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English

conductor. Be careful not to cut into the wire strands. Unscrew (turn 
counterclockwise)  the speaker connector collar. Place the connector 
lug around the shaft, or insert the bundled wire into the hole in the 
shaft. Turn the collars clockwise to clamp the connector lug or wire 
firmly in place.

For each group of channels, connect the left speaker to the pair of 
speaker connectors labeled LEFT. Connect the right speaker to the 
speaker connectors labeled RIGHT. Follow the labels printed above 
the connectors. Make sure that the positive terminal of the speaker 
is connected to the + terminal on the amplifier. Make sure that the 
negative terminal of the speaker is connected to the terminal of the 
amplifier.

Note:

 Be sure there are no loose wire strands that could touch 

adjacent wires or connectors

Plug connection 

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Connect your speaker wires as shown in the illustration. Insert the wire 
into the open and turn the screw to clamp the wire in place. 

Be sure to keep the polarity of the connections correct.

Speaker Selection 

The nominal impedance of the loudspeaker(s) connected to the RMB-
1512 should be a minimum of 4 ohms. When driving multiple pairs of 
speakers connected in parallel, the effective impedance the amplifier 
sees is cut in half. For example, when driving two pair of 8 ohm 
speakers, the amplifier sees a 4 ohm load. When driving multiple 
speakers in parallel, select speakers with a nominal impedance of 8 
ohms or higher.

Speaker Wire Selection 

Use insulated two-conductor stranded wire to connect the RMB-1512 
to the speakers. The size and quality of the wire can have an audible 
effect on the performance of the system. Standard speaker wire will 
work, but can result in lower output or diminished bass response, 
particularly over longer distances. In general, heavier wire will 
improve the sound. For best performance, you may want to consider 
special high-quality speaker cables.Your authorized Rotel dealer can 
help in the selection of cables for your system. 

Polarity and Phasing 

The polarity or positive/negative orientation of the connections for 
every speaker and amplifier connection must be consistent so all 
the speakers will be in phase. If the polarity of one connection is 
mistakenly reversed, bass output will be very weak and stereo imaging 
degraded. All wire is marked so you can identify the two conductors. 
There may be ribs or a stripe on the insulation of one conductor. The 
wire may have clear insulation with different color conductors (copper 
and silver). There may be polarity indications printed on the insulation. 
Identify the positive and negative conductors and be consistent with 
every speaker and amplifier connection.

Speaker Wire Connection 

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See Figure 2

Route the wires from the RMB-1512 to the speakers. Give yourself 
enough slack so you can move the components to allow access to the 
speaker connectors.

The RMB-1512 has two pair of color-coded speaker connectors for 
each group of amplifier channels, one for the left speaker, the other 
for the right speaker. Labels above the connectors show the proper 
connections for connecting speakers. These speaker connectors accept 
bare wire, connector lugs, or “banana” type connectors (except in the 
European Community countries where there use is not permitted).

The RMB-1512 also has a plug-in speaker connector that can make 
connection easier in custom installations. You can pre-wire the plug-in 
connector before the amplifier is installed. The plug-in connector is 
wires in parallel with the bind post outputs.

Note:

 The following text describes both binding post and plug-in 

connections. DO NOT use both connection methods in combination to 
connect multiple speakers.

Binding Post connection 

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If you are using banana plugs, connect them to the wires and then 
plug into the backs of the binding posts. The collars of the speaker 
connectors should be screwed in all the way (clockwise). 

If you are using terminal lugs, connect them to the wires. If you are 
attaching bare wires directly to the speaker connectors, separate the 
wire conductors and strip back the insulation from the end of each 

R+

R--

L--

L+