M-Audio Microphone, Руководство пользователя

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have very low output, thereby requiring more electronic gain a factor that necessitates
high-quality preamp electronics in order to avoid noise.
Condenser microphones
Condenser
mics are the most common for studio use. A thin
electrically conductive diaphragm is suspended over a back plate,
forming a delicate flexible capacitor.When sound waves excite the
diaphragm, the distance between the diaphragm and back plate
changes and with it the capacitance.This capacitance change, in
turn, produces a voltage change. Associated circuitry converts
these variations in voltage to a signal that is sent to the preamp.
The power required by this design is serviced by the 48-volt
phantom power commonly found on preamps and mixer inputs.
The diaphragms of condenser microphones are made of extremely thin metal or metalized plastic
similar in thickness to kitchen plastic wrap. Their thinness makes condenser mics very accurate in
frequency response and extremely sensitive to transients, such as the initial crack of a drum being
struck. In addition to imparting the least sonic coloration of any microphone design, the sensitivity
of condensers extends much further from the source than other mics, thus allowing greater
flexibility.This greater sensitivity also provides the engineer with the option of picking up more the
room ambience a factor that can add a great deal of realism to a recording.
Condensers are more delicate than moving-coil dynamics, yet much more resilient than ribbons.
Due to sensitivity to low-frequency handling noise and the delicacy of the diaphragm, condensers
are invariably used in conjunction with a shock mount, and often with the addition of a pop filter.
The sonic characteristics of condensers and the need for TLC make them more ideally suited for
studio recording. That is not to say that condensers can t be used for some tasks on stage
just that the environment should be controlled, such as in a professional show where cables
are secured, mics are shock-mounted against vibration, and the stage is restricted to
professional personnel.
Since condenser construction technology is much more labor-intensive and sophisticated
compared to that of dynamics, good quality condensers tend to cost comparatively more money.
Condensers are excellent choices for miking vocals, acoustic guitar, piano, orchestral instruments,
saxophone, percussion and sound effects. As condensers are the predominant type of microphone
for studio use, this guide will focus on condenser applications.
Capsule Size
The capsule incorporates the all-important diaphragm
assembly that translates sound pressure into an electric
signal. Condenser capsules come in three basic sizes
small, medium and large. Generally speaking, frequency
response is a function of diaphragm size. Consider what
happens with speakers of different size. As woofers get
larger, they become more efficient at producing low
frequencies and less efficient at producing high frequencies.
In general, the same is true as the diameters of diaphragms
increase (with some caveats we ll cover in a minute).
Signal-to-noise ratio of the microphone as a whole generally owes in part to diaphragm size. The
more surface area that a diaphragm has, the greater its potential sensitivity to sound pressure and
the stronger the output signal. As a result, large diaphragms inherently exhibit much better
signa-to-noise ratios than do small ones.
small capsule
medium capsule
large capsule
20 20k 10k 15k 1k
20 20k 10k 15k 1k
20 20k 10k 15k 1k
Without intervention, microphones tend to be
less linear as the diaphragm size increases
fixed magnet
ultra -thin diaphragm
solid backplate
capacitance
output
signal
In condenser mics, sound waves hitting
the diaphragm change the capacitance
in the field between the charged
diaphragm and backplate
Choosing & Using Microphones
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