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If you find it difficult to make your sound loud enough without ringing, you need more gain
before feedback. Here’s some simple ways to get it:
•
Train participants and stage handlers
so that everyone speaks between 4" and 6" from their
microphones. Aim boom mics so they point toward the speaker’s chin
when the speaker is looking
straight out at the audience
. Good miking lets everyone be heard with lower gain, resulting in
sufficient sound without feedback problems.
•
The
VGM-804's
sound gating
automatically increases your available gain before feedback, by muting
unused microphones. Unneeded mics receive no useful sound, only feedback and noise. You win
about 30% more headroom for each mic shut off.
•
Don’t use excessive compression
. If any mic input is causing the
COMPRESS
LED to glow
red
, reduce
that input’s level control.
•
Anything you can do to provide a
quiet auditorium
directly adds to your available gain before
feedback. For example, keep auditorium doors closed during the program, to deflect lobby noise.
If your HVAC system makes excessive noise, see if anything can be done to quiet it.
Thanks to the sound gating feature, there’s far less need for you to turn mics up and
down during the program. We still recommend, however, turning down mics that are
obviously finding only noise:
•
Stand
mics being moved
by stage handlers
•
Certain wireless receivers that pick up
radio noise
when their mics are switched OFF – turn up wireless
mics only after they’ve been switched ON.
In short, working this mixer is like driving with cruise control – it makes your job
easier, but you still have to drive. Here’s some “safety tips.”
•
When you hear ringing
, reduce gain on the affected mic(s). You’ll know which mics are causing
ringing by watching the mixer’s
GATE
LEDs while listening for the ringing. Mics gated “off” cannot
contribute to ringing at that moment.
•
The
COMPRESS
LED may glow
green
or perhaps yellow momentarily at “high points” in the material.
That’s good – it indicates you’re providing maximum usable sound.
•
When accidents happen
– a dropped mic, a cough, or a feedback howl – the mixer limits these nasty
sounds (the
COMPRESS
LED lights
red
).
•
If the
COMPRESS
LED lights
red
for normal material, your mic gain(s) are set too high! Turn them down
until the mixer indicates only a slight, intermittent compression. You’ll get clearer, more natural
sound and less feedback. In this situation, turn up your power amplifier should you need more sound.
