Art HQ 15 User Manual page 6

turn on your equalizer BEFORE your power amplifiers are turned on, and always turn off your
equalizer AFTER your power amplifiers have been turned off.
2. FILTER LEVEL CONTROLS
Each of these sliders controls the output level of each of the 31 (or 15) bandpass filters. A detent at
the center position helps center the controls for a flat response.
3. FILTER RANGE SWITCH & INDICATORS
The gain range of the filter sliders is switchable (as a group) from +/- 6dB to + /-12dB for maximum
boost/cut capability. At 6dB the green LED will illuminate and at 12dB the yellow LED will illuminate.
4. BYPASS SWITCH & CLIP INDICATOR LED
Bypass Switch: When the red LED is illuminated, this indicates that the unit or channel is in
the bypass mode. Signal is routed directly from the input to the output without passing through
any circuit (often referred to as "hard-wire bypass"). Use this switch to compare equalized and
unequalized material, or to bypass the EQ section in the event of power loss or unit failure.
Clip Indicator: - This red LED illuminates if any section of the equalizer is within 5dB of
clipping. Occasional flickering of this LED is acceptable, but if it remains on more than
intermittently you should turn down either the equalizer's level controls or reduce the output
level of the preceding component to avoid audible distortion.
5. HI PASS FILTER (LOW-CUT FREQUENCY CONTROL)
To cut down on unwanted low frequency signals, this control determines the roll-off frequency of the
High-Pass Filter (HPF). The roll-off frequency can be adjusted from 10Hz to 250Hz by turning this
knob. Because of its high roll-off slope, the HPF can be efficiently used to cut down the "HUM" noise
from preceding instruments, or to reduce low frequency resonances, when speakers are installed in
an enclosed acoustic environment.
6. LOW PASS FILTER (HIGH-CUT FREQUENCY CONTROL)
To cut down on unwanted high frequency signals, this control determines the roll-off frequency of the
Low-Pass Filter (LPF). The roll-off frequency can be adjusted from 3kHz to 40kHz by turning the
knob. Because of its high roll-off slope, the LPF can be effectively used to cut down the high
frequency noise from preceding instruments, or roll-off excessive high frequency sounds to obtain a
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