Abstract:
A apparatus and method for enabling signals representing a first audio channel and a second audio channel to be conveyed to a first earpiece and a second earpiece, respectively, regardless of which of the first and second earpieces a cable providing both the signals representing the first and second audio channels is coupled to, wherein a first acoustic driver of the first earpiece acoustically outputs the first audio channel and a second acoustic driver of the second earpiece acoustically outputs the second audio channel.

Description:
TECHNICAL FIELD 
     This disclosure relates to personal audio devices worn on or about the head of a user in the vicinity of the ears and coupled via a cable to another device. 
     BACKGROUND 
     It has become commonplace for personal audio devices worn on or about the head of a user in the vicinity of the ears and coupled via a cable to another device to acoustically output stereo audio provided by the other device to the ears such that each ear is provided with distinct left and right audio channels. Examples of such personal audio devices include headphones that may be coupled to another device such as a CD player, an entertainment radio, a television or a MP3 player, and include headsets that may be coupled to another device such as a two-way radio or telephone. 
     However, despite the widespread use of such personal audio devices, users of such personal audio devices often find themselves inconvenienced by the cable that couples such personal audio devices to another device. In essence, users find themselves effectively “tethered” to the other device to which such a personal audio device is coupled such that some degree of flexibility in moving about is lost. Users have often found it necessary to position themselves and/or limit their own movements to avoid putting sufficient tension on the cable to cause the coupling between such a personal audio device and the other device to which it is coupled to be broken, e.g., by pulling apart connectors at one end of the cable. 
     A commonplace solution to this inconvenience has been the use of wireless signaling between such personal audio devices and another device. However, such use of wireless signaling has drawbacks, including the frequent use of batteries with personal audio devices such that use of a personal audio device is limited by the power storage capacity of a battery. Further, issues of electromagnetic interference between devices may arise as a result of using at least some forms of wireless signaling that employ radio frequency transmissions. 
     Another solution to this inconvenience in the case of headsets having a pair of earpieces to acoustically output stereo audio and a communications microphone to enable two-way communications, is to enable the cable to be coupled to either of the earpieces. In this way, a user is provided with at least the flexibility to decide whether they wish to have the cable “tethering” them to another device from either the left side or the right side of the headset. To enable the coupling of the cable to either earpiece, existing known implementations of such headsets have both left and right audio channel conductors, along with a ground conductor, carried by a headband that connects the two earpieces. When the cable is coupled to the left earpiece, right channel audio and ground are conveyed through the headband to the right earpiece. Similarly, when the cable is coupled to the right earpiece, the left channel audio and ground are conveyed through the headband to the left earpiece. 
     Unfortunately, by having both left and right audio channel conductors carried within the headband, left channel audio is conveyed along with right channel audio to the right earpiece when the cable is coupled to the left earpiece, and right channel audio is conveyed along with left channel audio to the left earpiece when the cable is coupled to the right earpiece, despite the fact that the conveying both left and right channel audio from one earpiece to the other in each of these situations is entirely unnecessary. Indeed, in existing known implementations of such headsets, whichever one of the left and right audio channel conductors is rendered unnecessary (depending on which one of the earpieces the cable is coupled to) is also allowed to remain unterminated, thereby causing the unnecessary one of these conductors to act in a manner akin to an antenna, receiving and introducing electromagnetic interference into one or the other of the left and right audio channel. 
     SUMMARY 
     A apparatus and method for enabling signals representing a first audio channel and a second audio channel to be conveyed to a first earpiece and a second earpiece, respectively, regardless of which of the first and second earpieces a cable providing both the signals representing the first and second audio channels is coupled to, wherein a first acoustic driver of the first earpiece acoustically outputs the first audio channel and a second acoustic driver of the second earpiece acoustically outputs the second audio channel. 
     In one aspect, a personal audio device includes a first earpiece having a first acoustic driver to acoustically output a first audio channel and a first connector, a second earpiece having a second acoustic driver to acoustically output a second audio channel and a second connector, a band coupling the first and second earpieces, and a crossover audio conductor carried by the band between the first and second earpieces. The crossover audio conductor is coupled to both the first and second connectors to convey a signal representing the first audio channel from the second earpiece to the first earpiece to be acoustically output by the first acoustic driver at a time when a cable providing signals representing both the first channel audio and the second channel audio is coupled to the second connector; and to convey the signal representing the second audio channel from the first earpiece to the second earpiece to be acoustically output by the second acoustic driver at a time when the cable is coupled to the first connector. 
     Implementations may include, and are not limited to, one or more of the following features. The personal audio device may further include a first audio channel conductor coupling the first acoustic driver to the first connector, a second audio channel conductor coupling the second acoustic driver to the second connector, and a plug that couples the first audio channel conductor to the crossover audio conductor when the plug is coupled to the first connector, and that couples the second audio channel conductor to the crossover audio conductor when the plug is coupled to the second connector. The personal audio device may further include a ground conductor carried by the band between the first and second earpieces, and coupled to both the first and second connectors and both the first and second acoustic drivers. 
     The personal audio device may further include a power conductor carried by the band between the first and second earpieces, and coupled to both the first and second connectors. The personal audio device may further include a first powered circuit coupled to the power and ground conductors, and coupled to the first acoustic driver; a first audio channel conductor coupling the first powered circuit to the first connector; a second powered circuit coupled to the power and ground conductors, and coupled to the second acoustic driver; a second audio channel conductor coupling the second powered circuit to the second connector; and a plug that couples the first audio channel conductor to the crossover audio conductor when the plug is coupled to the first connector, and that couples the second audio channel conductor to the crossover audio conductor when the plug is coupled to the second connector. The first and second powered circuits may provide active noise reduction in at least one of the first earpiece and the second earpiece, may amplify signals representing one or both of the first and second audio channels, and/or may cooperate to provide the personal audio device with wireless communications capabilities. 
     The personal audio device may further include a communications microphone. The communications microphone may be able to be coupled to either one of the first and second connectors. The personal audio device may further include the cable providing the signals representing the first and second audio channels, and the communications microphone may be carried by a portion of the cable, possibly by being carried by an upper coupling of the cable by which the cable is able to be coupled to either one of the first and second connectors. 
     Other features and advantages of the invention will be apparent from the description and claims that follow. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIGS. 1 and 2  depict possible physical configurations of personal audio devices either with or without a communications microphone. 
         FIGS. 3   a  and  3   b  depict a possible electrical architecture of the personal audio devices of either of  FIGS. 1 and 2  in which a signal representing an audio channel for acoustic output is conveyed between earpieces regardless of which one of two connectors a cable providing the signal is coupled to. 
         FIG. 4  depicts another possible electrical architecture of the personal audio devices of either of  FIGS. 1 and 2  in which a signal representing an audio channel for acoustic output is conveyed between earpieces regardless of which one of two connectors a cable providing the signal is coupled to. 
     
    
    
     DETAILED DESCRIPTION 
     What is disclosed and what is claimed herein is intended to be applicable to a wide variety of personal audio devices, i.e., devices that are structured to be used in a manner in which at least a portion of the devices is positioned on or about the head of a user such that earpieces of the devices are positioned in the vicinities of each of the user&#39;s ears, to enable distinct audio channels to be acoustically output to each ear. It should be noted that although various specific embodiments of personal acoustic devices, such as stereo listening headphones and two-way communications headsets are presented with some degree of detail, such presentations of specific embodiments are intended to facilitate understanding through examples, and should not be taken as limiting either the scope of disclosure or the scope of claim coverage. 
     It is intended that what is disclosed and what is claimed herein is applicable to personal audio devices that are at least able to provide distinct audio channels to each ear of a user. It is intended that what is disclosed and what is claimed herein is applicable to personal audio devices that either do or do not provide two-way communications. It is intended that what is disclosed and what is claimed herein is applicable to personal audio devices having physical configurations structured to at least be able to be worn in the vicinity of both ears of a user, including and not limited to, over-the-head headphones, behind-the-neck headphones, headsets with communications microphones (e.g., boom microphones), as well as hats or helmets incorporating earpieces and perhaps a microphone to enable audio communications. Still other implementations of personal audio devices to which what is disclosed and what is claimed herein is applicable will be apparent to those skilled in the art. 
       FIG. 1  depicts an embodiment of a personal audio device  1000   a  having an “over-the-head” physical configuration. The personal audio device  1000   a  incorporates a head assembly  100 , a cable assembly  200  and a plug  300 . The head assembly  100  incorporates an earpiece  110   a  having an acoustic driver  190   a  and a connector  115   a , another earpiece  110   b  having an acoustic driver  190   b  and a connector  115   b , and a headband  120  that couples together the earpieces  110   a  and  110   b . The cable assembly  200  incorporates an electrically conductive cable  220 , an upper coupling  210  to couple one end of the conductive cable  220  to either of the connectors  115   a  and  115   b , a communications microphone  290 , a microphone boom  280  coupling the microphone  290  to the upper coupling  210 , and a lower coupling  230  able to couple the other end of the conductive cable  220  to another device. The plug  300  is able to be coupled to whichever one of the connectors  115   a  and  115   b  is not coupled to the upper coupling  210 . 
     The ability to couple the upper coupling  210  of the cable assembly  200  to either of the earpieces  110   a  and  110   b  (via either of the connectors  115   a  and  115   b , respectively) of the head assembly  100  enables a user of the personal audio device  1000   a  to at least mitigate the inconvenience of being effectively “tethered” to whatever other device to which the personal audio device  1000   a  is coupled through the lower coupling  230  by choosing whether to be tethered from the earpiece  110   a  or the earpiece  110   b . As will be explained in greater detail, multiple electrical conductors  125  (e.g., electrical cabling or other form of electrical conductors) carried by the headband  120  convey electrical signals between the earpieces  110   a  and  110   b , and the plug  300  is coupled to whichever one of the connectors  115   a  and  115   b  is not coupled to the upper coupling  210  to enable the use of both of the acoustic drivers  190   a  and  190   b . With the upper coupling  210  coupled to one of the connectors  115   a  and  115   b , with the plug  300  coupled to the other of the connectors  115   a  and  115   b , and with the lower coupling  230  coupled to another device, electrical signals representing sounds detected by the communications microphone  290  and audio to be acoustically output by the acoustic drivers  190   a  and  190   b  are conveyed between the personal audio device  1000   a  and the other device. 
     To support the ability to couple the upper coupling  210  to either of the connectors  115   a  and  115   b , the position of the communications microphone  290  relative to the upper coupling  210  may be made alterable to enable the communications microphone  290  to be positioned in the vicinity of the mouth of a user, regardless of which of the earpieces  110   a  and  110   b  the upper coupling  210  is coupled to (via one or the other of the connectors  115   a  and  115   b , respectively). In some implementations, the ability to alter the position of the communications microphone  290  relative to the upper coupling  210  may be provided by coupling the microphone boom  280  to the upper coupling  210  in a manner that is hinged and/or rotatable. Additionally and/or alternatively, the microphone boom  280  may itself be structured to be flexible enough to be bent by a user, as for example where the microphone boom  280  has a flexible “gooseneck” structure. Regardless of the exact manner in which the communications microphone  290  is able to be positioned to accommodate coupling the upper coupling  210  to either of the earpieces  110   a  and  110   b  (through one or the other of the connectors  115   a  and  115   b , respectively), the combination of abilities to couple the cable assembly  200  to either of the earpieces  110   a  and  110   b  and to adjust the position of the communications microphone either way can be said to make the personal audio device  1000   a  “reversible” between these two possible conditions. 
     With the provision of the earpieces  110   a  and  110   b  to enable the acoustic output of audio to each of a user&#39;s ears via the acoustic drivers  190   a  and  190   b , respectively, it is possible for the personal audio device  1000   a  to be coupled via the lower coupling  230  to another device capable only of outputting audio to the personal audio device  1000   a  through the coupling  230  for acoustic output to a user. Such another device may be a CD player, a digital music file player, an entertainment radio, or a television, among other possible devices. However, with the further provision of the communications microphone  290 , it is also possible for the personal audio device  1000   a  to be coupled via the lower coupling  230  to another device capable of a two-way exchange of audio through the coupling  230 , thereby enabling a user to engage in a conversation. Such another device may be a two-way radio, a telephone or a vehicular intercom system (e.g., an intercom system on an airplane or armored ground vehicle), among other possible devices. 
     It should be noted that although the depicted embodiment of the personal audio device  1000   a  is of an “over-the-head” physical configuration structured to be worn such that the headband  120  is positioned over the top of a user&#39;s head, other embodiments may replace the headband  120  with another form of band, such as a band structured to be worn around the back of a user&#39;s head and/or around the back of a user&#39;s neck. It should also be noted that although cable assembly  200  is depicted as being a single-piece assembly in which none of the upper coupling  210 , the cable  220 , the lower coupling  230 , the microphone boom  280  and the microphone  290  may be separable from each other, other embodiments of the personal audio device  1000   a  are possible in which one or more of these components are structured to be separable from each other. It should further be noted that although the lower coupling  230  is depicted in a manner suggesting that the lower coupling  230  is a single connector, other embodiments of the personal audio device  1000   a  are possible in which the lower coupling  230  is made up of multiple connectors, possibly conveying electrical signals associated with the acoustic drivers  190   a  and  190   b  separately from signals associated with the communications microphone  290 . It should further still be noted that although the communications microphone  290  is depicted as being coupled to the upper coupling  210  through a microphone boom  280 , other embodiments of the personal audio device  1000   a  are possible in which the communications microphone  290  is disposed more directly on a portion of the upper coupling  210 , and in which perhaps a hollow tube extends from the communications microphone  290  to the vicinity of the mouth of a user to convey speech sounds to the communications microphone  290 . 
       FIG. 2  depicts an embodiment of another personal audio device  1000   b  having an “over-the-head” physical configuration. The personal audio device  1000   b  is substantially similar to the personal audio device  1000   a . However, the personal audio device  1000   b  differs from the personal audio device  1000   a  at least to the extent that the personal audio device  1000   b  lacks both the communications microphone  290  and the microphone boom  280 . In other words, while the personal audio device  1000   a  is structured to enable two-way communications, the personal audio device  1000   b  is structured to enable only acoustic outputting of audio to a user. 
       FIGS. 3   a  and  3   b , taken together, depict an embodiment of an electrical architecture  2000   a  that may be employed by either of the personal audio devices  1000   a  and  1000   b , although without the communications microphone  290  in the case of the personal audio device  1000   b .  FIG. 3   a  depicts in detail the manner in which electrical signals representing sounds detected by the communications microphone  290  (if present) and audio to be acoustically output by the acoustic drivers  190   a  and  190   b  are conveyed with the upper coupling  210  coupled to the connector  115   a  of the earpiece  110   a  and the plug coupled to the connector  115   b  of the earpiece  110   b .  FIG. 3   b  depicts in detail the manner in which those same electrical signals are conveyed when those same couplings are reversed. 
     The cable  220  of the cable assembly  200  conveys multiple signals between the upper coupling  210  and the lower coupling  230  (depicted in  FIGS. 1 and 2 ). The cable  220  incorporates a ground conductor  227  to convey ground between the upper coupling  210  and the lower coupling  230 . The cable  220  also incorporates a L-audio conductor  219   a  to convey a signal representing left channel audio to be acoustically output by the acoustic driver  190   a , and a R-audio conductor  219   b  to convey a signal representing right channel audio to be acoustically output by the acoustic driver  190   b  from the lower coupling  230  to the upper coupling  210 . Where the electrical architecture  2000   a  is employed by the personal audio device  1000   a  such that the communications microphone  290  is present, the cable  220  further incorporates a mic-lo conductor  217  and a mic-hi conductor  218  to convey signals representing sounds detected by the communications microphone  290  from the upper coupling  210  to the lower coupling  230 . The mic-lo conductor  217  and the mic-hi conductor  218  are coupled to the communications microphone  290 , which is carried by the upper coupling  210  as previously discussed, and are not conveyed to any part of the head assembly  100 . 
     The electrical conductors  125  of the head assembly  100  convey multiple signals between the earpieces  110   a  and  110   b . The electrical conductors  125  include a ground conductor  127  to convey ground and a crossover audio conductor  129  to convey an audio signal between the earpieces  110   a  and  110   b . Within the earpiece  110   a , the acoustic driver  190   a  is coupled to the ground conductor  127  and to a L-audio conductor  119   a  to be provided with a signal representing left channel audio to be acoustically output by the acoustic driver  190   a . Further, within the earpiece  110   a , the L-audio conductor  119   a , the ground conductor  127  and the crossover audio conductor  129  are each coupled to separate contacts of the connector  115   a . Similarly, within the earpiece  110   b , the acoustic driver  190   b  is coupled to the ground conductor  127  and to a R-audio conductor  119   b  to be provided with a signal representing right channel audio to be acoustically output by the acoustic driver  190   b . Further, within the earpiece  110   b , the R-audio conductor  119   b , the ground conductor  127  and the crossover audio conductor  129  are each coupled to separate contacts of the connector  115   b.    
     As previously discussed, both of the personal audio devices  1000   a  and  1000   b  are structured to enable the upper coupling  210  to be coupled to either of the connectors  115   a  and  115   b , and to enable the plug  300  to be coupled whichever one of the connectors  115   a  and  115   b  is not coupled to the upper coupling  210 . The connectors  115   a  and  115   b , the upper coupling  210  and the plug  300  are structured to support these various possible couplings among them through the use of electrical contacts of any of a variety of possible physical configurations, including and not limited to, mating electrical contacts disposed directly on exterior portions of casings and/or distinct connectors employing mating tab and socket contacts or mating wiping contacts. 
     With the upper coupling  210  coupled to the connector  115   a  as depicted in  FIG. 3   a , the ground conductor  127  of the conductors  125  is coupled to the ground conductor  227  of the cable  220 , the L-audio conductor  119   a  within the earpiece  110   a  is coupled to the L-audio conductor  219   a  of the cable  220 , and the crossover audio conductor  129  of the conductors  125  is coupled to the R-audio conductor  219   b  of the cable  220 . Further, with the plug  300  coupled to the connector  115   b  as also depicted in  FIG. 3   a , the plug  300  couples the crossover audio conductor  129  to the R-audio conductor  119   b  such that the R-audio conductor  119   b  is coupled through the plug  300  and the crossover audio conductor  129  to the R-audio conductor  219   b.    
     With the upper coupling  210  coupled to the connector  115   b  as depicted in  FIG. 3   b , the ground conductors  127  and  227  are coupled together, the R-audio conductors  119   b  and  219   b  are coupled together, and the crossover audio conductor  129  is coupled to the L-audio conductor  219   a . Further, with the plug  300  coupled to the connector  115   a  as also depicted in  FIG. 3   b , the plug  300  couples the crossover audio conductor  129  to the L-audio conductor  119   a  such that the L-audio conductor  119   a  is coupled through the plug  300  and the crossover audio conductor  129  to the L-audio conductor  219   a.    
     In this way, signals representing left channel audio are always conveyed to the acoustic driver  190   a  of the earpiece  110   a , and signals representing right channel audio are always conveyed to the acoustic driver  190   b  of the earpiece  110   b , regardless of whether the upper coupling  210  is coupled to the connector  115   a  or the connector  115   b , while also minimizing the quantity of conductors that make up the electrical conductors  125  carried by the headband  120  is minimized. As those skilled in the art will readily recognize, minimizing the quantity of conductors carried by a headband is usually deemed desirable for reasons of minimizing the thickness, complexity, expense and weight of a headband, especially where a headband is structured to have an adjustable length between earpieces to accommodate heads of users that are of different shapes and sizes. As those skilled in the art will also recognize, using a single conductor that is selectively coupled in this manner to convey signals representing either left channel audio or right channel audio between the earpieces  110   a  and  110   b  avoids subjecting either of the signals representing the left or right channel audio to the possible introduction of electromagnetic interference. 
       FIG. 4  depicts an embodiment of another electrical architecture  2000   b  that may be employed by either of the personal audio devices  1000   a  and  1000   b , although without the communications microphone  290  in the case of the personal audio device  1000   b . The electrical architecture  2000   b  is substantially similar to the electrical architecture  2000   a . However, the electrical architecture  2000   b  differs from the electrical architecture  2000   a  at least to the extent that a personal audio device adopting the electrical architecture  2000   b  further incorporates powered circuits  180   a  and  180   b  involved in driving the acoustic drivers  190   a  and  190   b , respectively, to acoustically output audio provided by another device to which the lower coupling  230  may be coupled and/or other audio. In some embodiments of the personal audio device  1000   a  or  1000   b  employing the electrical architecture  2000   b , the powered circuits  180   a  and  180   b  may be audio amplifiers, and in other embodiments, the powered circuits  180   a  and  180   b  may be active noise reduction (ANR) circuits. 
     In addition to the conductors previously described as being incorporated into the cable  220 , the cable  220  additionally incorporates a power conductor  228  to convey power from the lower coupling  230  to the upper coupling  210 . In addition to the conductors previously described as being incorporated into the electrical conductors  125 , the electrical conductors  125  additionally include a power conductor  128  to convey power between the earpieces  110   a  and  110   b . Within the earpiece  110   a , the acoustic driver  190   a  is coupled to the powered circuit  180   a , which in turn is coupled to the ground conductor  127 , the L-audio conductor  119   a  and the power conductor  128 . Similarly, within the earpiece  110   b , the acoustic driver  190   b  is coupled to the powered circuit  180   b , which in turn is coupled to the ground conductor  127 , the R-audio conductor  119   b  and the power conductor  128 . Further, the power conductor  128  is coupled to contacts of the connectors  115   a  and  115   b  of the earpieces  110   a  and  110   b , respectively. Regardless of whether the upper coupling  210  is coupled to the connector  115   a  or to the connector  115   b , the power conductor  228  of the cable  220  is coupled to the power conductor  128  of the electrical conductors  125  to convey power to both of the powered circuits  180   a  and  180   b.    
     It should be noted that although the embodiments of personal audio devices and associated electrical architectures depicted and discussed herein largely serve the function of positioning acoustic drivers and perhaps a microphone about portions of a user&#39;s head, other functions may be additionally incorporated. By way of example, either of the personal audio devices  1000   a  or  1000   b  may further incorporate wireless communications capabilities in addition to the wired communications capabilities enabled through the cable assembly  200  such that either of the electrical architectures  2000   a  or  2000   b  may be augmented with a wireless transceiver accompanied by circuitry to switch between and/or combine wired and wireless communications (or perhaps the powered circuits  180   a  and  180   b  may cooperate to provide wireless communications functionality in the electrical architecture  2000   b ). Also by way of example, either of the personal audio devices  1000   a  or  1000   b  may further incorporate ANR capabilities such that one or both of the earpieces  110   a  and  110   b  may further incorporate one or more feedback and/or feedforward microphones and either of the electrical architectures  2000   a  or  2000   b  may be augmented with one or more ANR circuits to cause anti-noise sounds to be acoustically output by the acoustic drivers  190   a  and  190   b  (or perhaps the powered circuit  180   a  provides ANR to the earpiece  110   a , and the powered circuit  180   b  provides ANR to the earpiece  110   b  in the electrical architecture  2000   b ). By way of still another example, either of the personal audio devices  1000   a  or  1000   b  may further incorporate audio playback capabilities such that either of the electrical architectures  2000   a  or  2000   b  may be augmented with a storage device and circuitry to play previously recorded audio stored within the storage device. 
     Other implementations are within the scope of the following claims and other claims to which the applicant may be entitled.