Bosch IRIS-Net User Manual page 433

IRIS-Net
LOW SHELF FILTER
Low shelf filters raise or lower the magnitude response at frequencies below the cut-off frequency
without altering the response at frequencies above the cut-off frequency. Since it is not realistically possible to create
a perfect filter that alters only low frequencies without affecting high frequencies, low shelf filter design involves
compromises that allow some rounding of the corner at the filter cut-off frequency and some slope in the transition to
the unaltered high frequencies.
Element Default
6dB
1000Hz
0.0 dB
Filter Editing via "Mouse Movement" in the Graphics Display
A white dot in the frequency response display represents an active filter (BYPASS not engaged). Clicking with the left
mouse button on this dot and keeping the mouse button pressed down allows changing the filter's frequency by
moving the mouse to the left or to the right.
Bosch Security Systems B.V.
Range Description
Switches between frequency (magnitude) and phase response (phase)
indication.
Switch for selecting dB-axis scaling of 25 dB (± 12.5 dB) or 50 dB (±
25 dB).
6dB, 12dB SLOPE sets the transition band slope of the low shelf filter.
20 Hz...20 FREQUENCY sets the cut-off frequency of the low shelf filter.
kHz
-18...+18 dB GAIN defines the amplification (increase) or attenuation (reduction) of
the low shelf filter.
BYPASS switches the filter ON (not engaged) or OFF (engaged), which
allows for quick A / B-evaluation of the actual effect that the low shelf
filter has on the sound.
User Manual
DIGITAL MATRIX | en 433
2017.05 | 3.20 | F.01U.119.956