Task 2- Microphones

Microphone

A microphone (which is also nicknamed mic or mike) converts sound to an electrical signal through the sound waves and vibrations.

There are many types of microphones which are used for interviews, live performances, dialogues, group debates, conferences, presentations and audience interaction.

Types 

Handheld

A wireless microphone is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated. A dynamic microphone is also handheld however it is attached by a cable which may be either mono or stereo. A microphone in which the sound waves cause a movable wire or coil to vibrate in a magnetic field and thus induce a current.

Lavalier

A lavalier microphone or lavalier (also known as a lav, lapel mic, clip mic, body mic, collar mic, neck mic or personal mic) is a small microphone used for television, theatre, and public speaking applications in order to allow for hands-free operation.

Direct connect

A DI unit is an electronic device typically used in recording studios and in sound reinforcement systems to connect a high-impedance, line level, unbalanced output signal to a low-impedance, microphone level, balanced input, usually via an XLR connector and cable.

Boundary microphone

A boundary microphone is a small omnidirectional condenser mic capsule positioned near or flush with a boundary (surface). The arrangement provides a directional half-space pickup pattern while delivering a relatively phase-coherent output signal.

Parabolic

A parabolic microphone is a microphone that uses a parabolic reflector to collect and focus sound waves onto a receiver, in much the same way that a parabolic antenna (e.g., satellite dish) does with radio waves.

Noise cancelling

A noise-canceling microphone is a microphone that is designed to filter ambient noise from the desired sound, which is especially useful in noisy environments.

Radio microphones

A wireless microphone is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated.

Construction

Dynamic- Speakers as microphones. A loudspeaker, a transducer that turns an electrical signal into sound waves, is the functional opposite of a microphone. Since a conventional speaker is constructed much like a dynamic microphone (with a diaphragm, coil and magnet), speakers can actually work "in reverse" as microphones.

Condenser- A capacitor has two plates with a voltage between them. In the condenser mic, one of these plates is made of very light material and acts as the diaphragm. The diaphragm vibrates when struck by sound waves, changing the distance between the two plates and therefore changing the capacitance.



Characteristic

 Polar response is a spectrum with omni-directional at one extreme and figure-of-eight at the other. Cardioid and hyper-cardioid are simply convenient way points. To explain these patterns further, fairly obviously an omni-directional mic is equally sensitive all round. The cardioid is most sensitive at the front, but is only 6 dB down in response at an angle of 90 degrees. In fact it is only insensitive right at the back. It is not at all correct, as commonly happens, to call this a unidirectional microphone. The hyper-cardioid is a more tightly focused pattern than the cardioid, at the expense of a slight rear sensitivity, known as a lobe in the response. The figure-of-eight is equally sensitive at front and back, the only difference being that the rear produces an inverted signal, 180 degrees out of phase with the signal from the front.

Proximity effect

The proximity effect in audio is the increased in bass or low frequency response when a when the sound source is too close to the microphone.