User manual

4-2 E-PAC (V02) User Manual
Vertically stacking the cabinets, rather than horizontally arraying
them is particularly useful in deep rooms where more than one
cabinet has to be used because a single cabinet has insufficient
throw for the level needed at the back of the room. This helps
reduce interference in the horizontal plane and gives more vertical
directivity.
4.2. Wiring
In order to keep losses in tone and power low the length of cable
run between mainframe and loudspeaker should be kept as short
as possible. A conductor size of 1.5 mm
2
(16 AWG) is the minimum
requirement, 2.5 mm
2
(12 AWG) is preferable.
When full range loudspeakers and actively driven subwoofers are
operated together, then - due to the different pin assignments of
the systems - four-core cables have to be used.
We recommend the use of d&b MC4 cable (4 x 2.5 mm
2
/ 4 cond.
12 AWG). MC4 cables retain their flexibility even at low
temperatures and can be supplied in various lengths.
If very long cable runs are unavoidable in an installation, a
conductor size greater than 2.5 mm
2
(12 AWG) may be needed to
reduce power loss and to achieve an acceptable damping factor
(relation of load impedance to cable impedance). If the individual
conductor size in a cable is insufficient, then it’s permissible to use
two or more of the conductors.
The following ‘rule of thumb’ formula allows you to estimate the
maximum cable length with an acceptable damping factor (>10):
maximum (single) length of cable [m] =
3 x load impedance [ohms] x cross-section [mm
2
]
The parallel wired connectors fitted to all C-Series and E-Series
loudspeakers allow the mainframe output signal to be fed directly
from one cabinet to another dispensing with the need for signal
distribution boxes.