Patent Publication Number: US-11659312-B2

Title: Earphone with solid body

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/532,316, filed on Aug. 5, 2019, which is hereby incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to earphones and methods of their design. Particular embodiments provide solid earphone bodies that include negative spaces for acoustic drivers, sound modifying or transmitting components, or both. 
     BACKGROUND 
     The design and fabrication of electronic devices to be used in small operating environments can be challenging. For example, earphones are required to include drivers and various sound channels in a very small space—particularly for in-ear earphones. Tradeoffs often arise between considerations such as sound quality, durability, and ease of manufacturing. Accordingly, room for improvement exists. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. 
     Described herein are embodiments of an earphone having a solid body, as well as embodiments of methods for designing and fabricating such earphones. 
     In some embodiments, a disclosed earphone includes a solid body. A first mounting recess is formed in a first end of the earphone body. A first acoustic driver is disposed within the first mounting recess. At least one sound bore is formed in the solid earphone body and fluidly communicates with the first mounting recess and a first exit port formed at a second end of the earphone body. The second end of the earphone body is configured to be placed in an ear canal of a user. 
     In a particular embodiment, the solid earphone body can include additional features, such as a sound chamber formed in the solid earphone body and in fluid communication with the at least a first sound bore. 
     In another embodiment, a second mounting recess is formed in the first end of the earphone body. A second acoustic driver is disposed in the second mounting recess. At least a second sound bore is formed in the earphone body and fluidly communicates with the second mounting recess and a second exit port formed at the second end of the earphone body. In another embodiment, the at least a second sound bore communicates with the second mounting recess and the at least a first sound bore. A vent can be formed in the earphone body. When a cap is included, the vent can communicate with a vent formed in the cap. 
     Embodiments of a disclosed earphone can be tubeless. For example, in such embodiments, tubes do not form part of a connection pathway between the first mounting recess and the first exit port. 
     In further embodiments, a disclosed earphone includes a solid earphone body. A mounting recess is formed in a first end of the earphone body. A first acoustic driver is disposed in the mounting recess. A cap covers the mounting recess. 
     In a disclosed method of manufacturing an earphone, a virtual model of at least one physical earphone component and a virtual model of at least a first sound bore are created. A first virtual model of an earphone body is created. The virtual model of the at least one physical earphone component and the virtual model of the at least a first sound bore are positioned at least partially within the virtual model of the earphone body. One or more negative spaces are defined in the virtual model of the earphone body, corresponding to the virtual model of the at least one physical earphone component and the virtual model of the at least a first sound bore. The defining creates a second virtual model of the earphone body. 
     In an embodiment, the method includes creating a solid earphone body using the second virtual model of the earphone body, such as by injection molding or 3D printing. The at least one physical earphone component can be positioned within a recess in the solid earphone body, where the recess corresponds to a portion of the negative space of the second virtual model of the earphone body corresponding to at least a portion of the virtual model of the at least a first earphone component. A cap can be placed over the recess. 
     The manufacturing method, in an embodiment, can include obtaining a representation of a user&#39;s ear. The representation can be converted to at least a portion of the first virtual model of the earphone body. 
     In another embodiment, the virtual model of the at least one physical earphone component can be stored. The stored virtual model of the at least one physical earphone component can be made available for selection during the design of another earphone body. 
     The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 A- 1 F  are cross-sectional views of three-dimensional virtual models of an earphone body, earphone components, and sound modifying or transmitting features that can be included in an earphone, illustrating how such virtual models can be used in creating a model of an earphone body that can be used in manufacturing processes such as 3D printing or injection molding. 
         FIG.  2 A  is a cross-sectional view of an earphone having an earphone body and a cap, where the earphone includes a dynamic driver, a sound bore, and a vent. 
         FIG.  2 B  is a perspective, exploded view of the earphone of  FIG.  2 A , including showing a representation of negative space corresponding to the dynamic driver, sound bore, and vent. 
         FIG.  2 C  is a perspective view of the representation of negative space shown in  FIG.  2 B . 
         FIG.  2 D  is a top plan view of the representation of negative space shown in  FIG.  2 B . 
         FIG.  2 E  is a side view of the earphone body and cap shown in  FIG.  2 B . 
         FIG.  2 F  is a cross-sectional view taken along line C-C of  FIG.  2 E . 
         FIG.  3 A  is a cross-sectional view of an earphone having an earphone body and a cap, where the earphone includes a plurality of balanced armature drivers, a plurality of sound bores, and a plurality of sound chambers. 
         FIG.  3 B  is a perspective, exploded view of the earphone of  FIG.  3 A , including showing a representation of negative space corresponding to the balanced armature drivers, sound bores, and sound chamber. 
         FIG.  3 C  is a perspective view of the representation of negative space shown in  FIG.  3 B . 
         FIG.  3 D  is a top plan view of the representation of negative space shown in  FIG.  3 B . 
         FIG.  3 E  is a side view of the earphone body and cap shown in  FIG.  3 B . 
         FIG.  3 F  is a cross-sectional view taken along line C-C of  FIG.  3 E . 
         FIG.  4    is a cross-sectional view of an earphone having an earphone body and a cap, where the earphone includes a dynamic driver, a plurality of balanced armature drivers, a plurality of sound bores, a plurality of sound chambers, and a vent. 
         FIG.  5    is a flowchart of an example method for manufacturing an earphone having a solid body. 
     
    
    
     DETAILED DESCRIPTION 
     Overview 
     The design and fabrication of electronic devices to be used in small operating environments can be challenging. For example, earphones are required to include drivers and various sound channels in a very small space—particularly for in-ear earphones. Tradeoffs often arise between considerations such as sound quality, durability, and ease of manufacturing. Accordingly, room for improvement exists. 
     For example, earphones typically will include one or more drivers and one more channels for transmitting sound from the drivers to a user&#39;s ear. The channels are often in the form of fixed or flexible plastic tubes. Additional components that can be included in an earphone are electrical connections, such as to deliver power/audio signals to the drivers. Typically, all of these components are included in a shell or housing. In some cases, the housing can be a standardized form factor, and a portion of the earphone to be inserted into the user&#39;s ear (e.g., a “spout”) can include a rubber tip to comfortably secure the earphone in the user&#39;s ear. In other cases, the housing can, at least in part, be custom molded to fit the ear of a particular user. 
     Housings are commonly provided having a plurality of separable portions, such as a portion of the housing that includes a tip to be inserted into the user&#39;s ear, and portion of the housing that will face outwardly, and be maintained within structures of the outer ear such as the tragus, antitragus, concha, and crus helix. During manufacturing, the drivers and other electronic components are typically secured in a cavity formed in a first portion of the housing. Clips or other securing means can be included in the first housing portion in order to secure the drivers or other components in place. A second housing portion can be secured over the open side of the first housing portion, such as using a snap or friction fit, including by inserting a gasket or other sealing means between coapting ends of the first and second housing portions. Other means of securing or sealing the two housing portions can be used, such as using adhesives or by fusing (e.g., thermally) a seam formed at the juncture of the housing portions. 
     While above-described methods of assembling earphones can be acceptable in some cases, such as to mass produce large quantities of standard earphones having acceptable sound quality, they can be problematic. For example, when one or more portions of an earphone housing include relatively larger cavities, the acoustic properties of the earphones can suffer. In addition, clips or other means used to secure drivers and other components within the housing can be prone to breakage, or to having the components slip outside of the clips, particularly if they are adjacent to open space within the cavity. Thus, earphones made using traditional techniques can suffer from durability issues, particularly if dropped or otherwise subjected to impact forces. 
     Similar issues can arise when tubes are used in an earphone. In a particular design, a portion of the housing may have interior passages that lead between an interior portion of the housing and an exterior portion of the housing. For example, a portion of the housing intended to be inserted into a user&#39;s ear canal can have one or more passages that extend from the inside of the housing to the exterior of the housing in order to transmit sound to the user. Tubes, including flexible tubes, may be used to couple the passage to a physical component, such as a driver, located in the cavity of the housing. These tubes can become disconnected or dislodged, which can affect sound quality, and more typically results in the earphones being unusable. 
     The components, and manufacturing techniques, typically used for earphones also can limit the sound reproduction properties of the earphones. For example, as mentioned, a large cavity may have undesirable acoustic properties, and tubes may be used to more precisely transmit sound from sound-generating components of the device to the user&#39;s ear. However, there are typically a limited number of properties of the tubes than can be modified in order to adjust their acoustic properties. Tube properties such as the diameter of the tube, the shape of the ends of the tube (used to attach to other structures of the earphones), and the material from which the tube is constructed may be modified to an extent. However, even potential changes to these properties can be constrained by limitations in the volume of the cavity, space taken by other components, and the length of the tube, and any curvature, needed to couple the different components. Moreover, the length of the tube, apart from perhaps one or both of the ends, typically has a substantially constant diameter, and the ability to bend or shape the tube can be limited. 
     The present disclosure provides an earphone that can address some or all of the problems in prior earphone designs, as well as methods of designing and manufacturing such earphones. One disclosed technology provides an earphone with a solid body that includes one or more negative spaces, or receptacles, for receiving hardware components of the earphone, such as a driver. A negative space for a hardware component can be configured to securely retain the hardware component within an assembled earphone. In some cases, the hardware component can be secured without the need for additional securing elements, such as adhesives or clips. 
     For example, if a hardware component has a plurality of sides, or edges (e.g., for a circle, edges can be considered points connected by a diameter of the circle), the negative space can be configured to receive at least one less than the plurality of sides, with material of the solid body contacting the received sides. At least one side of a hardware component is received by a negative space, and is contacted by surrounding material of the solid body. In further cases, at least two sides of component are received by the negative space, and is contacted by surrounding material of the solid body. Generally, a negative space for receiving a hardware component has an exterior end and an interior end, where the exterior end defines an opening for receiving the hardware component. 
     Another disclosed technology provides an earphone having a solid body defining negative spaces in the form of tunnels or through holes that connect earphone hardware components to an exterior surface of the earphone, such as for transmitting sound to a user. These types of tunnels or through holes are generally referred to herein as sound bores. The tunnels can also be used to interconnect hardware components, or acoustic features of the earphone, including features defined by negative spaces within a solid body of the earphone. 
     The tunnels can include (either integrally or being coupled to) one or more sound chambers, in the form of larger diameter negative spaces that are formed at intermediate sections of the tunnels, or at an end of a tunnel. Tunnels can also be present in the form of vents, such as vents used to adjust pressure in the earphone (including when worn by a user), or to adjust acoustic properties of the earphone. 
     As used herein, tunnels, including sound bores and vents, and sound chambers, are negative spaces with a solid earphone body. Tunnels are distinguished from tubes, where tubes consistent of a lumen defined by tube surface, where the outer surface of the tube is not surrounded by solid material. In particular examples, the disclosed tunnels extend through the body of the earphone and are surrounded by the solid portion of the earphone body for their entire length. However, in some cases, tubes can be inserted through all or a portion of the disclosed tunnels. 
     In a particular implementation, a disclosed earphone includes a generally solid body, defining negative spaces for hardware components, tunnels, or both, and forms a unitary surface. That is, the solid body is free of seams and is constructed as an integral, unitary mass of material. In particular examples, a solid earphone body, when drivers and other physical components have been installed into negative spaces formed in the earphone body, includes less than about 25% of unfilled space (e.g., non-solid material) compared with the total volume of the earphone body, such as less than about 20%, less than about 15%, less than about 10%, or less than about 5% of unfilled space. In particular examples, “about” means within 10% of the recited number. In further examples, an earphone body includes less than 25% of unfilled space, such as less than 20%, less than 15%, less than 10%, or less than 5%. 
     In further examples, a solid earphone body, when drivers and other physical components have been installed into negative spaces formed in the earphone body, is substantially free of unfilled space other than space associated with tuning elements (e.g., sound bores, vents, and sound chambers, or other negative-space features, where tuning elements more generally can include features such as acoustic damper). Substantially free of unfilled space, in this context, can mean less than about 15% of unfilled space compared with the total volume of the earphone body, such as less than about 12%, less than about 10%, less than about 8%, less than about 5%, or less than about 2% of unfilled space. In particular examples, “about” means within 10% of the recited number. In further examples, an earphone body includes less than 15%, 12%, 10%, 8%, 5%, or 2% of unfilled space. 
     The solid body can define an opening that provides access to negative spaces formed in the solid body. After hardware components are inserted into the earphone, a cap or plug can be placed over the opening. In particular implementations, compared with the overall surface area of the earphone body, the opening is less than about 25% of the total surface area, such as less than about 20%, less than about 15%, less than about 10%, or less than about 5% of the total surface area. In particular examples, “about” means within 10% of the recited number. In further examples, the opening is less than 25% of the total surface area of the earphone body, such as less than 20%, less than 15%, less than 10%, or less than 5% of the total surface area. However, in other implementations, the opening can be 20% or more of the total surface area of the earphone body. 
     According to a disclosed method, modeling software can be used to create negative spaces within a three-dimensional representation of a solid earphone body. The negative spaces can include tunnels or through holes, negative spaces for hardware, or a combination thereof, as described above. The solid earphone body can be a standardized body that will be mass produced, or can be a custom body that can adapted for the particular ear shape of an individual end user. Three-dimensional designs produced by modeling negative spaces in a solid earphone body can be fabricated into solid components using techniques such as 3D printing or injection molding. 
     Compared with prior approaches, the innovative disclosed earphones can be faster and easier to manufacture, in that fewer parts (e.g., tubes) may be needed, and installation of hardware components can be facilitated by having custom negative spaces (or voids) for receiving them. Having components secured within negative spaces, and/or fewer components, can make the earphones more robust, such as being better able to withstand both normal handling, and accidents involving sharp impacts, without internal parts becoming dislodged. Further, flexibility in placing internal earphone components, and the shape and position of tunnels, include the fabrication of chambers intermediate or at an end of one or more tunnels, can allow for better earphone performance, and the design of features that can improve sound quality. 
     One or more of these benefits can be achieved with a design process that it is easily adaptable, such as to provide different general earphone designs (e.g., different hardware and/or acoustic channel designs), or to facilitate adapting an earphone design to the ear shape of a particular user. 
     Method of Designing and Fabricating an Earphone with a Solid Body 
       FIGS.  1 A- 1 F  are a series of schematic drawings illustrating components of an earphone according to disclosed embodiments, and how an earphone can be designed and constructed.  FIG.  1 A  illustrates an earphone body  104  having a first end  106 , configured to be inserted into the ear canal  108  of a user&#39;s ear  102 , and a second end  110 , typically configured to be retained in the ear by physical structures of the user&#39;s outer ear. 
     In some cases, the earphone body  104  can be molded from, or otherwise represent, the anatomical features of an individual user&#39;s ear. For example, a mold or impression can be made of the user&#39;s ear, and converted to a three-dimension representation in a software design program, such as AUTODESK INVENTOR or FUSION  360  (both available from Autodesk, Inc., of San Rafael, Calif., and which can be used for the remaining steps associated with  FIGS.  1 A- 1 F ). In other cases, a three-dimensional representation of the user&#39;s ear can be obtained by digitally scanning the user&#39;s ear. In further cases, the earphone body  104  can represent a standardized shape that is designed to satisfactorily fit any user, or at least a majority of users. 
     The first end  106  of the earphone body is typically shaped to securely, but comfortably, fit within the ear canal  108 . In the case of earphone bodies  104  that are not customized, and intended to be used with many different users, the first end  106  can be covered with a tip, typically of rubber or another elastomer, that helps secure the earphone body  104  within the ear, while maintaining user comfort. In addition to helping secure the earphone body  104  in position, a secure fit with the ear canal  108 , either through custom fitting or tips, can help improve the sound quality of the earphone, such as by prevent leakage of sound outside the earphone body, and helping reduce the intrusion of external sounds into the user&#39;s ear. 
     In a similar manner, the second end  110  is typically configured to help secure the earphone body  104  in position by nestling between, or wedging against, natural anatomic structures of the outer ear. Custom molded earphones can include a second end  110  that is also shaped to mate with native ear anatomy of a particular user. Mass produced, or general purpose, earphones can have a second end  110  that is shaped to mate with a variety of ear shapes. 
       FIG.  1 B  illustrates outline representations of various hardware components  114  that can be used in an earphone. The outline representations can be two or three dimensional representations of physical hardware components that will be used in an earphone. In some cases, the outline representations can be obtained by scanning the actual hardware components. In other cases, the outline representations can be manually created, and can approximate the actual shape of the physical components. For example, many hardware components  114  are rectangular, or include rectangular portions, or are circular, or include circular portions, that are easily created using modelling software. 
     The hardware components  114  can include sound drivers (i.e., acoustic drivers), such as balanced armature drivers  116  and a dynamic driver  118 . Hardware components  114  can further include a cable socket  120 , which can be used to deliver electrical signals to the drivers  116 ,  118 , to power the drivers and produce sound to be rendered to a user. 
       FIG.  1 C  illustrates outline representations of sound modifying and transmission structures  122  that can be included in an earphone, and can be represented in design software. The sound modifying structures and transmission structures  122  can include sound bores  124 , acoustic chambers  126 , and vents  128 . Sound bores  124  can transmit sound from the drivers  116 ,  118  to the user&#39;s ear. Vents  128  can be used to allow air movement within the user&#39;s ear, or within the earphone, which can be used to tune the acoustic properties perceived by the user (e.g., to enhance bass). Similarly, acoustic chambers  126  can be used to condition sound to be transmitted to a user, and improve overall audio quality. Note that the acoustic chambers  126  can be a significant advantage of disclosed technologies, as typical methods of earphone production are not capable of incorporating acoustic chambers into an earphone body. 
     The representations of the hardware components  114  and the representations of the sound modifying and transmission structures  122  in modelling software can be used to generate negative spaces. That is, the representations themselves can indicate negative space, or can represent positive structures that are subtracted from a model (such as a model of the earphone body  104 ) in order to create negative spaces in the model. 
       FIG.  1 D  illustrates how the representations of the hardware components  114  and the sound modifying and transmission structures  122  can be arranged to form subassemblies, such as in a modelling software program. As shown, a subassembly  130  is formed by placing the dynamic driver  118  intermediate an acoustic chamber  126   a  and an acoustic chamber  126   b , where the acoustic chamber  126   b  communicates with a sound bore  124   a . Note that the end of the sound chamber  126   b  proximate the dynamic driver  118  has an enlarged opening, like a funnel, in order to capture sound transmitted by the dynamic driver, but tapers to a significantly narrower diameter in adjoining/transitioning into the sound bore  124   a , which then passes though the earphone body  104  towards the first end  106 . 
     A subassembly  132  includes a balanced armature driver  116   a  proximate a sound bore  124   b , while a subassembly  134  include a balanced armature driver  116   b  proximate a sound chamber  126   c , which in turn is proximate an end of a sound bore  124   c . Note that while sound bores  124  and sound chambers  126  are shown as separate components, they can be treated (including being modelled) as unitary components. For example, in a solid body of a physical earphone, a sound bore may have an acoustic chamber at an end, or at an intermediate portion. In a corresponding model from which the physical earphone was created, the combined sound bore/acoustic chamber can be represented as an acoustic chamber overlying a sound bore, or a portion of the sound bore can be manipulated (e.g. stretched, or otherwise having a larger diameter than a remainder of the sound bore) to represent the acoustic chamber. The two modelling approaches can be considered equivalent from the standpoint of the physical solid earphone body. 
     In some cases, the virtual representations of one or more of the hardware components  114 , the sound modifying and transmission structures  122 , or the subassemblies  134  can be stored. For example, a variety of earphone models, either custom or standardized, can be created from different combinations of hardware components  114 . At least many of the sound modifying and transmission structures  122  can also be standardized, or at least substantially standardized. That is, for example, the length and conformation of a particular sound bore  124  can be reasonably consistent between earphone models or custom versions of a specific model, with minor changes to length and/or orientation being made to adapt to changes in the size or shape of the solid earphone body  104  or the particular hardware components  114  being used, and the particular location and orientation thereof. 
       FIG.  1 E  illustrates how the subassemblies  130 ,  132 ,  134  can be incorporated into a virtual model  138  of an earphone body, such as the earphone body  104 . The subassemblies  130 ,  132 ,  134  can be positioned within the model  138  in order to achieve desired acoustic properties, and to accommodate other hardware components of the earphones, such as the cable socket  120 , and other sound modifying or transmitting features (e.g., sound bores, sound chambers, or vents), such as the vent  128 . For example, the sound bores  124  and the vent  128  are positioned such that their ends extend to open at a first end  142  of the virtual model  138 , corresponding to the first end  106  of the earphone body  104 . The hardware components  114 , including the drivers  116 ,  118  are placed towards a second end  144  of the virtual model  138 , corresponding to the second end  110  of the earphone body  104 , where there is a greater interior volume to house the components. The cable socket  120  is also placed at the second end  144  of the virtual model, to allow electrical connection with internal components of the earphone body, such as acoustic drivers. 
       FIG.  1 F  illustrates a cross section of a solid earphone body  150  produced using the virtual model of  FIG.  1 E . The hardware components  114  and sound modifying and transmission structures  122  included in the virtual model  138  are represented as negative spaces  148  in the solid earphone body  150 . 
     In  FIG.  1 F , some of the negative spaces are shown as connecting, which others are shown as disconnected/non-contiguous. For example, the entire negative spaces  148   a - 148   c  for each subassembly  130 ,  132 ,  134  is shown as individually contiguous, but each of those negative spaces is shown as disconnected from the other. At least a portion of the negative spaces  148  may be disconnected, but, in practice, at least a portion of the negative spaces can be connected, but such connection is not shown in the particular cross section of  FIG.  1 F . 
     In some cases, two or more negative spaces in an earphone body can be disconnected. However, it can be beneficial to have the negative spaces for multiple components be connected. In particular, it can be beneficial to have negative spaces  148  corresponding to at least a portion of the hardware component  114  connected, as this can facilitate manufacturing of an earphone, as will be further described. 
     In practice, a user can design an earphone by creating or loading (e.g., selecting saved components from a menu) a virtual model  138  of an earphone, the virtual models of the desired hardware components  114 , and the virtual models of the sound modifying and transmission components  122 , including as incorporated in subassemblies (e.g., subassemblies  130 ,  132 ,  134 ). After the hardware components  114  and sound modifying and transmission components  122  have been appropriately positioned, the components can optionally be converted to negative representations (i.e., if the representations were not already negative representations) such that the volume for these components is subtracted from portion of the virtual model  138  representing solid material, thus defining negative spaces (e.g., negative spaces  148 ) corresponding to the components. An earphone according to the model can then be fabricated, such as by injection molding or 3D printing. 
     However, various modifications can be made to the above-method. For example, an earphone design or manufacturing process can include carrying out one or more, including all, of the steps associated with  FIG.  1 B ,  FIG.  1 C , or  FIG.  1 D . After the virtual models of the relevant hardware components and/or sound modifying or transmission components have been created, including as parts of subassemblies, a virtual model of an earphone body can be created, as described with respect to  FIG.  1 A , and the process can then continue as described with respect to  FIG.  1 E  and  FIG.  1 F . 
     For example, in many cases, it can be beneficial to first design subassemblies of an earphone to achieve desired performance/acoustic properties, including a selection of hardware components and tuning elements. That particular collection of components and tuning elements can then be incorporated into one or more earphone body shapes as desired. In some cases, minor adjustments, such as to the length and conformation of tuning elements, can be made to adapt a particular earphone design to a particular body shape. 
     Example Solid Body Earphones 
       FIGS.  2 - 4    illustrate different earphones designs that can be produced using the technique described in conjunction with  FIGS.  1 A- 1 F . The different earphones designs can represent designs that allow different acoustic properties to be achieved, as well as earphones meeting different price/performance objectives. 
       FIG.  2 A  illustrates a cross-sectional view of an earphone  204  that includes a single dynamic driver  206 . The earphone  204  is formed from a unitary body  208 , onto which a cap  210  can be placed. Both the body  208  and the cap  210  can incorporate negative spaces, both to house hardware components and to allow for sound modification or transmission. The body  208  includes a first end  212  that is configured to be placed in the user&#39;s ear. The body  208  includes a second end  214 , where the second end is completed when the cap  210  is inserted onto the body  208 . 
     The body  208  is constructed from a solid material, such as plastic or metal (or combinations thereof), or from ceramics, including zirconia ceramics. Various negative spaces are formed in the body  208 , including a mounting section  216  configured to receive the dynamic driver  206 . A sound-transmitting end  218  of the dynamic driver  206  can abut a bottom portion of the mounting section  216 , where the mounting section can be in the form of a well having a wider section  220  that abuts the lateral sides  222  of the dynamic driver, and a narrower section  224  that abuts the sound transmitting end  218  of the dynamic driver. 
     The bottom of the mounting section  216  opens into a sound chamber  228  that in turn is connected to a main sound bore  230  that passes through the body  208  to an exit port  284  at the first end  212 . The sound chamber  228  and the main sound bore  230  represent negative spaces in the body  208 , and can be formed during production of the body, such via an injection molding or by 3D printing (including when plastics or ceramics are used for the body  208 ). The body  208  also includes a pressure relief vent  234  that extends from an upper surface  236  of the body to an exit port  286  at the first end  212 . 
     The cap  210  and the body  208  can include mating negative spaces  240 ,  242  for receiving a cable socket  244 . Cables, or other wiring, not shown, can be connected to the cable socket  244 , which in turn is electrically coupled (e.g., via wires) to the dynamic driver  206 . The cap  210  further defines a negative space in the form of a recess  250  for receiving an upper end  252  of the dynamic driver. The upper end  252  of the dynamic driver  206  can have a narrower cross sectional width than the sound transmitting end  218 . The side walls  256  of the recess  250  can be configured to be inserted into a gap between the walls of the mounting section  216  and the lateral sides of the upper end of the dynamic driver  206 . 
     The cap  210  can include a vent bore  260  that extends to a lateral side  262  of the cap, and which can mate withe the pressure relief vent  234 . The vent bore  260  can also extend to, and open into, the recess  250  of the cap  210 . 
     An earphone  204  can be constructed by arranging representations of the dynamic driver  206 , cable socket  244 , sound chamber  228 , main sound bore  230 , and relief vent  234  in a virtual model of the earphone. The representations can be negative space representations, or can be subtracted from a volume of the virtual model of the earphone  204  to create corresponding negative spaces. The cap  210  can be created in a similar manner Once the models of body  208  and the cap  210  have been created, they can be used to create the physical body and cap, such as via 3D printing or injection molding. 
     The dynamic driver  206  can be inserted into the mounting section  216 , and electrically connected to the cable socket  244 . The cap  210  can then be placed over the dynamic driver  206  and the cable socket  244 , such that the sides  256  of the recess  250  are inserted around the upper end  252  of the dynamic driver. The cap  210  can be further secured by using an adhesive (such as a rubberized adhesive), or other fastening means, such as screws. A faceplate  270  can be coupled to the first end  212  of the body  208 . 
       FIG.  2 B  presents an exploded view of the earphone  204 . The body  208  is shown in a generalized fashion (e.g., a cube), as the disclosed technology is not necessarily limited to any particular body shape. The body  208  is shown as including a negative space  280 . The negative space  280  can be represented in a virtual model as negative space  282 . That is, removing negative space  282  from a virtual model of a solid earphone body results in the earphone body  208  having the negative space  280 . As described above, the negative space  282  can include the sound chamber  228 , the sound bore  230 , the vent  234 , the dynamic driver  206 , and at least a portion of the cable socket  244 . Additional views of the negative space  282  are provided in  FIGS.  2 C and  2 D . 
     In  FIG.  2 B , the body  208  is shown with the exit port  284  for the sound bore  230  and the exit port  286  for the vent  234 . The negative space representation  282  shows wells  288  for receiving threaded screw inserts  290 , which can receive screws  292  inserted through openings  294  in the cap  210 . 
     An acoustic damper  296  can be inserted within the vent bore  260  (e.g., the vertical portion that mates with the vent  234 ). An end cap  299 , having an opening  298  to the vent bore  260 , can be placed over the cable socket  244 , and secured to the cap  210 . 
       FIG.  2 E  illustrates a side view of the body  208  and the cap  210 , while  FIG.  2 F  illustrates a cross-sectional view of the body and cap taken along line C-C of  FIG.  2 E . In  FIG.  2 E , the driver  206  is shown within the mounting section  216 . 
       FIG.  3    illustrates an earphone  304  having a plurality of balanced armature drivers  316 ,  318 ,  320  instead of the dynamic driver  206  of  FIG.  2 A . The earphone  304  includes a body  308  and a cap  310 . The body  308  is constructed from a solid material, such as plastic or metal (or combinations thereof), or from ceramics, including zirconia ceramics, and can be formed using methods such as 3D printing (including when the body is made from plastic or ceramic materials) or injection molding. 
     The body  308  defines a plurality of negative spaces, in the form of recessed portions  322 ,  324 ,  326  that are dimensioned to receive and secure first longitudinal ends of the respective balanced armature drivers  316 ,  318 ,  320 . The recessed portions  322 ,  324 ,  326  can result from modeling the first longitudinal ends of the balanced armature drivers  316 ,  318 ,  320  as negative space, or subtracting representations of the balanced armature drivers from a virtual model of the body  308 . 
     The balanced armature drives  316 ,  318 ,  320  are positioned next to (e.g., abutting) sound modification or transmission features formed as negative spaces in the body  308 . In particular, each balanced armature driver  316 ,  318 ,  320  is positioned next to a sound chamber  330  (respectively, to each balanced armature driver, sound chambers  330   a ,  330   b ,  330   c ). The sound chambers  330  can represent a larger diameter space compared with respective sound bores  332 ,  334 ,  336  that extend from lower ends (e.g., towards a first end  338  of the body  308 , which end is configured to be placed in a user&#39;s ear) of the respective sound chamber, through the body  308  to the first end and a respective exit port  340 . The sound chambers  330  can be used, in some cases, to cause resonance in acoustic waves produced by the balanced armature drivers  316 ,  318 ,  320 . For example, sound chamber  330   a  can function as a Helmholtz resonator. 
     Note that the sound bore  334  and the sound bore  336  intersect to end at a common sound bore  342 , having an exit port  340 . Coupling sound bores  334  and  336  can be used to adjust to audio qualities of the earphone  304 , including to adjust resonance properties, in a similar manner as the sound chambers  330 . 
     A faceplate  348  can be placed over the first end  338 , where the faceplate has openings  350  configured to be located over the exit ports  340 . 
     The cap  310  defines a recess  352  that is configured to fit over the second longitudinal ends of the balanced armature drivers  316 ,  318 ,  320 , which extends towards a second end  354  of the body  308 . The cap  310  and the body  308  can include mating negative spaces  356 ,  358  for receiving a cable socket  360 . Cables, or other wiring, not shown, can be connected to the cable socket  360 , which in turn is electrically coupled (e.g., via wires) to the balanced armature drivers  316 ,  318 ,  320 . 
     An earphone  304  can be constructed by arranging representations of the balanced armature drives  316 ,  318 ,  320 , cable socket  360 , sound bores  332 ,  334 ,  336  and sound chambers  330  in a virtual model of the earphone. The representations can be negative space representations, or can be subtracted from a volume of the virtual model of the earphone  304  (e.g., the body  308 , and optionally the cap  310 ) to create corresponding negative spaces. The cap  310  can be created in a similar manner Once the models of body  308  and the cap  310  have been created, they can be used to create the physical body and cap, such as via 3D printing or injection molding. 
     The balanced armature drivers  316 ,  318 ,  320  can be inserted into their respective recesses  322 ,  324 ,  326 , and coupled to the cable socket  360 . The cap  310  can then be placed over the balanced armature drivers  316 ,  318 ,  320  and the cable socket  360 , such that the upper longitudinal ends of the balanced armature drivers are within the recess  352 . The cap  310  can be further secured by using an adhesive, or other fastening means, such as screws. The faceplate  348  can be coupled to the first end  338  of the body  308 . 
       FIG.  3 B  presents an exploded view of the earphone  304 . The body  308  is shown in a generalized fashion (e.g., a cube), as the disclosed technology is not necessarily limited to any particular body shape. The body  308  is shown as including a negative space  370 . The negative space  370  can be represented in a virtual model as negative space  372 . That is, removing negative space  372  from a virtual model of a solid earphone body results in the earphone body  308  having the negative space  370 . As described above, the negative space  372  can include the sound bores  332 ,  334 ,  336 , the sound chambers  330 , the balanced armature drivers  316 ,  318 ,  320 , and at least a portion of the cable socket  360 . Additional views of the negative space  372  are provided in  FIGS.  3 C and  3 D . 
     In  FIG.  3 B , the negative space representation  372  shows wells  376  for receiving threaded screw inserts  378 , which can receive screws  380  inserted through openings  382  in the cap  310 . Acoustic dampers  384  can be inserted in the sound chambers  330   b ,  330   c , as best shown in  FIG.  3 F . An end cap  390  can be placed over the cable socket  360 , and secured to the cap  310 . 
     In general, it is noted that the acoustic properties of a particular earphone can be tuned by incorporating different tuning elements into an earphone body (including different combinations of tuning elements, and tuning elements properties), and by adjusting the properties of the tuning elements (e.g., the length, diameter, and conformation of sound bores and vents, the shape and size of sound chambers). Combinations of tuning elements can include placing acoustic dampers proximate other tuning elements, such as sound bores or vents, including placing acoustic dampers within the path/length of a sound bore or vent. 
       FIG.  3 E  illustrates a side view of the body  308  and cap  310 , while  FIG.  3 F  illustrates a cross-sectional view of the body and cap taken along line C-C of  FIG.  3 E . In  FIG.  3 E , the balanced armature drivers  316 ,  318 ,  320  are shown within their respective recesses  322 ,  324 ,  326 . 
       FIG.  4    illustrates an earphone  402  that includes a dynamic driver  406  and two balanced armature drivers  408 ,  410 . The earphone  402  can be formed from a cap  403  and a body  404 . The body  404  is constructed from a solid material, such as plastic or metal (or combinations thereof), or from ceramics, including zirconia ceramics, and can be formed using methods such as 3D printing (including when the body is made from plastic or ceramic materials) or injection molding. 
     The body  404  can have negative spaces, in the form of recesses  412 ,  414 ,  416 , formed in a second end  417  of the body, for receiving the dynamic driver  406  and the balanced armature drivers  408 ,  410 , respectively, that are accessible through an opening  418  to the body  404 . The recess  412 , for the dynamic driver  406 , can be at least generally similar to the recess  216  of  FIG.  2   . The recesses  414 ,  416 , for the balanced armature drivers  408 ,  410 , can be at least generally similar to the recesses  324 ,  326  of  FIG.  3   . 
     The body  404  can have negative spaces, in the form of recesses  412 ,  414 ,  416 , for receiving the dynamic driver  406  and the balanced armature drivers  408 ,  410 , respectively. The recess  412 , for the dynamic driver  406 , can be at least generally similar to the recess  216  of  FIG.  2   . The recesses  414 ,  416 , for the balanced armature drivers  408 ,  410 , can be at least generally similar to the recesses  324 ,  326  of  FIG.  3   . 
     The recess  412  communicates with a funnel-shaped sound chamber  424 , which in turn communicates with a sound bore  426  that passes through the body  404  to an exit port  428  at a first end  430  of the body. The balanced armature driver  408  communicates with a sound bore  432  that passes through the body  404  to an exit port  434 , while the balanced armature driver  410  communicates with a sound chamber  436  that in turn communicates with a sound bore  438  that passes through the body to an exit port  440 . 
     The cap  403  and the body  404  can include mating negative spaces  446 ,  444  for receiving a cable socket  448 . Cables, or other wiring, not shown, can be connected to the cable socket  448 , which in turn is electrically coupled (e.g., via wires) to the dynamic driver  406  and the balanced armature drivers  408 ,  410 . 
     The cap  403  further defines a negative space in the form of a recess  450  for receiving an upper end of the dynamic driver  406 , in similar manner as described for the cap  210  of  FIG.  2   . The cap  403  can include a vent bore  454  that extends to a lateral side  456  of the cap  403 , and which can mate with a pressure relief vent  458  that is formed in the body  404  and extends through the body from an opening  459  to an exit port  460 . The vent bore  454  can also extend to, and open into, the recess  450  of the cap  403 . 
     An earphone  402  can be constructed by arranging representations of the dynamic driver  406 , balanced armature drivers  408 ,  410 , cable socket  448 , sound bores  426 ,  432 ,  438 , sound chambers  424 ,  436 , and relief vent  458  in a virtual model of the earphone. The representations can be negative space representations, or can be subtracted from a volume of the virtual model of the earphone  402  to create corresponding negative spaces. The cap  403  can be created in a similar manner. Once the models of body  404  and the cap  403  have been created, they can be used to create the physical body and cap, such as via 3D printing or injection molding. 
     The dynamic driver  406  can be inserted into the mounting recess  412 , and electrically connected to the cable socket  448 . The balanced armature drivers  408 ,  410  can be inserted into their respective mounting recesses  414 ,  416  and electrically connected to the cable socket  448 . The cap  403  can then be placed over the dynamic driver  406  and the cable socket  448 , such that the sides of the recess  450  surround the upper end of the dynamic driver. The cap  403  can be further secured by using an adhesive, or other fastening means, such as screws. A faceplate  470  can be coupled to the first end  430  of the body  404 , and can include apertures  472  for communicating with the exit ports  428 ,  434 ,  440 ,  460 . 
     In some implementations, a spout (such as an elongated, optionally tapered structure) configured to be placed into a user&#39;s ear, including when covered by a tip (e.g., a plastic or rubber material), can be used instead of, or in addition to, the faceplate  470 . The spout can be integrally formed at the first end  430  of the earphone body  404 , or can be coupled to the first end (e.g., by snap or friction fit, thermal means, such as welding, or using an adhesive). Although described with respect to the earphone  402 , a spout may also be included in other earphone designs, including the earphone  204  or the earphone  304 . 
     Example Manufacturing Method 
       FIG.  5    presents a flowchart of an example method  500  for manufacturing an earphone. At  510 , a virtual model of at least one physical earphone component is created. The at least one physical earphone component can be, for example, an acoustic driver (such as a balanced armature driver or a dynamic driver), a cable socket, screw mounts/inserts, or acoustic dampers. A virtual model of at least a first sound bore is created at  515 . At  520 , a first virtual model of an earphone body is created, such as from a mold of a user&#39;s ear, from a 3D scan of a user&#39;s ear, from a 3D scan of an earphone body, or by another method. The virtual model of the at least one physical earphone component the virtual model of the at least a first sound bore are positioned, at  525 , at least partially within the first virtual model of the earphone body. At  530 , one or more negative spaces are defined in the first virtual model of the earphone body corresponding to the virtual model of the at least one physical earphone component and the virtual model of the at least a first sound bore to create a second virtual model of the earphone body. 
     The method  500  can optionally include one or more additional steps. For example, at  535 , a solid earphone body can be fabricated from the second virtual model of the earphone body, such by 3D printing or injection molding. A cap, to be placed over at least part of a portion of the earphone body, can be fabricated at  540 , such as by machining, molding, or 3D printing. At  545 , the at least one physical earphone component can be installed in the earphone body, such as in a recess corresponding to a negative space in the virtual model corresponding to the virtual model of the at least one physical earphone component. The cap can be installed on the earphone body at  550 . 
     General Conderations 
     For purposes of this description, certain aspects, advantages, and novel features of the embodiments of this disclosure are described herein. The disclosed methods, apparatuses, and systems should not be construed as limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed embodiments, alone and in various combinations and sub-combinations with one another. The methods, apparatuses, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed embodiments require that any one or more specific advantages be present, or problems be solved. 
     Features, integers, characteristics, compounds, chemical moieties, or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract, and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The present disclosure is not restricted to the details of any foregoing embodiments. The present disclosure extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract, and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. 
     Although the operations of some of the disclosed methods are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed methods can be used in conjunction with other methods. 
     As used herein, the terms “a”, “an” and “at least one” encompass one or more of the specified element. That is, if two of a particular element are present, one of these elements is also present and thus “an” element is present. The terms “a plurality of” and “plural” mean two or more of the specified element. 
     As used herein, the term “and/or” used between the last two of a list of elements means any one or more of the listed elements. For example, the phrase “A, B, and/or C” means “A,” “B,” “C,” “A and B,” “A and C,” “B and C” or “A, B and C.” 
     As used herein, the term “coupled” generally means physically coupled or linked and does not exclude the presence of intermediate elements between the coupled items absent specific contrary language. “Directly coupled” refers to two components that are directly physically coupled or linked, and excludes the presence of intermediate elements. As used herein, the terms “integrally formed” and “unitary construction” refer to a construction that does not include any welds, fasteners, or other means for securing separately formed pieces of material to each other, or features resulting from securing separately formed pieces, such as joints, seams, or discontinuities of shape or material. 
     As used herein, “in fluid communication” means that two components are coupled via a common transmission medium, such as a sound transmission medium (e.g., air). Two components can be referred to as in “direct fluid communication” when a transmission medium can flow directly between the two components, such as without passing through intermediate spaces, such as a tube. 
     In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims.