Revision C • 1/04
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3-2
3 Operation
digital
MICROPHONE PREAMPLIFIER MODULE QUICK GUIDE
This module amplifies five or ten low-level (-65 to -30 dBu) microphone signals up
to line-level (+4 dBu). The BMX
digital-8 and BMXdigital-14 come standard with five
mic preamps, the other frame sizes come standard with ten mic preamps.
The line-level balanced mono output from each preamplifier can jumper directly to
a Universal Input module; be routed through a patch bay; or connect to an external
line-level mic processor. The trim controls set the gain as required for each micro-
phone preamp. These are normally set during installation and should NOT be ad-
justed by the board operator.
Two Microphone Preamplifier modules may be installed in a BMX
digital frame to
yield twenty microphone preamplifiers.
MIC PREAMPS
Remove the security cover to access the individual preamp gain trim pots. These adjust
the preamp gain to yield a n4 dBu output for microphone input levels between
-65 dBu and -30 dBu.
PREAMP GAIN —
PREAMP GAIN —
PREAMP GAIN —
PREAMP GAIN —
PREAMP GAIN —
Separate trim controls for each microphone preamp.
