Mackie THUMP 212, Руководство пользователя

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Thump212 and Thump215 Powered Loudspeaker Series
9. Sig/OL LED
This dual-colored LED will illuminate green
when the input signal is present, indicating signal.
Thump loudspeakers have a built-in limiter that
helps to prevent the amplifier outputs from clipping
or overdriving the transducers. The LED illuminates
red when the limiter is activated. It’s okay for it to blink
red occasionally, but if it blinks frequently or lights
continuously, turn down the gain knob until it only
blinks occasionally.
Excessive limiting may lead
to overheating, which in turn
trips the thermal protect circuitry
and interrupts the performance. See ‘Thermal
Protection’ on page 14 for more information.
10. Music Ducking
Have you been to an event where music was playing,
then when someone spoke into the mic, that the music
volume decreased greatly (but was still there)? That’s
called “music ducking”!
When the music ducking switch is engaged,
the channel 2 level will decrease when a mic signal
is present on channel 1. As if by magic, once the
speaking is completed, the music will return back to its
previous level. True wizards, those engineers... and
none of them have long grey beards, robes and pointy
hats.
The audio nerds out there might like
to know that the channel 2 level decreases
by 10 dBu when a mic signal is present
in channel 1 (and when auto-ducking
is engaged, of course).
11. Feedback Eliminator
The multi-band feedback eliminator hunts
down offending feedback frequencies and applies
up to six notch filters automatically to destroy
feedback and maximize gain prior to feedback.
This is a great tool for when an engineer is not present.
• Off [Default] – The feedback eliminator is not
engaged. If filters have been applied, this setting will
retain its current filter settings if there are any, but they
will not be engaged until it is turned back on.
• On – When the automatic feedback eliminator is
turned on, scanning occurs continuously. The six filters
will engage sequentially when feedback is present until
all are used and then it will be locked. If feedback is
identified on an existing filter, the notch will deepen in
three steps to further destroy the offending feedback
frequency. Pretty cool, huh?
The feedback eliminator ONLY affects
channel 1 (mic and line mode).
DUCKING FB ELIMINATOR SIG/OL
OFF
ON
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Thump Series Loudspeakers: Rear Panel Features continued...