CABLE REQUIREMENTS
Input Cables
Make sure to use only shielded cables whether balanced or unbalanced. Shielding,
when properly grounded, protects a signal against external electrical interference.
As a rule, unbalanced lines over 3 meters long are not acceptable. Greater distances
require a balanced cable. Avoid placing input cables close to power cords or power
transformers.
Output Cables
The amplifier is capable of delivering high level output current; therefore, the wire
gauge used for speaker cables is particularly important. Inadequate wire gauge adds
significant resistance to the speaker’s own impedance, reducing the power, which is
actually delivered to the speaker. It will also result in a decreased damping factor and
possible fire hazard.
Since the power, applied to the loudspeaker, is of primary concern in system design,
we have included the table below to allow you determine the appropriate wire gauge for
your application.
Power Loss in a 10-meter Cable
The table shows the percentage of the power loss in a 10-meter copper multiple-core
cable. This table reflects the power loss as a percentage of the output power of the
amplifier applied to the load. Use this table to determine the power loss to the load at other
cable lengths. For example, if you plan to deliver 100 Watts to 8-Ohms load through 20-m
2
cable of 0.75-mm gauge, the power loss in the cable would be 5.8 % x 2=11.6 % of 100 W
or 11.6 W lost in the cable.
2
0.50 mm
2
0.75 mm
2
1.00 mm
2
1.50 mm
2
2.00 mm
2
2.50 mm
2
4.00 mm
0.72 Ohms
0.49 Ohms
0.36 Ohms
0.24 Ohms
0.18 Ohms
0,15 Ohms
0.09 Ohms
15.4 %
10.9 %
8.3 %
5.7 %
4.3 %
3.6 %
2.3 %
8.3 %
5.8 %
4.3 %
2.9 %
2.2 %
1.8 %
1.1 %
Wire Gauge
Cable
Resistance
Cable Power Loss
4 Ohms Load
8 Ohms Load
9
