Nexo LS18 - Manual (Page 12)

Page 12/103 GEO S12 G ENERAL S ET - UP I NSTRUCTIONS
2.1.4 Cabling
NEXO recommends the exclusive use of multi-conductor cables to connect the system: the cable kit is
compatible with all the cabinets, and there is no possible confusion between LF, MF and HF sections.
Cable choice consists mainly of selecting cables of the correct sectional dimension (size) in relation to
the load resistance and the cable length. Too small a cable section will increase both its serial
resistance and its capacitance; this reduces the electrical power delivered to the loudspeaker and can
also induce response (damping factor) variations.
For a serial resistance less or equal to 4% of the load impedance (damping factor = 25), the maximum
cable length is given by:
L
max
= Z x S S in mm
2
, Z in Ohm, L
max
in meters
The table below indicates these values, for 3 common sizes.
Load Impedance (  ) 2 3 4 6 8 12 16
Cable section Maximum Length (meters)
1,5 mm² (AWG #14) 3 4.5 6 9 12 18 24
2,5 mm² (AWG #12) 5 7.5 10 15 20 30 40
4 mm² (AWG #10) 8 12 16 24 32 48 64
2.1.5 Example:
 GEO S12 has a 16 Ohms nominal impedance in passive mode, so 4x Geo S12 wired in
parallel will present a 16/4 = 4 Ohm load impedance. The maximum acceptable 2x2.5
mm
2 (AWG #12) cable length L
max
for such a cluster is 10 meters.
IMPORTANT
Long speaker cables induce capacitive effects
– up to hundreds of pF depending on the
quality of the cable - with a low-pass effect on high frequencies. If long speaker cables
must be used, ensure that they do not remain coiled while in use.