5
2.5 Connecting the outputs:
The loudspeakers should be connected to the amplifier by wires which should,
first, provide the minimum current capacity necessary for the work.
Wire minimum gauge in mm
2
(Z.500)
A wire for each speaker
1mm
2
A wire for every two speakers
1,5mm
2
Wire minimum gauge in mm
2
(Z.700)
A wire for each speaker
1,5mm
2
A wire for every two speakers
2mm
2
Wire minimum gauge in mm
2
(Z.900)
A wire for each speaker
2mm
2
A wire for every two speakers
2,5mm
2
In addition to the current capacity of the speaker connecting wires, it is
important to know as well at what distance from the amplifier the speakers are.
We may have power and damping factor losses on long-distance connections,
even with the correct gauge wire.
The following example can provide us with a magnitude order in this regard:
An 8-ohm speaker placed at 50 meters from the amplifier and connected with
a pair of 2-mm
2
wires results in a damping factor of 9 only.
A drop in the Damping Factor occurs on any amplifier, and it just takes the
presence of a wire between same and the speaker or speaker set.
On the following table see the power loss in percentage and, in parentheses, the
resulting damping factor:
(We can see in
bold letters
that the losses in long distances exceed 10%, and that the
damping factor also drops to below 10. For example, with a 12% loss on a 1000-W
amplifier, 120 watts are lost and the speakers receive 880 watts only.)
Length of the
pair of wires
(in meters)
Gauge
(mm
2
)
Power loss on the wires
for each speaker
(Damping factor)
Power loss on the wires
For each 2 speakers
(Damping Factor).
5 1
2,2%
(45)
5 1,5
1,5%
(67)
3%
(34)
5 2,0
1%
(90)
2,2%
(45)
5
2,5
0,85% (114)
1,75% (57)
5 3
0,7%
(140)
1,4%
(66)
10 1
4,4%
(23)
10 1,5
3%
(34)
6%
(16)
10 2,0
2%
(46)
4,4%
(25)
10 2,5
1,7%
(57)
3,5%
(28)
10 3
1,4%
(66)
2,8%
(33)
20 1
8,8%
(11)
20 1,5
6,0%
(16)
12% (8,3)
20 2,0
4%
(22)
8,8%
(11)
20 2,5
3,4%
(28)
7%
(10)
20 3
2,8%
(33)
6%
(16)