Blended passive microphone

A blended passive microphone includes a dynamic first microphone, a dynamic second microphone, and a blending circuit adjusting outputs of the dynamic first microphone and the dynamic second microphone.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a microphone used in conjunction with a guitar, instrument or vocal production. More particularly, the invention relates to a blended passive microphone including two microphones, for example, a large dynamic capsule microphone and a smaller dynamic microphone, wherein the outputs of the respective dynamic microphones are adjusted via a dual gang potentiometer.

2. Description of the Related Art

Microphones for use with guitars and other instruments require power and are commonly inconvenient to use. As such, a need exists for a microphone that does not require a power source, that is totally passive, and may be conveniently and reliably used in conjunction with guitars, other instruments and vocal productions.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide a blended passive microphone including a dynamic first microphone, a dynamic second microphone, and a blending circuit adjusting outputs of the dynamic first microphone and the dynamic second microphone.

It is also an object of the present invention to provide a blended passive microphone including a housing member in which components of the blended passive microphone are supported.

It is another object of the present invention to provide a blended passive microphone wherein the dynamic first microphone includes a dynamic microphone cartridge and a first microphone output.

It is a further object of the present invention to provide a blended passive microphone wherein the dynamic second microphone includes a dynamic microphone cartridge and a second microphone output.

It is also an object of the present invention to provide a blended passive microphone wherein the blending circuit includes a dual gang potentiometer.

It is another object of the present invention to provide a blended passive microphone wherein the blending circuit includes an XLR cable output for connection to an audio pro mixer or microphone input on audio accessory equipment.

It is a further object of the present invention to provide a blended passive microphone wherein the XLR cable output is a three-pin XLR cable output.

It is also an object of the present invention to provide a blended passive microphone wherein the blending circuit includes a first input electrically coupled to the POS & NEG outputs of the dynamic first microphone and a second input electrically coupled to the POS & NEG outputs of the dynamic second microphone.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the various figures a blended passive microphone10requiring no voltage is disclosed. The blended passive microphone10is adapted for use in conjunction with guitars, other instruments, and/or vocal productions. The blended passive microphone10of the present invention is constructed to be mounted upon a microphone stand, or may even be handheld, and provides a fully balanced sound signal that is transmitted to an audio mixer or audio accessory equipment via a cable.

The blended passive microphone10of the present invention includes a dynamic first microphone12and a dynamic second microphone14. The dynamic first microphone12is a large dynamic capsule microphone and includes a dynamic microphone cartridge16and a first microphone output18. The dynamic second microphone14is a small dynamic capsule microphone and includes a dynamic microphone cartridge20and a second microphone output22.

The first microphone output18and the second microphone output22are coupled to a blending circuit24. The blending circuit24includes a dual gang potentiometer26that is used to adjust outputs of the dynamic first microphone12and the dynamic second microphone14. The dual gang potentiometer26is adjusted using a knob127(as shown inFIG. 4and as is known to those skilled in the art). The blending circuit24has an XLR cable output28for connection to any audio pro mixer or microphone input on any audio accessory equipment30.

The components of the blended passive microphone10as described above are supported with a housing member100. It is appreciated the housing member100may take a variety of forms without departing from the spirit of the present invention. In accordance with a preferred embodiment, and with reference toFIGS. 4, 5, 6A-D, and7A-E, the housing member100includes a flat front wall102and an arcuate rear wall104. As will be explained below in greater detail, the front wall102includes a solid frame106within which is mounted a perforated grill108allowing for the passage of sound waves therethrough. The housing member100also includes the rear wall104that has a plurality of perforations/slots110allowing for the flow of air necessary to cool the internal components of the blended passive microphone10.

In addition to the perforations/slots110allowing the flow of air, the rear wall104includes a central circular aperture126shaped and dimensioned for the positioning of the control knob127of the dual gang potentiometer26allowing for selective balancing of the present blended passive microphone10. As those skilled in the art will appreciate, the knob127controls the dual gang potentiometer26(in particular, the first and second potentiometers50,52as discussed below) for adjusting the resultant outputs of the dynamic first and second microphones12,14.

The rear wall104is arcuate and includes first and second lateral edges112,114that extend about the perimeter of the rear wall104such that the first and second lateral edges112,114respectively meet the first and second lateral side walls116,118of the front wall102so as to provide for secure attachment thereof in the manufacture of the housing member100. In addition, the housing member100includes a top wall120and a bottom wall122. The top wall120and the bottom wall122complete the enclosure and ensure the formation of a complete housing member100.

In accordance with a preferred embodiment, the top wall120is integrally formed with the front wall102, while the bottom wall122is a separate piece that is attached to the rear wall104during manufacture. The bottom wall122is provided with an aperture124shaped and dimensioned for the passage and/or connection of electrical wires. With this in mind, the top wall120and front wall102may be thought of as forming a front enclosure member128, and the bottom wall122and rear wall104may be thought of as forming a rear enclosure member130. With regard to the front enclosure member128, it should be noted that the frame106and perforated grill108also form the top wall120such that sound coming from either directly in front of the blended passive microphone10or slightly above the blended passive microphone10will freely access the functional components thereof.

While the preferred embodiment discloses a multi-part housing member which is secured together utilizing screws and other attachment mechanisms, it is contemplated the housing member may be formed in a variety of manners without departing from the spirit of the present invention.

In addition to the apertures for the transmission of sound, the front wall includes a central circular aperture shaped and dimensioned for the positioning of a control knob allowing for selective balancing of the present blended passive microphone.

As briefly mentioned above, the dynamic first microphone12of the present blended passive microphone10is a large dynamic microphone (preferably having a cartridge with a diameter of 28 mm or greater) and includes a dynamic microphone cartridge16and a first microphone output18. The first microphone output18is composed of positive (POS) output18aand negative (NEG) output18b. The dynamic first microphone12has a Frequency Response of 50 Hz-14 kHz, a Sensitivity of −52 dB at 1 Volt/Pascal, and an Impedance of 400 ohms. As those skilled in the art will appreciate, a dynamic microphone works based upon the principle of magnetic induction. That is, and in accordance with the present invention, dynamic first microphone12converts acoustic energy in the form of sound waves into an electric signal using a dynamic microphone cartridge16. The dynamic microphone cartridge16includes a diaphragm34attached to a coil36which moves back and forth within a strong magnetic field38. The magnetic field38causes an electric current to flow through the coil36, with a voltage which varies in synchronization with the motion of the diaphragm. The dynamic first microphone12requires no external power or battery to run. However, and as will be appreciated based upon the following disclosure, signals generated by the blended passive microphone10of the present invention are ultimately amplified and processed by audio mixers and other audio processing equipment30that might be used in accordance with the present invention.

The dynamic second microphone14is a small dynamic microphone (preferably having a cartridge with a diameter of 22 mm or less) and includes a dynamic microphone cartridge20and a second microphone output22. The second microphone output22is composed of POS output22aand NEG output22b. The dynamic second microphone14has a Frequency Response of 100 Hz-12 kHz, a Sensitivity of −54 dB at 1 Volt/Pascal, and an Impedance of 600 ohms. As such, and as with the large dynamic first microphone12, the small dynamic second microphone14converts acoustic energy in the form of sound waves into an electric signal using the dynamic microphone cartridge20. The dynamic microphone cartridge20includes a diaphragm40attached to a coil42which moves back and forth within a strong magnetic field44. The magnetic field44causes an electric current to flow through the coil42, with a voltage which varies in synchronization with the motion of the diaphragm40. The small dynamic second microphone14requires no external power or battery to run. However, and as will be appreciated based upon the following disclosure, signals generated by the blended passive microphone10of the present invention are ultimately amplified and processed by audio mixers and other audio processing equipment30that might be used in accordance with the present invention.

The first microphone output18and the second microphone output22are coupled to a blending circuit24. The blending circuit24includes the dual gang potentiometer26that adjusts outputs18,22of the dynamic first microphone12and the dynamic second microphone14.

More particularly, the blending circuit24includes a first input46electrically coupled to the POS & NEG outputs18a,18bof the first microphone output18and a second input48electrically coupled to POS & NEG outputs22a,22bof the second microphone output22. The first and second inputs46,48are electrically connected to the dual gang potentiometer26, which has an XLR cable output28for connection to any audio pro mixer or mic input on any accessory equipment30.

The dual gang potentiometer26includes a first potentiometer50and a second potentiometer52. In accordance with a preferred embodiment, both the first and second potentiometers50,52provide a 10 k taper log and may be adjusted under the control of knob127in a manner well known to those skilled in the art.

The first potentiometer50includes first, second and third pins50a,50b,50c. The first pin50ais connected to ground54, the second pin50bis connected to the POS output18aof the first microphone output18via the first input46of the blending circuit24, and the third pin50cis connected to the XLR cable output28of the blending circuit24(in particular, the third pin28cof the XLR cable output28of the blending circuit24). Similar, second potentiometer52includes first, second and third pins52a,52b,52c. The first pin52ais connected to ground54, the second pin52bis connected to the POS output22aof the second microphone output22via the second input48of the blending circuit24, and the third pin52cis connected to the XLR cable output28(in particular, the third pin28cof the XLR cable output28).

As discussed above, the blending circuit24includes an XLR cable output28adapted for connection to a single three-pin XLR cable56. As is well appreciated, XLR cables are commonly used in conjunction with professional audio equipment, and include first and second connectors58,60having a plurality of pins (in accordance with the present invention a three-pin connection is employed). In fact, three-pin XLR connectors are by far the most common style, and are an industry standard for balanced audio signals.

With this in mind, and as briefly discussed above, the XLR cable output28of the blending circuit24includes a third pin28cthat is connected respectively to the third pins50c,52cof the first and second potentiometers50,52. The first pin28aof the XLR cable output28of the blending circuit24is connected to ground54and the second pin28bof the XLR cable output28of the blending circuit24is connected respectively to the NEG outputs18b,22bof the first and second microphone outputs18,22(via the first and second inputs46,48of the blending circuit24). In this way, XLR cable output28of the blending circuit24provides a blended audio signal that may be used by an audio pro mixer or any audio accessory equipment30. By employing an XLR cable output28, the present blending circuit24provides a balanced signal, that is, the shield of the cable is connected to ground while the audio signals (from the first and second potentiometers50,52as well as directly from the first and second microphone outputs18,22) flow in two conductors which are not connected to ground.