Each of the playback devices110is configured to receive audio signals or data from one or more media sources (e.g., one or more remote servers, one or more local devices) and play back the received audio signals or data as sound. The one or more NMDs120are configured to receive spoken word commands, and the one or more control devices130are configured to receive user input. In response to the received spoken word commands and/or user input, the media playback system100can play back audio via one or more of the playback devices110. In certain embodiments, the playback devices110are configured to commence playback of media content in response to a trigger. For instance, one or more of the playback devices110can be configured to play back a morning playlist upon detection of an associated trigger condition (e.g., presence of a user in a kitchen, detection of a coffee machine operation). In some embodiments, for example, the media playback system100is configured to play back audio from a first playback device (e.g., the playback device110a) in synchrony with a second playback device (e.g., the playback device110b). Interactions between the playback devices110, NMDs120, and/or control devices130of the media playback system100configured in accordance with the various embodiments of the disclosure are described in greater detail below.

In the illustrated embodiment ofFIG.1A, the environment101comprises a household having several rooms, spaces, and/or playback zones, including (clockwise from upper left) a master bathroom101a, a master bedroom101b, a second bedroom101c, a family room or den101d, an office101e, a living room101f, a dining room101g, a kitchen101h, and an outdoor patio101i. While certain embodiments and examples are described below in the context of a home environment, the technologies described herein may be implemented in other types of environments. In some embodiments, for example, the media playback system100can be implemented in one or more commercial settings (e.g., a restaurant, mall, airport, hotel, a retail or other store), one or more vehicles (e.g., a sports utility vehicle, bus, car, a ship, a boat, an airplane), multiple environments (e.g., a combination of home and vehicle environments), and/or another suitable environment where multi-zone audio may be desirable.

The media playback system100can comprise one or more playback zones, some of which may correspond to the rooms in the environment101. The media playback system100can be established with one or more playback zones, after which additional zones may be added, or removed to form, for example, the configuration shown inFIG.1A. Each zone may be given a name according to a different room or space such as the office101e, master bathroom101a, master bedroom101b, the second bedroom101c, kitchen101h, dining room101g, living room101f, and/or the balcony101i. In some embodiments, a single playback zone may include multiple rooms or spaces. In certain embodiments, a single room or space may include multiple playback zones.

In the illustrated embodiment ofFIG.1A, the master bathroom101a, the second bedroom101c, the office101e, the living room101f, the dining room101g, the kitchen101h, and the outdoor patio101ieach include one playback device110, and the master bedroom101band the den101dinclude a plurality of playback devices110. In the master bedroom101b, the playback devices110land110mmay be configured, for example, to play back audio content in synchrony as individual ones of playback devices110, as a bonded playback zone, as a consolidated playback device, and/or any combination thereof. Similarly, in the den101d, the playback devices110h-jcan be configured, for instance, to play back audio content in synchrony as individual ones of playback devices110, as one or more bonded playback devices, and/or as one or more consolidated playback devices. Additional details regarding bonded and consolidated playback devices are described below with respect toFIGS.1B and1E.

In some embodiments, one or more of the playback zones in the environment101may each be playing different audio content. For instance, a user may be grilling on the patio101iand listening to hip hop music being played by the playback device110cwhile another user is preparing food in the kitchen101hand listening to classical music played by the playback device110b. In another example, a playback zone may play the same audio content in synchrony with another playback zone. For instance, the user may be in the office101elistening to the playback device110fplaying back the same hip hop music being played back by playback device110con the patio101i. In some embodiments, the playback devices110cand110fplay back the hip hop music in synchrony such that the user perceives that the audio content is being played seamlessly (or at least substantially seamlessly) while moving between different playback zones. Additional details regarding audio playback synchronization among playback devices and/or zones can be found, for example, in U.S. Pat. No. 8,234,395 entitled, “System and method for synchronizing operations among a plurality of independently clocked digital data processing devices,” which is incorporated herein by reference in its entirety.

a. Suitable Media Playback System

FIG.1Bis a schematic diagram of the media playback system100and a cloud network102. For ease of illustration, certain devices of the media playback system100and the cloud network102are omitted fromFIG.1B. One or more communication links103(referred to hereinafter as “the links103”) communicatively couple the media playback system100and the cloud network102.

The links103can comprise, for example, one or more wired networks, one or more wireless networks, one or more wide area networks (WAN), one or more local area networks (LAN), one or more personal area networks (PAN), one or more telecommunication networks (e.g., one or more Global System for Mobiles (GSM) networks, Code Division Multiple Access (CDMA) networks, Long-Term Evolution (LTE) networks, 5G communication network networks, and/or other suitable data transmission protocol networks), etc. The cloud network102is configured to deliver media content (e.g., audio content, video content, photographs, social media content) to the media playback system100in response to a request transmitted from the media playback system100via the links103. In some embodiments, the cloud network102is further configured to receive data (e.g. voice input data) from the media playback system100and correspondingly transmit commands and/or media content to the media playback system100.

The cloud network102comprises computing devices106(identified separately as a first computing device106a, a second computing device106b, and a third computing device106c). The computing devices106can comprise individual computers or servers, such as, for example, a media streaming service server storing audio and/or other media content, a voice service server, a social media server, a media playback system control server, etc. In some embodiments, one or more of the computing devices106comprise modules of a single computer or server. In certain embodiments, one or more of the computing devices106comprise one or more modules, computers, and/or servers. Moreover, while the cloud network102is described above in the context of a single cloud network, in some embodiments the cloud network102comprises a plurality of cloud networks comprising communicatively coupled computing devices. Furthermore, while the cloud network102is shown inFIG.1Bas having three of the computing devices106, in some embodiments, the cloud network102comprises fewer (or more than) three computing devices106.

The media playback system100is configured to receive media content from the networks102via the links103. The received media content can comprise, for example, a Uniform Resource Identifier (URI) and/or a Uniform Resource Locator (URL). For instance, in some examples, the media playback system100can stream, download, or otherwise obtain data from a URI or a URL corresponding to the received media content. A network104communicatively couples the links103and at least a portion of the devices (e.g., one or more of the playback devices110, NMDs120, and/or control devices130) of the media playback system100. The network104can include, for example, a wireless network (e.g., a WiFi network, a Bluetooth, a Z-Wave network, a ZigBee, and/or other suitable wireless communication protocol network) and/or a wired network (e.g., a network comprising Ethernet, Universal Serial Bus (USB), and/or another suitable wired communication). As those of ordinary skill in the art will appreciate, as used herein, “WiFi” can refer to several different communication protocols including, for example, Institute of Electrical and Electronics Engineers (IEEE) 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ac, 802.11ad, 802.11af, 802.11ah, 802.11ai, 802.11aj, 802.11aq, 802.11ax, 802.11 ay, 802.15, etc. transmitted at 2.4 Gigahertz (GHz), 5 GHz, and/or another suitable frequency.

In some embodiments, the network104comprises a dedicated communication network that the media playback system100uses to transmit messages between individual devices and/or to transmit media content to and from media content sources (e.g., one or more of the computing devices106). In certain embodiments, the network104is configured to be accessible only to devices in the media playback system100, thereby reducing interference and competition with other household devices. In other embodiments, however, the network104comprises an existing household communication network (e.g., a household WiFi network). In some embodiments, the links103and the network104comprise one or more of the same networks. In some embodiments, for example, the links103and the network104comprise a telecommunication network (e.g., an LTE network, a 5G network). Moreover, in some embodiments, the media playback system100is implemented without the network104, and devices comprising the media playback system100can communicate with each other, for example, via one or more direct connections, PANs, telecommunication networks, and/or other suitable communication links.

In some embodiments, audio content sources may be regularly added or removed from the media playback system100. In some embodiments, for example, the media playback system100performs an indexing of media items when one or more media content sources are updated, added to, and/or removed from the media playback system100. The media playback system100can scan identifiable media items in some or all folders and/or directories accessible to the playback devices110, and generate or update a media content database comprising metadata (e.g., title, artist, album, track length) and other associated information (e.g., URIs, URLs) for each identifiable media item found. In some embodiments, for example, the media content database is stored on one or more of the playback devices110, network microphone devices120, and/or control devices130.

In the illustrated embodiment ofFIG.1B, the playback devices110land110mcomprise a group107a. The playback devices110land110mcan be positioned in different rooms in a household and be grouped together in the group107aon a temporary or permanent basis based on user input received at the control device130aand/or another control device130in the media playback system100. When arranged in the group107a, the playback devices110land110mcan be configured to play back the same or similar audio content in synchrony from one or more audio content sources. In certain embodiments, for example, the group107acomprises a bonded zone in which the playback devices110land110mcomprise left audio and right audio channels, respectively, of multi-channel audio content, thereby producing or enhancing a stereo effect of the audio content. In some embodiments, the group107aincludes additional playback devices110. In other embodiments, however, the media playback system100omits the group107aand/or other grouped arrangements of the playback devices110.

The media playback system100includes the NMDs120aand120d, each comprising one or more microphones configured to receive voice utterances from a user. In the illustrated embodiment ofFIG.1B, the NMD120ais a standalone device and the NMD120dis integrated into the playback device110n. The NMD120a, for example, is configured to receive voice input121from a user123. In some embodiments, the NMD120atransmits data associated with the received voice input121to a voice assistant service (VAS) configured to (i) process the received voice input data and (ii) transmit a corresponding command to the media playback system100. In some embodiments, for example, the computing device106ccomprises one or more modules and/or servers of a VAS (e.g., a VAS operated by one or more of SONOS®, AMAZON®, GOOGLE® APPLE®, MICROSOFT®). The computing device106ccan receive the voice input data from the NMD120avia the network104and the links103. In response to receiving the voice input data, the computing device106cprocesses the voice input data (i.e., “Play Hey Jude by The Beatles”), and determines that the processed voice input includes a command to play a song (e.g., “Hey Jude”). The computing device106caccordingly transmits commands to the media playback system100to play back “Hey Jude” by the Beatles from a suitable media service (e.g., via one or more of the computing devices106) on one or more of the playback devices110.

b. Suitable Playback Devices

FIG.1Cis a block diagram of the playback device110acomprising an input/output111. The input/output111can include an analog I/O111a(e.g., one or more wires, cables, and/or other suitable communication links configured to carry analog signals) and/or a digital I/O111b(e.g., one or more wires, cables, or other suitable communication links configured to carry digital signals). In some embodiments, the analog I/O111ais an audio line-in input connection comprising, for example, an auto-detecting 3.5 mm audio line-in connection. In some embodiments, the digital I/O111bcomprises a Sony/Philips Digital Interface Format (S/PDIF) communication interface and/or cable and/or a Toshiba Link (TOSLINK) cable. In some embodiments, the digital I/O111bcomprises a High-Definition Multimedia Interface (HDMI) interface and/or cable. In some embodiments, the digital I/O111bincludes one or more wireless communication links comprising, for example, a radio frequency (RF), infrared, WiFi, Bluetooth, or another suitable communication protocol. In certain embodiments, the analog I/O111aand the digital111bcomprise interfaces (e.g., ports, plugs, jacks) configured to receive connectors of cables transmitting analog and digital signals, respectively, without necessarily including cables.

The playback device110a, for example, can receive media content (e.g., audio content comprising music and/or other sounds) from a local audio source105via the input/output111(e.g., a cable, a wire, a PAN, a Bluetooth connection, an ad hoc wired or wireless communication network, and/or another suitable communication link). The local audio source105can comprise, for example, a mobile device (e.g., a smartphone, a tablet, a laptop computer) or another suitable audio component (e.g., a television, a desktop computer, an amplifier, a phonograph, a Blu-ray player, a memory storing digital media files). In some embodiments, the local audio source105includes local music libraries on a smartphone, a computer, a networked-attached storage (NAS), and/or another suitable device configured to store media files. In certain embodiments, one or more of the playback devices110, NMDs120, and/or control devices130comprise the local audio source105. In other embodiments, however, the media playback system omits the local audio source105altogether. In some embodiments, the playback device110adoes not include an input/output111and receives all audio content via the network104.

The playback device110afurther comprises electronics112, a user interface113(e.g., one or more buttons, knobs, dials, touch-sensitive surfaces, displays, touchscreens), and one or more transducers114(referred to hereinafter as “the transducers114”). The electronics112is configured to receive audio from an audio source (e.g., the local audio source105) via the input/output111, one or more of the computing devices106a-cvia the network104(FIG.1B)), amplify the received audio, and output the amplified audio for playback via one or more of the transducers114. In some embodiments, the playback device110aoptionally includes one or more microphones115(e.g., a single microphone, a plurality of microphones, a microphone array) (hereinafter referred to as “the microphones115”). In certain embodiments, for example, the playback device110ahaving one or more of the optional microphones115can operate as an NMD configured to receive voice input from a user and correspondingly perform one or more operations based on the received voice input.

In the illustrated embodiment ofFIG.1C, the electronics112comprise one or more processors112a(referred to hereinafter as “the processors112a”), memory112b, software components112c, a network interface112d, one or more audio processing components112g(referred to hereinafter as “the audio components112g”), one or more audio amplifiers112h(referred to hereinafter as “the amplifiers112h”), and power112i(e.g., one or more power supplies, power cables, power receptacles, batteries, induction coils, Power-over Ethernet (POE) interfaces, and/or other suitable sources of electric power). In some embodiments, the electronics112optionally include one or more other components112j(e.g., one or more sensors, video displays, touchscreens, battery charging bases).

The processors112acan comprise clock-driven computing component(s) configured to process data, and the memory112bcan comprise a computer-readable medium (e.g., a tangible, non-transitory computer-readable medium, data storage loaded with one or more of the software components112c) configured to store instructions for performing various operations and/or functions. The processors112aare configured to execute the instructions stored on the memory112bto perform one or more of the operations. The operations can include, for example, causing the playback device110ato retrieve audio data from an audio source (e.g., one or more of the computing devices106a-c(FIG.1B)), and/or another one of the playback devices110. In some embodiments, the operations further include causing the playback device110ato send audio data to another one of the playback devices110aand/or another device (e.g., one of the NMDs120). Certain embodiments include operations causing the playback device110ato pair with another of the one or more playback devices110to enable a multi-channel audio environment (e.g., a stereo pair, a bonded zone).

The processors112acan be further configured to perform operations causing the playback device110ato synchronize playback of audio content with another of the one or more playback devices110. As those of ordinary skill in the art will appreciate, during synchronous playback of audio content on a plurality of playback devices, a listener will preferably be unable to perceive time-delay differences between playback of the audio content by the playback device110aand the other one or more other playback devices110. Additional details regarding audio playback synchronization among playback devices can be found, for example, in U.S. Pat. No. 8,234,395, which was incorporated by reference above.

In some embodiments, the memory112bis further configured to store data associated with the playback device110a, such as one or more zones and/or zone groups of which the playback device110ais a member, audio sources accessible to the playback device110a, and/or a playback queue that the playback device110a(and/or another of the one or more playback devices) can be associated with. The stored data can comprise one or more state variables that are periodically updated and used to describe a state of the playback device110a. The memory112bcan also include data associated with a state of one or more of the other devices (e.g., the playback devices110, NMDs120, control devices130) of the media playback system100. In some embodiments, for example, the state data is shared during predetermined intervals of time (e.g., every 5 seconds, every 10 seconds, every 60 seconds) among at least a portion of the devices of the media playback system100, so that one or more of the devices have the most recent data associated with the media playback system100.

The network interface112dis configured to facilitate a transmission of data between the playback device110aand one or more other devices on a data network such as, for example, the links103and/or the network104(FIG.1B). The network interface112dis configured to transmit and receive data corresponding to media content (e.g., audio content, video content, text, photographs) and other signals (e.g., non-transitory signals) comprising digital packet data including an Internet Protocol (IP)-based source address and/or an IP-based destination address. The network interface112dcan parse the digital packet data such that the electronics112properly receives and processes the data destined for the playback device110a.

In the illustrated embodiment ofFIG.1C, the network interface112dcomprises one or more wireless interfaces112e(referred to hereinafter as “the wireless interface112e”). The wireless interface112e(e.g., a suitable interface comprising one or more antennae) can be configured to wirelessly communicate with one or more other devices (e.g., one or more of the other playback devices110, NMDs120, and/or control devices130) that are communicatively coupled to the network104(FIG.1B) in accordance with a suitable wireless communication protocol (e.g., WiFi, Bluetooth, LTE). In some embodiments, the network interface112doptionally includes a wired interface112f(e.g., an interface or receptacle configured to receive a network cable such as an Ethernet, a USB-A, USB-C, and/or Thunderbolt cable) configured to communicate over a wired connection with other devices in accordance with a suitable wired communication protocol. In certain embodiments, the network interface112dincludes the wired interface112fand excludes the wireless interface112e. In some embodiments, the electronics112excludes the network interface112daltogether and transmits and receives media content and/or other data via another communication path (e.g., the input/output111).

The audio components112gare configured to process and/or filter data comprising media content received by the electronics112(e.g., via the input/output111and/or the network interface112d) to produce output audio signals. In some embodiments, the audio processing components112gcomprise, for example, one or more digital-to-analog converters (DAC), audio preprocessing components, audio enhancement components, a digital signal processors (DSPs), and/or other suitable audio processing components, modules, circuits, etc. In certain embodiments, one or more of the audio processing components112gcan comprise one or more subcomponents of the processors112a. In some embodiments, the electronics112omits the audio processing components112g. In some embodiments, for example, the processors112aexecute instructions stored on the memory112bto perform audio processing operations to produce the output audio signals.

The amplifiers112hare configured to receive and amplify the audio output signals produced by the audio processing components112gand/or the processors112a. The amplifiers112hcan comprise electronic devices and/or components configured to amplify audio signals to levels sufficient for driving one or more of the transducers114. In some embodiments, for example, the amplifiers112hinclude one or more switching or class-D power amplifiers. In other embodiments, however, the amplifiers include one or more other types of power amplifiers (e.g., linear gain power amplifiers, class-A amplifiers, class-B amplifiers, class-AB amplifiers, class-C amplifiers, class-D amplifiers, class-E amplifiers, class-F amplifiers, class-G and/or class H amplifiers, and/or another suitable type of power amplifier). In certain embodiments, the amplifiers112hcomprise a suitable combination of two or more of the foregoing types of power amplifiers. Moreover, in some embodiments, individual ones of the amplifiers112hcorrespond to individual ones of the transducers114. In other embodiments, however, the electronics112includes a single one of the amplifiers112hconfigured to output amplified audio signals to a plurality of the transducers114. In some other embodiments, the electronics112omits the amplifiers112h.

The transducers114(e.g., one or more speakers and/or speaker drivers) receive the amplified audio signals from the amplifier112hand render or output the amplified audio signals as sound (e.g., audible sound waves having a frequency between about 20 Hertz (Hz) and 20 kilohertz (kHz)). In some embodiments, the transducers114can comprise a single transducer. In other embodiments, however, the transducers114comprise a plurality of audio transducers. In some embodiments, the transducers114comprise more than one type of transducer. For example, the transducers114can include one or more low frequency transducers (e.g., subwoofers, woofers), mid-range frequency transducers (e.g., mid-range transducers, mid-woofers), and one or more high frequency transducers (e.g., one or more tweeters). As used herein, “low frequency” can generally refer to audible frequencies below about 500 Hz, “mid-range frequency” can generally refer to audible frequencies between about 500 Hz and about 2 kHz, and “high frequency” can generally refer to audible frequencies above 2 kHz. In certain embodiments, however, one or more of the transducers114comprise transducers that do not adhere to the foregoing frequency ranges. For example, one of the transducers114may comprise a mid-woofer transducer configured to output sound at frequencies between about 200 Hz and about 5 kHz.

By way of illustration, SONOS, Inc. presently offers (or has offered) for sale certain playback devices including, for example, a “SONOS ONE,” “MOVE,” “PLAY:5,” “BEAM,” “PLAYBAR,” “PLAYBASE,” “PORT,” “BOOST,” “AMP,” and “SUB.” Other suitable playback devices may additionally or alternatively be used to implement the playback devices of example embodiments disclosed herein. Additionally, one of ordinary skilled in the art will appreciate that a playback device is not limited to the examples described herein or to SONOS product offerings. In some embodiments, for example, one or more playback devices110comprises wired or wireless headphones (e.g., over-the-ear headphones, on-ear headphones, in-ear earphones). In other embodiments, one or more of the playback devices110comprise a docking station and/or an interface configured to interact with a docking station for personal mobile media playback devices. In certain embodiments, a playback device may be integral to another device or component such as a television, a lighting fixture, or some other device for indoor or outdoor use. In some embodiments, a playback device omits a user interface and/or one or more transducers. For example,FIG.1Dis a block diagram of a playback device110pcomprising the input/output111and electronics112without the user interface113or transducers114.

FIG.1Eis a block diagram of a bonded playback device110qcomprising the playback device110a(FIG.1C) sonically bonded with the playback device110i(e.g., a subwoofer) (FIG.1A). In the illustrated embodiment, the playback devices110aand110iare separate ones of the playback devices110housed in separate enclosures. In some embodiments, however, the bonded playback device110qcomprises a single enclosure housing both the playback devices110aand110i. The bonded playback device110qcan be configured to process and reproduce sound differently than an unbonded playback device (e.g., the playback device110aofFIG.1C) and/or paired or bonded playback devices (e.g., the playback devices110land110mofFIG.1B). In some embodiments, for example, the playback device110ais full-range playback device configured to render low frequency, mid-range frequency, and high frequency audio content, and the playback device110iis a subwoofer configured to render low frequency audio content. In some embodiments, the playback device110a, when bonded with the first playback device, is configured to render only the mid-range and high frequency components of a particular audio content, while the playback device110irenders the low frequency component of the particular audio content. In some embodiments, the bonded playback device110qincludes additional playback devices and/or another bonded playback device. Additional playback device embodiments are described in further detail below with respect toFIGS.2A-2C.

c. Suitable Network Microphone Devices (NMDs)

FIG.1Fis a block diagram of the NMD120a(FIGS.1A and1B). The NMD120aincludes one or more voice processing components124(hereinafter “the voice components124”) and several components described with respect to the playback device110a(FIG.1C) including the processors112a, the memory112b, and the microphones115. The NMD120aoptionally comprises other components also included in the playback device110a(FIG.1C), such as the user interface113and/or the transducers114. In some embodiments, the NMD120ais configured as a media playback device (e.g., one or more of the playback devices110), and further includes, for example, one or more of the audio components112g(FIG.1C), the amplifiers114, and/or other playback device components. In certain embodiments, the NMD120acomprises an Internet of Things (IoT) device such as, for example, a thermostat, alarm panel, fire and/or smoke detector, etc. In some embodiments, the NMD120acomprises the microphones115, the voice processing components124, and only a portion of the components of the electronics112described above with respect toFIG.1B. In some embodiments, for example, the NMD120aincludes the processor112aand the memory112b(FIG.1B), while omitting one or more other components of the electronics112. In some embodiments, the NMD120aincludes additional components (e.g., one or more sensors, cameras, thermometers, barometers, hygrometers).

In some embodiments, an NMD can be integrated into a playback device.FIG.1Gis a block diagram of a playback device110rcomprising an NMD120d. The playback device110rcan comprise many or all of the components of the playback device110aand further include the microphones115and voice processing components124(FIG.1F). The playback device110roptionally includes an integrated control device130c. The control device130ccan comprise, for example, a user interface (e.g., the user interface113ofFIG.1B) configured to receive user input (e.g., touch input, voice input) without a separate control device. In other embodiments, however, the playback device110rreceives commands from another control device (e.g., the control device130aofFIG.1B).

Referring again toFIG.1F, the microphones115are configured to acquire, capture, and/or receive sound from an environment (e.g., the environment101ofFIG.1A) and/or a room in which the NMD120ais positioned. The received sound can include, for example, vocal utterances, audio played back by the NMD120aand/or another playback device, background voices, ambient sounds, etc. The microphones115convert the received sound into electrical signals to produce microphone data. The voice processing124receives and analyzes the microphone data to determine whether a voice input is present in the microphone data. The voice input can comprise, for example, an activation word followed by an utterance including a user request. As those of ordinary skill in the art will appreciate, an activation word is a word or other audio cue that signifying a user voice input. For instance, in querying the AMAZON® VAS, a user might speak the activation word “Alexa.” Other examples include “Ok, Google” for invoking the GOOGLE® VAS and “Hey, Siri” for invoking the APPLE® VAS.

After detecting the activation word, voice processing124monitors the microphone data for an accompanying user request in the voice input. The user request may include, for example, a command to control a third-party device, such as a thermostat (e.g., NEST® thermostat), an illumination device (e.g., a PHILIPS HUE® lighting device), or a media playback device (e.g., a Sonos® playback device). For example, a user might speak the activation word “Alexa” followed by the utterance “set the thermostat to 68 degrees” to set a temperature in a home (e.g., the environment101ofFIG.1A). The user might speak the same activation word followed by the utterance “turn on the living room” to turn on illumination devices in a living room area of the home. The user may similarly speak an activation word followed by a request to play a particular song, an album, or a playlist of music on a playback device in the home.

d. Suitable Control Devices

FIG.1His a partially schematic diagram of the control device130a(FIGS.1A and1B). As used herein, the term “control device” can be used interchangeably with “controller” or “control system.” Among other features, the control device130ais configured to receive user input related to the media playback system100and, in response, cause one or more devices in the media playback system100to perform an action(s) or operation(s) corresponding to the user input. In the illustrated embodiment, the control device130acomprises a smartphone (e.g., an iPhone™, an Android phone) on which media playback system controller application software is installed. In some embodiments, the control device130acomprises, for example, a tablet (e.g., an iPad™), a computer (e.g., a laptop computer, a desktop computer), and/or another suitable device (e.g., a television, an automobile audio head unit, an IoT device). In certain embodiments, the control device130acomprises a dedicated controller for the media playback system100. In other embodiments, as described above with respect toFIG.1G, the control device130ais integrated into another device in the media playback system100(e.g., one more of the playback devices110, NMDs120, and/or other suitable devices configured to communicate over a network).

The control device130aincludes electronics132, a user interface133, one or more speakers134, and one or more microphones135. The electronics132comprise one or more processors132a(referred to hereinafter as “the processors132a”), a memory132b, software components132c, and a network interface132d. The processor132acan be configured to perform functions relevant to facilitating user access, control, and configuration of the media playback system100. The memory132bcan comprise data storage that can be loaded with one or more of the software components executable by the processor132ato perform those functions. The software components132ccan comprise applications and/or other executable software configured to facilitate control of the media playback system100. The memory112bcan be configured to store, for example, the software components132c, media playback system controller application software, and/or other data associated with the media playback system100and the user.

The network interface132dis configured to facilitate network communications between the control device130aand one or more other devices in the media playback system100, and/or one or more remote devices. In some embodiments, the network interface132is configured to operate according to one or more suitable communication industry standards (e.g., infrared, radio, wired standards including IEEE 802.3, wireless standards including IEEE 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.15, 4G, LTE). The network interface132dcan be configured, for example, to transmit data to and/or receive data from the playback devices110, the NMDs120, other ones of the control devices130, one of the computing devices106ofFIG.1B, devices comprising one or more other media playback systems, etc. The transmitted and/or received data can include, for example, playback device control commands, state variables, playback zone and/or zone group configurations. For instance, based on user input received at the user interface133, the network interface132dcan transmit a playback device control command (e.g., volume control, audio playback control, audio content selection) from the control device130to one or more of the playback devices110. The network interface132dcan also transmit and/or receive configuration changes such as, for example, adding/removing one or more playback devices110to/from a zone, adding/removing one or more zones to/from a zone group, forming a bonded or consolidated player, separating one or more playback devices from a bonded or consolidated player, among others.

The user interface133is configured to receive user input and can facilitate control of the media playback system100. The user interface133includes media content art 133a (e.g., album art, lyrics, videos), a playback status indicator133b(e.g., an elapsed and/or remaining time indicator), media content information region133c, a playback control region133d, and a zone indicator133e. The media content information region133ccan include a display of relevant information (e.g., title, artist, album, genre, release year) about media content currently playing and/or media content in a queue or playlist. The playback control region133dcan include selectable (e.g., via touch input and/or via a cursor or another suitable selector) icons to cause one or more playback devices in a selected playback zone or zone group to perform playback actions such as, for example, play or pause, fast forward, rewind, skip to next, skip to previous, enter/exit shuffle mode, enter/exit repeat mode, enter/exit cross fade mode, etc. The playback control region133dmay also include selectable icons to modify equalization settings, playback volume, and/or other suitable playback actions. In the illustrated embodiment, the user interface133comprises a display presented on a touch screen interface of a smartphone (e.g., an iPhone™, an Android phone). In some embodiments, however, user interfaces of varying formats, styles, and interactive sequences may alternatively be implemented on one or more network devices to provide comparable control access to a media playback system.

The one or more speakers134(e.g., one or more transducers) can be configured to output sound to the user of the control device130a. In some embodiments, the one or more speakers comprise individual transducers configured to correspondingly output low frequencies, mid-range frequencies, and/or high frequencies. In some embodiments, for example, the control device130ais configured as a playback device (e.g., one of the playback devices110). Similarly, in some embodiments the control device130ais configured as an NMD (e.g., one of the NMDs120), receiving voice commands and other sounds via the one or more microphones135.

The one or more microphones135can comprise, for example, one or more condenser microphones, electret condenser microphones, dynamic microphones, and/or other suitable types of microphones or transducers. In some embodiments, two or more of the microphones135are arranged to capture location information of an audio source (e.g., voice, audible sound) and/or configured to facilitate filtering of background noise. Moreover, in certain embodiments, the control device130ais configured to operate as playback device and an NMD. In other embodiments, however, the control device130aomits the one or more speakers134and/or the one or more microphones135. For instance, the control device130amay comprise a device (e.g., a thermostat, an IoT device, a network device) comprising a portion of the electronics132and the user interface133(e.g., a touch screen) without any speakers or microphones.

III. Example Systems and Devices

FIG.2Ais a front isometric view of a playback device210configured in accordance with embodiments of the disclosed technology.FIG.2Bis a front isometric view of the playback device210without a grille216e.FIG.2Cis an exploded view of the playback device210. Referring toFIGS.2A-2Ctogether, the playback device210comprises a housing216that includes an upper portion216a, a right or first side portion216b, a lower portion216c, a left or second side portion216d, the grille216e, and a rear portion216fA plurality of fasteners216g(e.g., one or more screws, rivets, clips) attaches a frame216hto the housing216. A cavity216j(FIG.2C) in the housing216is configured to receive the frame216hand electronics212. The frame216his configured to carry a plurality of transducers214(identified individually inFIG.2Bas transducers214a-f). The electronics212(e.g., the electronics112ofFIG.1C) is configured to receive audio content from an audio source and send electrical signals corresponding to the audio content to the transducers214for playback.

The transducers214are configured to receive the electrical signals from the electronics112, and further configured to convert the received electrical signals into audible sound during playback. For instance, the transducers214a-c(e.g., tweeters) can be configured to output high frequency sound (e.g., sound waves having a frequency greater than about 2 kHz). The transducers214d-f(e.g., mid-woofers, woofers, midrange speakers) can be configured output sound at frequencies lower than the transducers214a-c(e.g., sound waves having a frequency lower than about 2 kHz). In some embodiments, the playback device210includes a number of transducers different than those illustrated inFIGS.2A-2C. For example, as described in further detail below with respect toFIGS.3A-3C, the playback device210can include fewer than six transducers (e.g., one, two, three). In other embodiments, however, the playback device210includes more than six transducers (e.g., nine, ten). Moreover, in some embodiments, all or a portion of the transducers214are configured to operate as a phased array to desirably adjust (e.g., narrow or widen) a radiation pattern of the transducers214, thereby altering a user's perception of the sound emitted from the playback device210.

In the illustrated embodiment ofFIGS.2A-2C, a filter216iis axially aligned with the transducer214b. The filter216ican be configured to desirably attenuate a predetermined range of frequencies that the transducer214boutputs to improve sound quality and a perceived sound stage output collectively by the transducers214. In some embodiments, however, the playback device210omits the filter216i. In other embodiments, the playback device210includes one or more additional filters aligned with the transducers214band/or at least another of the transducers214.

FIG.3is a partially schematic cutaway view of a transducer300configured in accordance with embodiments of the disclosed technology. The transducer300can correspond to any one of the transducers114,214described elsewhere herein. The transducer300can include standard audio device components, such as a diaphragm302, a basket304, a suspension306connecting the basket304to the diaphragm302, a dust cap308, a tubular member310(e.g., former or a plastic material), a voice coil320helically wound around the tubular member310and configured to move the diaphragm via a magnetic field, a magnet312disposed around the voice coil320, and a spider314attached to the basket304and which maintains tension on the voice coil320. As shown inFIG.3, the basket304can be disposed around a periphery of the transducer300and generally support the other components of the transducer300. The tubular member310may be disposed on and/or around a pole piece (not shown) which directs the magnetic field of the voice coil320to produce a desired audio. The transducer300can also include a first conductor325that electrically couples the voice coil320to a first terminal340a(e.g., a negative terminal), and a second conductor330that electrically couples the voice coil320to a second terminal340b(e.g., a positive terminal).

In some transducers, including those designed particularly for audio devices, the first conductor325connected to the first terminal340aextends from a first end of the voice coil320, and the second conductor330connected to the second terminal340bextends from a second, opposing end of the voice coil320. As explained elsewhere herein, disposing the first and second ends of the voice coil320at opposing sides of the voice coil320is often preferred for balance purposes. That is, disposing both ends of the voice coil320on the same side would cause the voice coil320to be unbalanced, e.g., due to the weight of (i) the first and second conductors325,330connected to the voice coil320, and/or (ii) the adhesive used to terminate the first and second conductors325,330to the voice coil320. This unbalance may result in the voice coil320tilting or otherwise becoming askew, thereby causing less desirable performance (e.g., audio output). Additionally, and as explained elsewhere herein, the first and second terminals340a-bare preferably disposed adjacent one another, e.g., on the same side of the voice coil320. For example, the first and second terminals340a-bcan be spaced apart from one another by less than approximately 15 degrees, 30 degrees, 60 degrees, 90 degrees, 120 degrees or 180 degrees, or any increment therebetween (e.g., 45 degrees) with respect to a center of the voice coil320. If the first and second terminals340a-bwere separated from one another, the input leads connected to such terminals may effectively form an antenna and contribute noise and/or undesirable EMI signals. In view of the above, in some transducers, the first conductor325extends from the first side of the voice coil320to the first terminal340a(also on the first side), and the second conductor330extends from the second, opposing side of the voice coil320to the second terminal, which is also disposed on the first side of the voice coil320. In operation and as previously described, the second conductor330in such embodiments introduces EMI, which is generally undesirable for any transducer or corresponding audio device. For some devices, such EMI can be filtered downstream, e.g., via a filter incorporated with the amplifier. However, as devices continue to decrease in size, the ability to include downstream filters or shielding is more difficult.

As shown inFIG.3, the first and second conductors325,330are wires, which can be made from tinsel or any other suitable material(s) (e.g., material(s) having a relatively high mechanical flexibility). In some embodiments, the first and second conductors325,330can include a conductive material such as tinsel, copper, lead, silver, or alloys thereof. Additionally or alternatively, at least a portion of the first and second conductors325,330can be molded or formed into the basket304and/or baffle (not shown) of the transducer300or corresponding audio device. In such embodiments, the conductive material molded or formed into the basket304or baffle is electrically coupled to the voice coil320. The first and second terminals340a-bcan be configured to electrically couple the voice coil320to an input source, such as wires from an amplifier (e.g., a filterless amplifier). In some embodiments, the first and second terminals340a-bcan be molded or formed into the basket304and/or baffle of the transducer300or corresponding audio device.

FIG.4is a partially schematic top-down view of a transducer400configured in accordance with embodiments of the disclosed technology. The transducer400may correspond to a portion of the transducer300(FIG.3) previously described. As shown inFIG.4, the transducer400includes the (i) voice coil320wrapped around the tubular member310, (ii) the first conductor325connected to a first end405of the voice coil320and electrically coupling the voice coil320to the first terminal340a, and (iii) the second conductor330connected to a second end410of the voice coil320and electrically coupling the voice coil320to the second terminal340b. The first and second ends405,410may be disposed on opposing sides415a,415bof the voice coil320. Additionally or alternatively, the first and second conductors325,330can extend from the voice coil320in substantially opposite directions relative to one another (e.g., between about 135 and 225 degrees from each other, between about 160 degrees and about 200 degrees from each other, and/or about 180 degrees from each other). That is, the first conductor325can extend in a first direction toward the first terminal340aand the second conductor330can extend in a second, substantially opposite direction away from the first terminal340aand/or voice coil320. The first conductor325and the second conductor330or a portion thereof (e.g., the first portion430, the second portion435a, or the third portion435b) can be disposed in the same of different vertical planes as one another. For example, when in different vertical plans from one another, the first conductor325may be above or below, and therein vertically spaced apart from, the second conductor330or a portion thereof.

The second conductor330can include multiple portions, including a first portion430extending from the voice coil320to a junction432, a second portion435aextending from the junction432to the second terminal340b, and a third portion435bextending from the junction432to the second terminal340b. The second and third portions435a-bcan be substantially identical to one another in material, thickness, length, shape, and/or pathway, amongst other properties characteristics. The junction432can be a common point that couples (e.g., via soldering or fusing) the first, second, and third portions430,435a,435btogether. The second portion435acan correspond to a first conductive pathway for directing or flowing current between the second terminal340band the voice coil320, and the third portion435bcan correspond to a second conductive pathway for directing or flowing current between the second terminal340band the voice coil320. The second portion435aand first conductive pathway can be disposed on one side415cof the voice coil320, and the third portion435band second conductive pathway can be disposed on an opposing side415dof the voice coil320. In some embodiments, the second and third portions435a-bare symmetric to one another about an axis (A). In such embodiments, the second and third portions may in operation flow a substantially equal amount of current therethrough, e.g., in the same direction. As shown inFIG.4, the axis (A) can extend through one or more of: the first and second terminals340a-b, the first conductor325, the voice coil320, and/or at least a portion (e.g., the first portion430) of the second conductor330. Additionally or alternatively, the second and third portions435a-bcan form an oval or elliptical shape (as opposed to a circular shape), which may be particularly suitable for portable and/or smaller devices (e.g., portable audio devices or speakers) having a more elongate configuration or dimension.

The first and second terminals340a-bare disposed adjacent one another on the same side (e.g., the side415a) of the voice coil320. As described elsewhere herein, in some embodiments it is generally desirable to position the first and second terminals340a-badjacent one another such that the input leads connected to the terminals do not form an antenna and/or cause EMI or radiofrequency emissions therefrom. As such, there may be disadvantages to positioning the first and second terminals340a-bon opposite sides (e.g., sides415a-b) of the voice coil320. As shown inFIG.4, the first terminal340amay be positioned peripheral to the second terminal340band horizontally further away from the voice coil320. The second terminal340bmay be disposed on the same or different vertical plane than that of the first terminal340a. When disposed in different vertical planes, the first and second terminals340a-b may be disposed such that (i) one of the first and second terminals340a-bis vertically over the other of the first and second terminals340a-b, and/or (ii) the first and second terminals340a-bare horizontally spaced apart from the voice coil320by an equal distance.

The first and second terminals340a-b, the voice coil320, and the first and second conductors325,330form an electrical circuit. As noted previously, an input source can be electrically coupled to the first and second terminals340a-b. In operation, the current can flow (i) from the second terminal340bto the junction432via the second and third portions435a-b(i.e., the first and second conductive pathways, respectively), (ii) from the junction432to the first end410via the first portion430, (iii) from the first end410to the second end405, and (iv) from the second end405to the first terminal340avia the first conductor325. In some embodiments, the current can flow in an opposite direction to that previously described. In such and other embodiments, current (e.g., a first current) can flow between the second terminal340band the junction432(via the second and third portions435a-b) in a first general direction, and current (e.g., a second current) can flow between the junction432and the first terminal340a(via the first portion430, voice coil320, and first conductor325) in a second general direction that is opposite the first general direction. In doing so, the electromagnetic field produced via the first current can cancel (e.g., destructively interfere with) all or at least a portion of the electromagnetic field produced via the second current. That is, the electromagnetic field produced via the first current traveling from the second terminal340bto the junction432via the second and third portions435a-bcan cancel or reduce all or at least a portion of the electromagnetic field produced via the second current traveling from the junction432to the first terminal340avia the first portion430, voice coil320, and first conductor325. In doing so, less or no EMI may be produced via the transducer400or corresponding audio device, relative to other transducers that do not include such an arrangement. Accordingly, embodiments of the disclosed technology address or at least mitigate the deficiencies of other transducers, in which EMI is introduced via one of the conductors extending along only one side of the voice coil. Reducing or eliminating the EMI can also remove the need to include downstream filters and/or shielding components, which would be needed with conventional transducers to reduce the EMI. Eliminating the need for downstream filtering and/or shielding can decrease manufacturing costs for the transducers and corresponding devices, and enable the devices to have a smaller footprint without sacrificing audio quality. In some embodiments, operating the transducer300with the second and third portions435a-b, as described herein, can reduce emission of electromagnetic radiation by at least 5-10 decibels relative to other transducers that do not include the second and third portions435a-b.-

FIG.5is a flow diagram of a method500of operating a transducer or audio device configured in accordance with embodiments of the disclosed technology. The method500can include providing a transducer (e.g., the transducer300or400) or audio device comprising a coil (e.g. the voice coil320), a first terminal (e.g., the first terminal340a), a second terminal (e.g., the second terminal340b) adjacent the first terminal, a first conductor (e.g., the first conductor325) extending from a first end (e.g., the first end405) of the voice coil to the first terminal, and a second conductor (e.g., the second conductor330) extending from a second end (e.g., the second end410) of the voice coil to the second terminal (process portion502). The method500further comprises flowing current between the first terminal and the coil via the first conductor (process portion504), and flowing current between the second terminal and the coil via the second conductor along first and second conductive pathways (e.g., the second and third portions435a-b, respectively) that extend toward the second terminal via opposing sides of the coil (process portion506). In some embodiments, the first and second conductive pathways may be symmetric or mirrored reflections of one another about an axis (e.g., the axis (A)) extending through the voice coil and/or the portion of the second conductor extending directly from the voice coil. Additionally or alternatively, in some embodiments flowing current between the second terminal and the coil can include (i) flowing a first current between the second terminal and the coil via the first conductive pathway, and (ii) flowing a second current, equal in magnitude to the first current, between the second terminal and the coil via the second conductive pathway. The first current flowing through the first conductive pathway may generate a first electromagnetic field having a substantially equal magnitude to that of a second electromagnetic field generated by the second current flowing through the second conductive pathway.

In some embodiments, current can flow (i) from the second terminal to the junction via the second and third portions (i.e., the first and second conductive pathways, respectively), (ii) from the junction to the first end via the first portion, (iii) from the first end to the second end, and (iv) from the second end to the first terminal via the first conductor. In some embodiments, the current can flow in an opposite direction to that previously described. In such and other embodiments, current (e.g., a first current) can flow between the second terminal and the junction (via the second and third portions) in a first general direction, and current (e.g., a second current) can flow between the junction and the first terminal (via the first portion, voice coil, and first conductor) in a second general direction that is opposite the first general direction. In doing so, the electromagnetic field (e.g., a first electromagnetic field) produced via the first current can cancel (e.g., destructively interfere with) all or at least a portion of the electromagnetic field (e.g., a second electromagnetic field) produced via the second current. Stated differently, the first electromagnetic field effectively can cancel out all or at least a portion of the second electromagnetic field such that no or a limited amount of EMI is produced via the transducer and/or audio device. Operating the transducer and/or audio device in such a manner can result in better sound quality for a listener, and reduce emission of electromagnetic radiation from the transducer and/or audio device. Reducing such emissions can help ensure the corresponding device is below the relevant national, regional and/or international standards electromagnetic radiation. As described elsewhere herein, operating the transducer and/or audio device with the first and second conductive pathways described herein can reduce emission of electromagnetic radiation by at least 5-10 decibels relative to other conventional transducers and audio devices that do not include the first and second conductive pathways.

FIG.6is a flow diagram of a method600of manufacturing a transducer of an audio device configured in accordance with embodiments of the disclosed technology. The method600can include coupling, via a first conductor (e.g., the first conductor325), a first end (e.g., the first end405) of a voice coil (e.g. the voice coil320) to a first terminal (e.g., the first terminal340a) (process portion602), and coupling, via a second conductor (e.g., the second conductor330), a second end (e.g., the second end410) of the voice coil to a second terminal (e.g., the second terminal340b), the second conductor including first and second conductive pathways (e.g., the second and third portions435a-b, respectively) that extend toward the second terminal via opposing sides of the coil (process portion604). In some embodiments, the ends of the voice coil can be coupled to the respective terminals using conductive members such as wires or other suitable conductors. In some embodiments, such conductive members can be molded or formed into other components of the transducer (e.g., molded or formed into a basket or baffle of the transducer).

The above discussions relating to playback devices, controller devices, playback zone configurations, and media content sources provide only some examples of operating environments within which functions and methods described below may be implemented. Other operating environments and/or configurations of media playback systems, playback devices, and network devices not explicitly described herein may also be applicable and suitable for implementation of the functions and methods.

The disclosed technology is illustrated, for example, according to various embodiments described below. Various examples of embodiments of the disclosed technology are described as numbered examples (1, 2, 3, etc.) for convenience. These are provided as examples and do not limit the disclosed technology. It is noted that any of the dependent examples may be combined in any combination, and placed into a respective independent example. The other examples can be presented in a similar manner.

Clause 1: An audio device, comprising: a coil having a first side, a first end disposed on the first side, a second side substantially opposite the first side, and a second end disposed on the second side; a first terminal disposed adjacent the first side of the coil; a second terminal disposed adjacent the first side of the coil; a first conductor extending from the first end of the coil to the first terminal; and a second conductor extending from the second end of the coil to the second terminal, the second conductor including a first conductive pathway and a second conductive pathway spaced apart from the first conductive pathway such that the coil is disposed between the first conductive pathway and the second conductive pathway.

Clause 2: The audio device of any one of the previous clauses, wherein at least a portion of the first conductive pathway is symmetric to the second conductive pathway about an axis extending from the first side through the coil to the second side.

Clause 3: The audio device of any one of the previous clauses, wherein the axis extends through a portion of the first conductor extending from the coil to the first terminal.

Clause 4: The audio device of any one of the previous clauses, wherein the first conductor extends from the coil in a first direction away from the first side and at least a portion of the second conductor extends from the coil in a second direction substantially opposite the first direction.

Clause 5: The audio device of any one of the previous clauses, wherein the first and second conductors are wires.

Clause 6: The audio device of any one of the previous clauses, wherein at least a portion of the second conductor is molded or formed into a basket and/or a baffle of the audio device.

Clause 7: The audio device of any one of the previous clauses, further comprising a filterless amplifier in electrical communication with the first and second terminals.

Clause 8: The audio device of any one of the previous clauses, wherein the first and second conductive pathways are operably configured to carry a substantially equal amount of current.

Clause 9: The audio device of any one of the previous clauses, wherein the first and second conductive pathways are configured to produce a first electromagnetic effect, and wherein the first conductor, the voice coil, and a portion of the second conductor extending from the second end are configured to produce a second electromagnetic effect opposite in polarity to the first electromagnetic effect.

Clause 10: A transducer, comprising: a first terminal; a second terminal; a voice coil including a first end and a second end substantially opposite the first end; a first conductor extending from the voice coil at the first end, the first conductor being electrically coupled to the first terminal; and a second conductor extending from the voice coil at the second end, the second conductor (i) being electrically coupled to the second terminal and (ii) including a first conductive pathway and a second conductive pathway spaced apart from the first conductive pathway, wherein the first and second conductive pathways extend toward the first end via opposing sides of the voice coil.

Clause 11: The transducer of any one of the previous clauses, wherein the first conductive pathway is operably configured to produce a first electromagnetic field, and wherein the second conductive pathway is operably configured to produce a second electromagnetic field substantially equal in magnitude to the first electromagnetic field.

Clause 12: The transducer of any one of the previous clauses, wherein at least a portion of the first conductive pathway is a mirrored reflection of the second conductive pathway about an axis extending from the first end through the voice coil.

Clause 13: The transducer of any one of the previous clauses, wherein at least a portion of the first conductive pathway is a mirrored reflection of the second conductive pathway about an axis extending through the first conductor.

Clause 14: The transducer of any one of the previous clauses, wherein the first and second terminals are proximate one another and positioned along the axis.

Clause 15: The transducer of any one of the previous clauses, wherein the first conductor extends from the voice coil in a first direction toward the first terminal, and wherein at least a portion of the second conductor extends from the voice coil in a second direction opposite the first direction.

Clause 16: The transducer of any one of the previous clauses, wherein the first conductor, second conductor, first conductive pathway, and second conductive pathway comprise wires.

Clause 17: A method of operating an audio device, comprising: providing an audio device comprising a coil, a first terminal, a second terminal adjacent the first terminal, a first conductor extending from a first end of the coil to the first terminal, and a second conductor extending from a second end of the coil to the second terminal; flowing current from the first terminal to the coil via the first conductor; and flowing current from the second terminal to the coil via the second conductor along first and second conductive pathways that extend toward the second terminal via opposing sides of the coil.

Clause 18: The method of any one of the previous clauses, wherein flowing current from the second terminal comprises (i) flowing a first current in a first direction from the second terminal to the coil via the first and second conductive pathways, and (ii) flowing a second current in a second direction between the first terminal and the coil.

Clause 19: The method of any one of the previous clauses, wherein flowing the first current produces a first electromagnetic field having a first polarity, and wherein flowing the second current produces a second electromagnetic field having a second polarity opposite the first polarity.

Clause 20: The method of any one of the previous clauses, wherein the axis extends through a portion of the first conductor extending from the coil to the first terminal.

Clause 21: A method of manufacturing an audio device, comprising: coupling, via a first conductor, a first end of a voice coil to a first terminal; and coupling, via a second conductor, a second end of the voice coil to a second terminal, the second conductor including first and second conductive pathways that extend toward the second terminal via opposing sides of the voice coil.

Clause 22: The method of any one of the previous clauses, wherein the audio device is that of any one of the previous Clauses.

Clause 23: An audio signal processing system of a playback device, the system comprising the audio device or transducer of any one of the previous clauses; a processor; tangible, non-transitory, computer-readable media storing instructions executable by the processor.

Clause 24: A network microphone device comprising one or more microphones configured to detect sound, the audio device or transducer of any one of the previous clauses; one or more processors; tangible, non-transitory, computer-readable media storing instructions executable by the one or more processors.

Clause 25: A playback device comprising a speaker; a processor; and a tangible, non-transitory computer-readable medium storing instructions executable by the processor, the speaker comprising the transducer of any one of the previous clauses.