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lRepeat this procedure on other channels as required. As more channels are added to
the mix, the meters may move into the red section. Adjust the overall level using the
Master Faders if necessary.
lListen carefully for the characteristic sound of `feedbackî‚’. If you cannot achieve satis-
factory input level setting without feedback, check microphone and speaker place-
ment and repeat the exercise. If feedback persists, it may be necessary to use a
Graphic Equaliser to reduce the system response at particular resonant frequencies.
Note: The initial settings should only be regarded as a starting point for your mix. It is
important to remember that many factors affect the sound during a live performance,
for instance the size of the audience!
You are now ready to start building the mix and this should be done progressively,
listening carefully for each component in the mix and watching the meters for any hint of
overload. If this occurs, back off the appropriate Channel Fader slightly until the level is
out of the red segments, or adjust the Master Faders.
Remember that the mixer is a mixer, not an amplifier. Increasing the overall level is
the job of the amplifier, and if it is found impossible to provide adequate level, it is proba-
ble that the amplifier is too small for the application. Choose your amplifier carefully,
and do not try to compensate for lack of power by using the mixer to increase output
level.
Note:
The level of any source signal in the final output is affected by many factors, principal-
ly the Input Sensitivity control, Channel Fader, Sub and Mix Faders. You should try to use
only as much microphone gain as required to achieve a good balance between signals,
with the faders set as described above.
If the input gain is set too high, the channel fader will need to be pulled down too far
in compensation to leave enough trav-
el for successful mixing and there is a
greater risk of feedback because small
fader movements will have a very sig-
nificant effect on output level. Also
there will be a chance of distortion as
the signal overloads the channel and
causes clipping.
If the gain is set too low, you will
not find enough gain on the faders to
bring the signal up to an adequate
level, and backgound hjiss will be
more noticeable.
This is illustrated on the right:
If the signal level is too low it may be masked
by the noise.
Signal Noise
If the signal level is too high, clipping distortion
may occur.
Clipped
Signal
Noise