Related Application Data

[01] This application claims priority to U.S. Patent Application No. 15/235,382 filed on August 12, 2016 which is hereby incorporated herein by reference in its entirety for all purposes.

Field

[02] The present disclosure relates generally to microphones, and more particularly to small microphones that may be configured as, for example, lavalier, lapel, earset, headset, or instrument microphones. These types of microphones can be worn by or attached to the user or instrument and can in certain examples be condenser microphones or electret condenser microphones.

Background

[03] Condenser microphones operate by use of a capacitor, which generally consists of two plates and a voltage between them. One of the plates of the capacitor can be formed of a lighter material, such that it acts as a diaphragm, which vibrates as it encounters sound waves. This changes the distance between the two plates and alters the capacitance. In particular, when the plates are nearer to each other, the capacitance increases inducing a charge current and when the plates are spaced farther apart, the capacitance decreases causing a discharge current. Electret condenser microphones can utilize a ferroelectric material or a permanently electrically charged or polarized material.

[04] Condenser microphones and specifically electret condenser microphones can be used in conjunction with lavalier, lapel, earset, headset, or instrument microphones and other hands-free operation microphones. Lavalier or lapel microphones, sometimes referred to as body microphones, collar microphones, clip microphones, neck microphones or personal microphones, are often used in theatre, musical, television, public speaking, and other environments that require movement of the performer or hands free operation. These types of microphones can be provided with clips to permit attachment to various clothing, e.g., shirts, collars, ties, etc. to allow for a hands-free operation. In certain examples, the cords can be hidden underneath clothing and can be connected directly to a mixer or other recording device or can be connected to a body pack receiver worn on the user, which can transmit a signal to a mixer or other recording device.

Summary

[05] This Summary provides an introduction to some general concepts relating to this disclosure 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 invention.

[06] Aspects of the disclosure herein may relate to a smaller, high fidelity microphone that is easy to conceal. In one example, a microphone can include a cover having a series of slits and a nest. The nest can be configured to receive a first diaphragm, a second diaphragm, and a PCB in a stacked arrangement, such that the PCB is positioned between the first diaphragm and the second diaphragm. In one example, the first diaphragm can define a first plane, the second diaphragm can define a second plane, and the PCB can define a third plane. The first plane, the second plane, and the third plane can extend parallel to one another in the nest. The cover can also include slits having a first length and a second length, and the first length can be greater than the second length. The slits can extend both radially and axially.

Brief Description of the Drawings

[07] The foregoing Summary, as well as the following Detailed Description, will be better understood when considered in conjunction with the accompanying drawings in which like reference numerals refer to the same or similar elements in all of the various views in which that reference number appears.

[08] Fig. 1 shows a perspective view of an example condenser microphone;

[09] Fig. 2 shows an exploded view of an example condenser microphone;

[10] Fig. 2 A shows a front view of an example cover for the condenser microphone of Fig. 1;

[11] Fig. 2B shows a cross-section view of the example cover of Fig. 1A along line A-A of Fig. 2A;

[12] Fig. 2C shows a top view of the example cover of Fig. 2A; [13] Fig. 2D shows a side view of another example cover;

[14] Fig. 2E shows a cross-section view of the cover of 2D along line B-B of Fig. 2D;

[15] Fig. 2F shows a top view of the example cover of Fig. 2C;

[16] Fig. 3A shows a front view of an example nest for a condenser microphone;

[17] Fig. 3B shows a rear view of the example nest of Fig. 3 A.

[18] Fig. 3C shows a top view of the example nest of Fig. 3A.

[19] Fig. 3D shows a side view of the example nest of Fig. 3A.

[20] Fig. 4 shows an example contact spacer for a condenser microphone;

[21] Fig. 5A shows a top view of an example PCB for a condenser microphone;

[22] Fig. 5B shows a side view of the example PCB of Fig. 5A;

[23] Fig. 6 shows a top view of an example spacer for a condenser microphone;

[24] Fig. 7A shows a top view of an example diaphragm for a condenser microphone; and

[25] Fig. 7B shows a side view of the example diaphragm of Fig. 7A.

Detailed Description

[26] In the following description of the various examples and components of this disclosure, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various example structures and environments in which aspects of the disclosure may be practiced. It is to be understood that other structures and environments may be utilized and that structural and functional modifications may be made from the specifically described structures and methods without departing from the scope of the present disclosure.

[27] Also, while the terms "frontside," "backside," "top," "base," "bottom,"

"side," "forward," and "rearward" and the like may be used in this specification to describe various example features and elements, these terms are used herein as a matter of convenience, e.g. , based on the example orientations shown in the figures and/or the orientations in typical use. Nothing in this specification should be construed as requiring a specific three dimensional or spatial orientation of structures in order to fall within the scope of the claims.

[28] Fig. 1 shows an example lapel microphone 100, which in one example can be an electret condenser microphone. The lapel microphone 100 generally includes a cartridge 102 and a cover 104. In one example, the cartridge, when assembled, can have a length that is 9 mm or less and a diameter of 4.5 mm.

[29] Although not shown, the lapel microphone 100 can be provided with a clip that can have elastic properties for securing the lapel microphone to a user's clothing. Although the example herein is shown as a lapel microphone, it is contemplated that the microphone could be configured as an earset or headset microphone and as any other hands- free operation microphone.

[30] Fig. 2 shows an exploded view of the example lapel microphone 100 with the cover 104 removed. A nest or housing 106 can be included within the cartridge 102 for receiving the individual components that are used to convert sound waves into electrical signals as discussed herein. Specifically, the nest 106 can be configured to house a first diaphragm 108a, a second diaphragm 108b, a first washer 110a, a second washer 110b, a first back plate 107a, a second back plate 107b, a contact spacer 112, and a PCB 114. The nest 106 can also include a front washer 148 and a front disk 146.

[31] During operation of the lapel microphone 100, the potential of the back plates

107a, 107b is changed in accordance with the vibration of the diaphragms 108a, 108b. Specifically, sound travels through slits 105a, 105b in the cover and interacts with the diaphragms 108a, 108b causing the diaphragms 108a, 108b to oscillate to cause the capacitance to change between the diaphragms 108a, 108b and the back plates 107a, 107b. The change in the capacitance from the back plate 107a and the diaphragm 108a is then outputted from the back plate 107a to the contact spacer 112, which outputs the potential change to the PCB 114. Also the change in the capacitance from the diaphragm 108b and back plate 107b is outputted directly to the PCB 114. The PCB 114 can be configured to create an output based on the signals received from the contact spacer 112 and the back plate 107b through the cable 138 from the microphone 100. The cartridge 102 can be formed of a cap 102a and a plug 102b. The plug 102b can be configured to fit within the cap 102a to secure the nest 106 within the cartridge 102. [32] The plug 102b can include several radially extending flanges 116a, 116b,

118a, 118b that are configured to align with and engage various slots in the cap 102a and the nest 106. In particular, the plug 102b includes an upper flange 116a and a lower flange 116b that fits within corresponding upper and lower slots in the cap 102a. Also the plug 102b includes a first side flange 118a and a second side flange 118b that are configured to engage a groove or channel 120 located in the nest 106. The channel 120 of the nest 106 may also include cutouts 121 that are configured to receive projections 124 located on the first side flange 118a and the second side flange 118b. In this way, the projections 124 act as detents that are received in the cutouts 121 to form a snap-fit type connection. The radially extending flanges 116a, 116b, 118a, 118b can also shield the rear portion of the nest 106. In one example, the plug is formed of a suitable metal material and the nest is formed of a polymer material such that the flanges 116a, 116b, 118a, 118b shield the polymeric material of the nest 106. The radially extending flanges 116a, 116b, 118a, 118b also help to reduce the number of components needed to form the cartridge in that there does not need to be an additional component to interface between the plug 102b and the nest 106.

[33] The plug 102b may also include surface flanges 128 that are configured to be received into corresponding surface openings 130 located in the cap 102a, and the cap 102a and the plug can be welded together to assemble the microphone. However, in other examples the cap 102a and the plug 102b can form a snap-fit or friction-fit to secure the cap 102a and the plug 102b.

[34] The cap 102a can include an upper flat surface 126a and a lower flat surface

(not shown). The volume between the cover 104 and upper flat surface 126a and the volume between the lower surface and the cover can be sized to optimize the acoustic properties of the microphone. The upper flat surface 126a and the lower flat surface can include a series of holes 122 to internally open the cap 102a to the first diaphragm 108a and the second diaphragm 108b. The holes 122 are, thus, configured to receive sound waves, which interact with the first diaphragm 108a and the second diaphragm 108b.

[35] As shown in Figs. 1, 2A-2C, the cover 104 can be formed of a cylindrical- hemispherical shape, where an end is formed of a hemispherical shape. The cover 104 generally forms a volume of air, which can be referred to as a tube. The cover 104 generally includes a series of slits 105a, 105b configured as acoustic openings that extend axially and radially along the cover 104 thereby controlling the volume of air within the tube. The slits 105a, 105b can be configured such that sound waves can travel through the cover 104 and into the microphone 100 to vibrate the diaphragms 108a, 108b.

[36] In one example, the slits 105a, 105b can alternate in axial and radial length along the cover. The length of the slits 105a, 105b changes the acoustic properties of the microphone by determining how many holes in the underlying cartridge 102 are exposed and controlling the volume of air that is exposed. In particular, the slits 105a can extend to a first axial and radial length that is longer than a second axial and radial length of the slits 105b. In addition the slits 105a, 105b can curve inward toward the top of the cover in the axial and radial direction. It is also contemplated that the series of slits 105a, 105b can extend to the same axial and radial length and the axial and radial lengths of the slits can be adjusted according to the desired acoustic properties of the microphone.

[37] The cover 104 may also include a cylindrical rim 103 that is configured to engage the cap 102a. In this example, the cylindrical rim 103 can be maintained on the cap 102a by way of a friction or interference fit. Additionally, the cover 104 can be provided with a series of projections 109, which extend radially inward, to allow the cover 104 to frictionally engage the cap 102a to secure the cover 104 to the cap 102a. In this way, the cover 104 can be held onto the cap 102a during use and may also be removed to use a different cover, such as cover 204 discussed below.

[38] The slits 105a, 105b can define a slit area, and the cylindrical rim 103 can define a cylindrical rim area. In one example, the cylindrical rim area can longer in the axial direction than the cylindrical rim area. In one example, the cover 104 can be molded by a suitable injection molding process from a polymeric material, such as an injection molding grade of acrylonitrile butadiene styrene ("ABS"), for example, ABS-LUSTRAN® 348 and other like materials. However, in other examples, the cover 104 can be formed of a metal or various metal alloys.

[39] Figs. 2D-2F show another exemplary cover 204, in which like reference numerals refer to the same or similar elements as cover 104 discussed above. The cover 204 may also be formed of a cylindrical-hemispherical shape, where an end is formed of a hemispherical shape. However, the slits 205a, 205b can be shorter than the slits 105a, 105b to provide varying acoustic properties. Also, the cylindrical rim 203 can be formed larger in the axial direction than the cylindrical rim 103 for engaging the cap 102a. Also, the slit area can be formed of a similar axial length as the axial length of cylindrical rim area.

[40] Like in the above example, the cover 204 generally forms a volume of air or a tube. The slits 205a, 205b can also be configured as acoustic openings that extend axially and radially along the cover 204 thereby controlling the volume of air within the tube and can be configured such that sound waves can travel through the cover 204 and into the microphone 100 to vibrate the diaphragms 108 a, 108b.

[41] In one example, the frequency response with cap 204 can have a more high end response than cap 104. In this example, the high frequencies can be accentuated in cap 204 relative to the cap 104. Also the cap 104 can have a flatter frequency response relative to cap 204. Moreover, the cap 204 can boost the high frequencies relative to the cap 104. In this way both covers 104, 204 can be provided in a microphone kit with the cartridge 102, such that the user can select the most suitable cover for the particular application. It is also contemplated that instead of covers 104, 204 a simple sleeve could be used for covering the cartridge. The sleeve can be a mesh or foam sleeve. The alternative sleeve or sleeves could also be provided in the microphone kit.

[42] Also in this example, the slits 205a, 205b can alternate in axial and radial length along the cover. The length of the slits 205a, 205b changes the acoustic properties of the microphone by determining how many holes in the underlying cartridge 102 are exposed and controlling the volume of air that is exposed. Again, it is also contemplated that the series of slits can extend to the same axial and radial length, and the axial and radial lengths of the slits can be adjusted according to the desired acoustic properties of the microphone. The cover 204 may also be molded by a suitable injection molding process from a polymeric material as discussed above.

[43] The nest 106 is shown in Figs. 2 and 3A-3D. As shown in Fig. 2, the nest

106 can be generally sized to fit within the cartridge 102. As shown in Fig. 3C, which is a top view of the nest 106, the nest 106 can have a curved front end and a flat back end. The curved profile can accommodate the curved profile of the cap 102a and cover 104. The flat back end can be configured to accommodate the plug 102B of the capsule 102 such that the nest 106 can be secured within the plug 102b. [44] As shown in Figs. 3A and 3B, the nest 106 can include a tapered upper portion 140a and a tapered lower portion 140b to conform with the cartridge 102. The tapered upper portion 140a and the tapered lower portion 140b allow the nest to conform with the curvature and shape of the capsule 102 and the cover 104. The area between the tapered upper portion 140a and the tapered lower portion 140b creates a channel 120 that is configured to receive the side flanges 118b, 118a of the plug 102b. In one example, the nest 106 can be formed of a liquid crystal polymer, or a glass reinforced liquid crystal polymer. However, other suitable comparable materials are also contemplated.

[45] The nest 106 is a generally hollow structure having an opening 132 that extends through the body of the nest 106. The opening 132 of the nest 106 is configured to receive the internal components of the microphone 100, including the first diaphragm 108a, the second diaphragm 108b, the first washer 110a, the second washer 110b, the first back plate 107a, the second back plate 107b, the contact spacer 112, and the PCB 114. Also, the first diaphragm 108a, the second diaphragm 108b, the first washer 110a, the second washer 110b, the first back plate 107a, the second back plate 107b, the contact spacer 112, and the PCB 114 are arranged in a parallel arrangement in that each define a plane, and each of the planes are configured to extend parallel to one another. Additionally, each of the axes of the first diaphragm 108a, the second diaphragm 108b, the first washer 110a, the second washer 110b, the first back plate 107a, the second back plate 107b, the contact spacer 112, and the PCB 114 extend parallel to the axis of the nest.

[46] In addition, the first diaphragm 108a, the second diaphragm 108b, the first washer 110a, the second washer 110b, the first back plate 107a, the second back plate 107b, the contact spacer 112, and the PCB 114 are arranged in a stacked arrangement relative to and within the nest 106. The stacked arrangement allows for a more compact assembly of the microphone 100. The stacked arrangement can be accomplished by positioning the PCB 114 between the contact spacer 112, the first diaphragm 108a, the second diaphragm 108b, the first washer 110a, the second washer 110b, the first back plate 107a, and the second back plate 107b. Also the contact spacer 112 is configured to be placed into direct electrical contact with the first back plate 107a, and the second back plate 107b can be placed into direct electrical contact with the PCB 114. With this arrangement, the contact spacer 112 can be configured to transfer the change in capacitance from the back plate 107a and transfer the capacitance change to the PCB 114, and the back plate 107b can transfer the capacitance change directly to the PCB 114, which then transfers the signal to the cable 138, thereby outputting an electrical signal from the microphone.

[47] As discussed herein, the nest 106 can be provided with a series of projections, slots, notches, cutouts, or holes for receiving the various components of the microphone 100. The opening 132 of the nest 106 can be provided with four notches 134 in each corner sidewall that are configured to receive four corresponding tabs 113 of the contact spacer 112. Notches 134 can also receive the tabs 115a of the first back plate 107a such that the first back plate 107a is placed directly on top of the contact spacer 112 and the flange 152 extends into electrical contact with the PCB 114 and the second back plate 107b. Likewise, four additional notches (not shown) are provided in the bottom of the opening of the nest 106 to receive the second back plate tabs 115b. The opening 132 of the nest 106 can also be provided with a series of ledges 136 for receiving the washers 110a, 110b and the diaphragms 108a, 108b. In one example, the diaphragms 108a, 108b can be adhered to the nest 106 and the washers 110a, 110b are held in position against their respective back plates 107a, 107b by their respective diaphragms 108a, 108b.

[48] As shown in Fig. 3A, which is a front view of the nest 106, the nest 106 can be provided with a front circular opening 142, which provides for barometric pressure relief, and a chamfered shoulder 150 for receiving the washer 148 and the disk 146. The disk 146 can be formed as a circular plate and can include a small hole at its center for relief of barometric pressure through the front circular opening 142. In other examples, however, the disk 146 can include several holes or can be formed as a screen. Also as shown in Fig. 3B, which is rear view of the nest 106, a rear slot 144 is provided for receiving the PCB 114, such that the PCB is configured to extend from the rear of the nest 106. In this way, a rear portion of the PCB can be electrically coupled with the cable 138 to transmit a signal through the cable.

[49] Fig. 4 shows a bottom perspective view of the contact spacer 112. The contact spacer can include several tabs 113 for positioning the contact spacer 112 into the nest 106, such that the contact spacer has an appearance of a "dog-bone" shape. The contact spacer 112 can also include a flange 152 extending at a 90° angle with respect to the body of the contact spacer. The flange 152 connects the PCB 114 and the first back plate 107a to form an electrical connection between the first back plate 107a and the PCB 114. In one example, the flange 152 can be electrically connected to the PCB by way of a conductive epoxy, solder, weld, or like connection. However, the second back plate 107b can be directly coupled to the PCB with a conductive epoxy, solder, or weld. The contact spacer 112 can be formed of stainless steel and, in one particular example, the contact spacer 112 can be formed of annealed 316 stainless steel at 0.10 in. thick. In one example, the contact spacer 112 can be formed in a chemical etching process, and an additional tab 117 is provided as part of the formation process.

[50] Additionally, the shape of the contact spacer can be altered to provide differing acoustic properties, for example, rectangular, circular, ovoid, trapezoidal, triangular, and the like, can be used to change the acoustic properties of the microphone. Therefore, it is contemplated that the nest 106 can be manufactured with different contact spacers in order to alter the acoustic properties of the microphone. The next 106 may also be configured to be universal in order to accept different shaped contact spacers to provide different acoustic properties.

[51] As shown in Fig. 5, which is a top view of the PCB 114, the PCB 114 can include ten sides to form a decagon. The PCB 114 can be configured to convert the very high electrical impedance of the cartridge to a lower impedance suitable for passing a signal through the cable, attenuate the signal where required, and to filter RF interference. The shape of the PCB 114 can be configured such that it can fit in the assembly while also providing enough area for all of its various components. Therefore, other shapes and configurations of the PCB 114 are also contemplated depending on the desired arrangement.

[52] Fig. 6 shows a top view of the back plate 107a. The back plate 107a can be provided with a series of back plate tabs 115a for aligning the back plate 107a with the nest 106. In one example, the back plate 107a can include an electret material such that the back plate 107a is permanently electrically charged to create an electromotive force. For example, the back plate 107a can be formed entirely of the electret material or the electret material can be laminated on a surface that faces the diaphragm 108 a. In one example, the electret material can be a fluorine resin such as, polytetrafluoroethylene (PTFE) or Teflon®. However, it is also contemplated that a film electret can be adhered to the diaphragm to generate the electromotive force, and the back plate 107a can be formed of a simple metal and can be arranged such that it faces the diaphragm.

[53] Back plate 107b can be formed identically to back plate 107a. The back plates 107a, 107b can be aligned with the diaphragms and spaced apart from the diaphragms by the washers 110a, 110b to create two parallel capacitors. Also as discussed herein, the back plates 107a, 107b can be placed into a parallel arrangement to each other such that they are parallel to the axis of the body of the microphone 100 and the axes of the diaphragms 108a, 108b.

[54] A top view of the exemplary diaphragm is shown in Fig. 7A, and a side view of the exemplary diaphragm of Fig. 7A is shown in Fig. 7B. The diaphragm 108b can be formed identically to the diaphragm 108a. As shown in Figs. 7A and 7B, the diaphragm 108a includes a diaphragm body 154 and a diaphragm support 156. The diaphragm body 154 can be provided with two sound penetration holes 158 for receiving sound waves from the slits 105a, 105b in the cover 104. The diaphragm support can be gold plated or plated with any suitable material for providing a suitable capacitor. In one example, the diaphragm body 154 is bonded to the diaphragm support 156 by an adhesive. However, in other examples the diaphragm body 154 and the diaphragm support 156 can be integrally molded together in an injection molding operation, for example.

[55] In one example, the diaphragms 108a, 108b can be formed into an elongated oval shape or elliptical shape. As discussed above, the diaphragms 108a, 108b are also placed into a parallel arrangement to each other such that they are parallel to the axis of the body of the microphone 100. Accordingly, the diaphragms 108a, 108b extend axially along a majority of the body of the microphone. Also the elongated profile of the elliptical diaphragms 108a, 108b helps to maximize the electrostatic capacity in comparison to a circular shaped diaphragm. However, other shapes of the diaphragms are also contemplated, such as square, rectangular, circular, and the like.

[56] The example microphone discussed herein employs a dual diaphragm structure where two diaphragms 108a, 108b are used. The inclusion of two diaphragms 108a, 108b doubles the area and electrostatic capacity thereby increasing the effectiveness of the microphone within a limited space. Also, the diaphragms 108a, 108b can be positioned such that they oscillate in an opposite phase from one another to assist in canceling mechanical pickup noise such as noise caused by the user inadvertently rubbing the cable. In particular, when the microphone encounters mechanical noise, the microphone is configured to mechanically cancel noises by obtaining a summation signal of the diaphragms vibrating in an opposite phase. This helps to maintain the noise amplified in the microphone at a lower level.

[57] Also the diaphragm body 154 can be set at a particular resonant frequency depending on the desired application of the microphone. In one example, the resonant frequency of the diaphragm 108a can be set to 30 to 34 kHz. However, it is contemplated that the diaphragm body 154 can bet set at other resonant frequencies ranging from 20 to 40 kHz.

[58] The washers 110a, 110b can generally follow the perimeter shape of the diaphragm support 156. The washers 110a, 110b can be placed between the back plates 107a, 107b and their respective diaphragms 108a, 108b. The washers 110a, 110b, thus, create a spacing between the back plates 107a, 107b and the diaphragms to form two capacitors. In certain examples, the washers can be formed of various materials, which include, PTFE, PEEK, Polyimide, ETFE and other like materials. It is also contemplated that insulators can be used and that one or more adhesives could be used to replace the washers entirely. Specifically, an adhesive could be applied to either the diaphragms 108a, 108b or the back plates 107a, 107b to provide the desired spacing between the diaphragms 108a, 108b and the back plates 107a, 107b.

[59] To assemble the microphone 100, the PCB 114 can be placed into the opening of the nest 106 and is secured by an adhesive such that it extends through rear slot 144. The contact spacer 112 is then placed into the opening 132, and the tabs 113 are aligned with and adhered within the notches 134. The back plates 107a, 107b are then also placed into the opening 132 and their respective tabs are adhered to the notches 134. The washers 110a, 110b are then adhered to the ledges in the opening 132. Next, the diaphragms are placed over the washers 110a, 110b and can also be adhered into place on the nest 106. The washer 148 and disk 146 are then placed into the chamfered shoulder of the nest 106 and are secured by a suitable adhesive. In one example, a UV-curable adhesive can be used for securing the various components to the nest 106. [60] At this point, the assembled nest 106 can then be placed into the plug 102b by aligning the side flanges 118a, 118b with the channel 120 of the nest 106 and the upper and lower flanges 116a, 116b with the top and bottom of the nest 106. A rear portion of the PCB can be electrically coupled with the cable 138. The plug 102b and nest 106 can then be placed into the cap 102a, and the plug 102b can be secured to the cap 102a by suitable welding methods.

[61] In one example, a microphone can include a cover having a series of slits, a cartridge, and a nest configured to be placed within the cartridge. The nest can be configured to receive a first diaphragm, a second diaphragm, and a PCB in a stacked arrangement, such that the PCB is positioned between the first diaphragm and the second diaphragm. The first diaphragm can define a first plane, the second diaphragm can define a second plane, and the PCB can define a third plane. The first plane, the second plane, and the third plane can extend parallel to one another. The cover can include a hemispherical end, and the slits of the cover can have a first length and a second length, and the first length can be greater than the second length. Also the slits can extend both radially and axially. In one example, the microphone can be configured to be secured to a user's clothing

[62] The nest can be configured to receive a first washer, a second washer, a first back plate, a second back plate, and a contact spacer. The contact spacer can be placed into direct electrical contact with the first back plate and the PCB and the second back plate is placed into direct electrical contact with the PCB. The nest may also include a first ledge for receiving the first diaphragm and a second ledge for receiving the second diaphragm. The first ledge and the second ledge can include notches for receiving tabs of a first back plate and a second back plate. The cartridge comprises a cap and the cap comprises a series of holes configured to receive sound. In one example, the microphone is an electret condenser microphone.

[63] In another example, a microphone can include a cover having a cylindrical shape and a hemispherical end, and the microphone can be an electret condenser. The microphone can also include a cartridge configured to receive the cover. A nest can be configured to be placed within the cartridge, and the nest can be configured to receive a first diaphragm, a second diaphragm, and a PCB in a stacked arrangement, such that the PCB is positioned between the first diaphragm and the second diaphragm. The first diaphragm can define a first plane, the second diaphragm can define a second plane, and the PCB can define a third plane. The first plane, the second plane, and the third plane can extend parallel to one another.

[64] The cover may include a series of slits, the slits having a first length and a second length, and the first length can be greater than the second length. The slits can extend both radially and axially and alternate between the first length and the second length. The slits can also curve radially inward.

[65] The nest can be further configured to receive a first washer, a second washer, a first back plate, a second back plate, and a contact spacer. The contact spacer can be placed into direct electrical contact with the first back plate and the PCB, and the second back plate can be placed into direct electrical contact with the PCB. The nest can include a first ledge for receiving the first diaphragm and a second ledge for receiving the second diaphragm. The first ledge and the second ledge can include notches for receiving tabs of a first back plate and a second back plate. The nest can include a channel for receiving the cartridge.

[66] In another example, a microphone cover can include a cylindrical shape and a hemispherical end, a series of slits. In one example, the slits can have a first length and a second length, the first length being greater than the second length. The slits can extend both radially and axially and can curve radially inward. The slits can alternate between the first length and the second length. The cover can be configured to receive a microphone cartridge of a lapel microphone. The cover can be formed of a polymeric material, and the polymeric material can be an injection molding grade of acrylonitrile butadiene styrene. The cover may also be formed of a metal or a metal alloy. The cover may also include a cylindrical rim configured to receive a microphone cartridge. The cover can also include a slit area and a cylindrical rim area, and the slit area can be longer in the axial direction than the cylindrical rim area. The cover can include a slit area and a cylindrical rim area, and the cylindrical rim area can be of a similar length in the axial direction as the cylindrical rim area in the axial direction.

[67] In another example, a method of forming a microphone can include providing a nest configured to receive a first diaphragm, a second diaphragm, and a PCB in a stacked arrangement, positioning a PCB between the first diaphragm and the second diaphragm. The first diaphragm may define a first plane, the second diaphragm may define a second plane, and the PCB may define a third plane and the method can include arranging the first diaphragm and the second diaphragm, and the PCB such that the first plane, the second plane, and the third plane extend parallel to one another. The method may also include providing a cover having a cylindrical shape and a hemispherical end and forming the cover with a series of slits, and in one example, the slits can have a first length and a second length. The method may include forming the first length greater than the second length, arranging the slits both radially and axially and alternating the slits between the first length and the second length, placing a first washer, a second washer, a first back plate, a second back plate, and a contact spacer into the nest, placing the contact spacer into direct electrical contact with the first back plate and the PCB, placing the second back plate into direct electrical contact with the PCB.

[68] In another example, a microphone kit can include a cartridge, a first cover and a second cover. Both the first cover and the second cover can include a cylindrical shape and a hemispherical end and a series of slits. The slits can extend both radially and axially and can curve radially inward. The first cover and the second cover can be configured to receive the microphone cartridge. The kit may further include a nest configured to be placed within the cartridge. The nest may include a first diaphragm, a second diaphragm, and a PCB placed in a stacked arrangement, such that the PCB is positioned between the first diaphragm and the second diaphragm. The first diaphragm may define a first plane, the second diaphragm may define a second plane, and the PCB may define a third plane, and the first plane, the second plane, and the third plane may extend parallel to one another. The first cover and the second cover series of slits can have a first length and a second length, and the first length can be greater than the second length. In addition, the length of the cartridge can be 9 mm or less.

[69] The present invention is disclosed above and in the accompanying drawings with reference to a variety of examples. The purpose served by the disclosure, however, is to provide examples of the various features and concepts related to the invention, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the examples described above without departing from the scope of the present invention.