MicrophonesMicrophones

The microphone is your primary tool in the sound chain from sound

source to audio storage medium.

Factors when capturing a sound Factors when capturing a sound with a microphone:with a microphone:

microphones location in relation to the microphones location in relation to the sound sourcesound source

the acoustic environment in which we the acoustic environment in which we choose to record the sound source choose to record the sound source

Types of MicrophonesTypes of Microphones

There are There are three three main types of main types of microphones:microphones:

1) Dynamic/Moving Coil1) Dynamic/Moving Coil

2) Ribbon2) Ribbon

3) Condenser/Capacitor3) Condenser/Capacitor

1) Dynamic/Moving Coil 1) Dynamic/Moving Coil microphonesmicrophones

Example: Shure SM 57Example: Shure SM 57

They operate on a They operate on a magnetic principle : magnetic principle : movement of a copper movement of a copper coil around a magnet coil around a magnet causes a changing flow of causes a changing flow of electrons that represent electrons that represent the sound wavethe sound wave

Dynamic/Moving Coil microphonesDynamic/Moving Coil microphonesAdvantages:Advantages:

durable and can withstand a lot of volume. durable and can withstand a lot of volume.

colours the sound in range between colours the sound in range between 5-10khz, this adds clarity, presence and 5-10khz, this adds clarity, presence and understandability to many vocal and understandability to many vocal and instrument sounds.instrument sounds.

doesn’t feedback as easily as other micsdoesn’t feedback as easily as other mics

Dynamic/Moving Coil microphones Dynamic/Moving Coil microphones typical uses:typical uses:

mostly live situations, but they are also mostly live situations, but they are also used a lot in the studio.used a lot in the studio.

close mic applications (1-12 inches)close mic applications (1-12 inches)

drums, guitar, vocals and any instrument drums, guitar, vocals and any instrument that can play loud.that can play loud.

Dynamic/Moving Coil microphones Dynamic/Moving Coil microphones disadvantage:disadvantage:

These microphones often miss These microphones often miss many sounds because it takes a many sounds because it takes a lot of sound pressure to move the lot of sound pressure to move the coil.coil.

2) Ribbon microphones2) Ribbon microphones

Example: Beyer M 160Example: Beyer M 160

a metallic ribbon is a metallic ribbon is suspended between two suspended between two poles of a magnet. Sound poles of a magnet. Sound waves vibrate the metallic waves vibrate the metallic ribbon which causes a ribbon which causes a varying flow of electrons varying flow of electrons to the different poles of to the different poles of the magnetthe magnet

Ribbon microphonesRibbon microphonesadvantages:advantages:

These microphones capture a warmer and These microphones capture a warmer and smoother sound than dynamic/moving coil smoother sound than dynamic/moving coil microphones.microphones.

Don’t feedback much in live situations.Don’t feedback much in live situations.

Ribbon microphonesRibbon microphonestypical uses:typical uses:

Typically used in the studio because they are Typically used in the studio because they are fragilefragile

Used in close mic applications (1-12 inches)Used in close mic applications (1-12 inches)

Often used for acoustic guitars. Also work well Often used for acoustic guitars. Also work well for vocals.for vocals.

Ribbon microphonesRibbon microphonesdisadvantages:disadvantages:

colours the sound by adding a high colours the sound by adding a high frequency edge frequency edge

fragilefragile

will only pick up sounds that are very will only pick up sounds that are very close.close.

3) Condenser/Capacitor 3) Condenser/Capacitor microphonesmicrophones

Example: Audio Technica AT 4033Example: Audio Technica AT 4033

How do condenser microphones How do condenser microphones work?work?

A charged electrical current is A charged electrical current is applied to a metal-coated piece of applied to a metal-coated piece of plastic. the coating vibrates plastic. the coating vibrates sympathetically in response to a sympathetically in response to a sound wave because it is very thin.sound wave because it is very thin.

The metal-coated piece of plastic is The metal-coated piece of plastic is positioned close to a piece of metallic positioned close to a piece of metallic alloy.alloy.

The changes in the space between The changes in the space between the surfaces create a changing the surfaces create a changing discharge of electrical current.discharge of electrical current.

It makes an electrical version of It makes an electrical version of acoustic energy from the sound acoustic energy from the sound source.source.

Condenser/Capacitor microphonesCondenser/Capacitor microphonesadvantages: advantages:

they respond to fast attacks and work more they respond to fast attacks and work more precisely than other mics and add little tonal precisely than other mics and add little tonal colouration colouration

they can be used to record sounds from a they can be used to record sounds from a greater distance and capture a broader range of greater distance and capture a broader range of frequencies frequencies

big advantage: these mics record a sound while big advantage: these mics record a sound while capturing natural ambience of a room.capturing natural ambience of a room.

Condenser/Capacitor microphonesCondenser/Capacitor microphonestypical uses:typical uses:

recording studios.recording studios.

can be used to record almost any sound…except very can be used to record almost any sound…except very loud ones.loud ones.

extremely effective with quiet sounds.extremely effective with quiet sounds.

the perfect choice for capturing room ambience.the perfect choice for capturing room ambience.

almost always used for vocals , acoustic guitars and almost always used for vocals , acoustic guitars and drums.drums.

Condenser/Capacitor microphonesCondenser/Capacitor microphonesdisadvantages:disadvantages:

fairly fragilefairly fragile

feedback too easily in a live environment feedback too easily in a live environment (although some have low frequency roll off (although some have low frequency roll off switches to help alleviate feedback switches to help alleviate feedback frequencies).frequencies).

Microphone polar patterns:Microphone polar patterns:

A polar pattern is the pickup pattern of the A polar pattern is the pickup pattern of the microphone.microphone.

There are There are three three main types of patterns:main types of patterns:

1) Cardiod1) Cardiod 2) Bi-directional2) Bi-directional 3) Omnidirectional3) Omnidirectional

Frequency ResponseFrequency Response

Most microphones respond to frequencies within Most microphones respond to frequencies within and beyond the human range of hearing. and beyond the human range of hearing.

Our ears have the ability to hear frequencies Our ears have the ability to hear frequencies from 20-20 000 hertz .from 20-20 000 hertz .

All microphone manufacturers provide All microphone manufacturers provide specifications for the frequency range of their specifications for the frequency range of their products. products.

Frequency response curveFrequency response curve

The frequency response curveThe frequency response curve of a of a microphone shows how the microphone microphone shows how the microphone responds to different frequencies across the responds to different frequencies across the audible spectrum.audible spectrum.

A mic with a flat response adds little colouration A mic with a flat response adds little colouration to the sound. Many mics drop off sharply in the to the sound. Many mics drop off sharply in the frequencies below 300 hz. Yet boast frequencies frequencies below 300 hz. Yet boast frequencies in the area of 4000 hz. in the area of 4000 hz.

Pre-amplifiersPre-amplifiers

Although a microphone can be plugged Although a microphone can be plugged directly into a mixing board, better results are directly into a mixing board, better results are often achieved by using an amplifier.often achieved by using an amplifier.

ConclusionConclusion

Effective sound output requires lots of Effective sound output requires lots of experimentation. experimentation.

Most home studios should have at least Most home studios should have at least one good moving coil and one good one good moving coil and one good condenser mic. condenser mic.