D&b Audiotechnik J-SUB Manual - page 7
In its standard mode the J-SUB can be used as subwoofer for
applicable d&b loudspeaker systems operated in CUT mode. In
this mode the two channels of the system are tuned to create a
cardioid dispersion pattern thus providing maximum rejection to the
rear. It can be used in flown or stacked combinations with a
minimum distance of 60 cm (2 ft) between adjacent columns of
cabinets.
2.3.1. Controller settings
For acoustic adjustment the INFRA and HCD function can be
selected.
INFRA circuit
If the INFRA circuit is selected, the upper operating frequency of
the system is reduced from 100 Hz to 70 Hz. The J-SUB can now
be used to supplement applicable d&b loudspeaker systems
operated in full range mode.
HCD circuit
Cardioid polar pattern
Hypercardioid polar pattern
Selecting HCD (Hypercardioid) optimizes the tuning of front and
rear channels for a maximum rejection at the left and right sides
behind the cabinet providing a hypercardioid dispersion pattern.
This characteristic is particularly useful for a setup with subwoofers
stacked at the left and right sides of a stage providing minimum
interference onstage.
HCD mode can be used either freely radiating or in front of walls.
The minimum distance to rear walls is provided by the wheels on
the cabinet back. Even in HCD mode adjacent columns of J-SUBs
have to be at least 60 cm (2 ft) apart.
d&b J-SUB Manual 2.1 en
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