Nexo GEO M12 Series, System Manual

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GEO M12 GENERAL SET-UP INSTRUCTIONS Page 11/90
2.3 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 recommended
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
Cable section Recommended Cable Length
1,5 mm² (AWG #14) 3m/10ft 4.5m/13ft 6m/20ft 9m/30ft 12m/39ft
2,5 mm² (AWG #12) 5m/16ft 7.5m/23ft 10m/33ft 15m/49ft 20m/66ft
4 mm² (AWG #10) 8m/26ft 12m/39ft 16m/52ft 24m/79ft 32m/105ft
Maximum allowed length is 4 times recommended length.
Example:
GEO M12 module has a 8

nominal impedance in passive mode. When connecting 4 modules in parallel,
total load impedance become 2

.
Recommended length for 4mm
2
/ (AWG#10) is 8m / 26ft, maximum allowed length is 32m / 105ft.
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.
2.4 GEO M12 & MSUB18 recommended amplification
NEXO TD Controllers Recommended amplification
NXAMP4x1mk2 Powered Controller Bridged Stereo mode
(2x2.6kW/4

)
2 x GEO M12 in passive mode per bridged channel
1 x MSUB18 per bridged channel
NXAMP4x2mk2 Powered Controller 4 channels mode
(4x2.5kW/2

)
1 x GEO M12 in passive mode per channel
1 x MSUB18 per channel
NXAMP4x4 Powered Controller 4 channels mode
(4x4kW/2

)
3 x GEO M12 in passive mode per channel
3 x GEO M12 in active mode: 2 channels
2 x MSUB18 per channel
2.5 GEO M12 & MSUB18 setups on NEXO TD Controllers
Please consult nexo-sa.com for NEXO TD Controllers firmware information.