953.160UK User Manual
Speaker outputs
The RM406 has a separate speaker output for each zone, connected via 3 large modular terminal plugs.
Each plug can be removed from the rear panel for convenient connection of speaker outputs to 2 zones.
Each zone output can be used to power either 100V line speakers or standard low impedance speakers.
These 2 configurations cannot be used together, so it is important to decide which will be used at the start.
100V line systems
For 100V speakers, connect the selected zone output to the first speaker in the zone using double-insulated
speaker wire which has adequate current rating to handle the total output of the amplifier.
C
onnect the “100V” output terminal
for the selected zone to the positive (+) connection of the speaker and
“COM”
output to the negative (-) connection of the speaker. Connect further speakers in parallel to the first
speaker with all positive terminals and connected together and all negative terminals connected together as
shown below.
A 100V line speaker system can comprise of many speakers connected together. The determining factor for
how many speakers can be used on a single amplifier is the power rating. For most purposes, it is advised to
connect as many speakers as needed with a combined wattage of no more than 90% of the a
mplifier’s output
power rating (in the case of the RM406, this is 40W per zone output)
The terminals of a 100V speaker are connected via a transformer and if necessary, this transformer may be
“tapped” for different power ratings.
These tappings can be used to adjust the wattage (and output volume)
of each speaker in a zone to help achieve the ideal total power of the system for the relevant zone output.
Low impedance systems
Alternatively, each zone output of the RM406 is capable of powering one or more low impedance speakers.
There is an option on each zone for either a 4
Ω
or 8
Ω
speaker output to determine the minimum impedance.
It is essential to select the correct output terminal when opting for low impedance speakers.
For a single 8
Ω
speaker, connect the positive (+) wire to the “8Ω” terminal and the negative (
-) wire t
o “COM”
For a single 4
Ω
speaker or for 2 x 8
Ω
speakers connected in parallel, connect the positive (+) wire to the “4Ω”
terminal and the negative (-
) wire to “COM”
In either case, the connected load should have a combined impedance no lower than stated on the terminal.
Lower impedance may cause irreparable damage to the amplifier.
The connected speaker(s) must also have a power handling to accept up to 40Wrms from the zone output.
Lower power handling may risk damage to the speakers.
