Bridged Mode
The SI-2125’s bridged mode switch allows you to create a more powerful
amplifier by combining both channels into one (8 ohm minumum). In the bridged
mode, connect the speakers to the left red positive terminal and the right red
positive terminal. In the bridged mode the right channel’s red terminal becomes
positive and the left channel's red terminal becomes negative.
DO NOT USE THE BLACK NEGATIVE (-) TERMINALS. THE SIGNAL IS AT THE
RED POSITIVE (+) TERMINALS ONLY.
Multiple Speaker Loads
The SI-2125 is stable into very low impedance loads. This means you can safely
operate three pairs of 8 ohm speakers (a 2.67 ohm load) directly connected to the
SI-2125. Note that the SI-2125 does not have on/off speaker switching built in.
When the amplifier is on, so are all of the speakers. (for more information on
proper amplifier placement, see Installation Considerations on page 5, Figure 2).
Niles makes a number of different speaker selection and impedance matching systems.
Speaker selection systems allow each pair of speakers to be turned on and off from your
equipment location (or even via remote control). That way, you know that the speakers
in the bedroom are off so you can avoid waking a sleeping spouse! These speaker
selectors provide an easy way to terminate all of the wires for more than three pairs.
Testing and troubleshooting a new system is much easier with the individual room
labels and on/off switches of a Niles speaker selection system. Additionally, Niles
speaker selection systems offer impedance matching features which will allow you to
connect up to ten pairs of speakers to your SI-2125 amplifier.
INSTALLATION CONSIDERATIONS
7
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Wire size is expressed by its AWG (American
Wire Gauge) number. The lower the number, the
larger the wire, i.e. twelve AWG is physically
larger than fourteen AWG.
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