User Guide

2
GENERAL INFORMATION
SINGLE CHANNEL 31 BAND 1/3 OCTAVE GRAPHIC EQUALIZER WITH FDC
Features constant Q circuitry with a 3% center frequency accuracy. Special features include: FDC
(Feedback Detection Circuit), analog VU metering, selectable range 6dB or 12dB, active balanced
and unbalanced input/output connectors, RFI filters, variable Hi pass (low cut) and Low pass (high
cut) filters, variable input level control, passive bypass switch, clip level indicator, ground lift switch,
and selectable line voltage switch. The unit also features automatic bypass if power to the unit is lost.
TWO CHANNEL 15 BAND 2/3 OCTAVE GRAPHIC EQUALIZER
Features constant Q circuitry with a 3% center frequency accuracy. Special features include: FDC
(Feedback Detection Circuit), analog VU metering, selectable range 6dB or 12dB, active balanced
and unbalanced input/output connectors, RFI filers, variable input level control, passive bypass
switch, clip level indicators, ground lift switch, and selectable line voltage switch. The unit also
features automatic bypass if power to the unit is lost.
FDC - ART’s FEEDBACK DETECTION CIRCUIT
FDC (Feedback Detection Circuitry – designed and developed by ART Engineering) instantly
illuminates the corresponding EQ band with the greatest signal. That is, if feedback occurs, FDC
identifies the band with the feedback frequency for quick correction.
During operation, various LED’s will illuminate as it passes signal. The loudest band will correspond
with the brightest LED. When you hear feedback, FDC (and it’s brightest LED) shows you where to
attenuate.
FDC confirms what you hear (feedback), and shows you exactly where it is. You’ll also know you
have properly attenuated the signal as the LED reduces its illumination. FDC - it is both precise and
simple.
FDC APPLICATIONS
FDC allows you to observe those frequency bands with the greatest energy when program material is
being played. In a live sound system where the HQ EQ is in the path between a microphone and
loudspeakers, dominant room modes may be seen as bands with a lot of energy when the sound