AKG Acoustics C 451 B Microphone User Manual


 
The rod-shaped body, accurate response, and many matching
accessories from AKG make it easy to use the microphone to
pick up a wide range of different instruments.
Read the hints below to get the best possible results.
Owing to their acoustic principle, unidirectional microphones
exhibit what is called "proximity effect". This means that the low-
frequency content of a sound signal will be progressively boost-
ed as you move the microphone closer to the sound source.
Proximity effect begins to become audible at a working distance
of about 2 feet (60 cm). Depending on the nature of the sound
source, proximity effect may be desirable or a nuisance.
Place the microphone closer to the sound source to accentuate,
or further away to reduce proximity effect.
Feedback results from part of the sound projected by a speaker
being picked up by a microphone, fed to the amplifier, and pro-
jected again by the speaker. Above a specific volume or “system
gain” setting called the feedback threshold, the signal starts be-
ing regenerated indefinitely, making the sound system howl and
the sound engineer desperately dive for the master fader to re-
duce the volume and stop the howl ing.
4 Using Your Microphone
18
C 451 B
4.1 Introduction
4.2 Proximity Effect
4.3 Feedback in Live
Sound Situations
Fig. 3: Microphone
placement for max imum
gain before feedback.