Austin MullenSacramento Recording Connection


Chapter 5 : Microphones Posted on 2017-07-20 by Austin Mullen

  Summation Of What I Learned :

A microphone is a device that changes accoustic energy into an electric current that can be altered and maipulated.

Microphones are typically the first stop in the signal flow of your recording path.

Any device that converts one form of energy into another form of energy is called a transducer.

 

MICROPHONE SPECIFICATIONS

FREQUENCY RESPONSE : Refers to the difference between what frequencies a performance is actually transmitting, to what the microphone is capturing.

HIGH PASS FILTER : Allows frequencies above a designated point in the frequency spectrum to pass through unaffected, and attenuates or decreases the amplitude of frequencies below that point.

LOW PASS FILTER : Allows frequencies below a designated point in the frequency spectrum to pass through unaffected, and attenuates or decreases the amplitude of frequencies above that point.

POLAR PICK-UP PATTERN

OMNIDIRECTIONAL : This microphone is equally sensitive to sound sources from all directions. Genrally have good to outstanding frequency resoponse.

CARDIOID : This microphone pattern gets it name from the shape of a heart. Is a way of isolating vocals or instruments.More sensitive to the front of the microphone in relationship to the rear. 

- For low frequencies, this is an omnidirectional microphone. 

- This microphone will emphasize the low frequency components of any source that is very close the diaphragm. This is known as the proximity effect. Many singer's use this to add "chest" to light vocal.

- Most cardioid microphones have a built in low pass switch to compensate for this presence.

SUPER CARDIOID  : The rejection of sound from the side is increased, causing the microphone to be more sensitive to the frot source.

HYPER CARDIOID : Designed to reject the sound source from the side even more than the super cardioid. One disadvantage, as it discriminates its side sensitivity, there begins to develop a sensitivity toward the rear of the microphone (180 Degrees).

ULTRA CARDIOID : Designed to greatly increase its front compared with its back sensitivity. Front Pattern still tighter than the hyper cardioid allowing the engineer to focus on a smaller area. 

BIDIRECTIONAL : Equally sensitive from its front to its back. (0 Degrees) to (180 Degrees). Frequency responce is just as good as an omnidirectional microphone.

 

SIGNAL TO NOISE RATIO :

- The measure of the amount of noise to the amount of signal produced by an electronic component. Simply put, the higher the signal to noise rate, the quieter the microphone.

IMPEDANCE : 

- The measure of the resistance of the flow of electricity. To prevent distortion, a mic input impedence is much higher that that of a microphone. 

MAXIMUM SPL :

 - SPL is the measure of the amplitude of a sound. 

DISTORTION : Analog distortion is the result of a voltage exceeding the amount of amplitude by the electronic components in a piece of gear.

 

During the course of this chapter I learned how specific microphones are crucial for specific instances of recording. It all boils down to sensitivity, pick-up pattern, and frequency response. All of this MUST be considered in accordance with the type of instrument or vocal.

 

 

 

 

 

 

 

 

 

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