Rotel RB-1066 Troubleshooting, Polarity and Phasing, Speaker Connections, No Sound, See Figures

RMB-1066Six Channel Power Amplifier 8

Polarity and Phasing

The polarity – the positive/negative orienta- tion 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 re- versed, bass output will be very weak and ste- reo 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 insula- tion 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 Connections

See Figures 2 & 3

The RMB-1066 has two pair of color coded connections for each group of amplifier chan- nels. Labels above the connectors show the proper connections for connecting speakers in Stereo mode. Labels below show the proper connections for Bridged Mono mode.

These speaker connectors accept bare wire, connector lugs, or “banana” type connectors (except in the European Community countries where their use is not permitted).

Route the wires from the RMB-1066 to the speakers. Give yourself enough slack so you can move the components to allow access to the speaker connectors.

If you are using banana plugs, connect them to the wires and then plug into the backs of the speaker connectors. 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 insula- tion from the end of each 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 con- nector lug or wire firmly in place.

NOTE: Be sure there are no loose wire strands that could touch adjacent wires or connectors.

In Stereo mode: 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, observe cor- rect polarity, and make sure the INPUT SE- LECT switch for that pair of amplifier chan- nels is set to the STEREO position. (See Fig- ure 2)

In Bridged Mono mode: Connect each speaker to the POSITIVE terminals of the LEFT and RIGHT speaker connections on the back of the RMB-1066. There are BRIDGED + and

–labels printed below each group of speaker terminals to assist in maintaining proper polar- ity.

Connect the positive terminal of the speaker to the speaker connector labeled LEFT + or BRIDGED +. Connect the negative terminal of the speaker to the speaker connector labeled RIGHT + or BRIDGED –. Observe correct polarity, and make sure the INPUT SELECT switch is set to the BRIDGED position. (See Figure 3)

Troubleshooting

Most difficulties in audio systems are the re- sult of poor or wrong connections, or improper control settings. If you encounter problems, isolate the area of the difficulty, check the control settings, determine the cause of the fault and make the necessary changes. If you are unable to get sound from the RMB-1066, refer to the suggestions for the following conditions:

Front Panel Power Indicator Is Not Lit

No main power to the RMB-1066. Check AC power connections at the amplifier and the AC outlet. Check the front panel power switch. Make sure that it is set to the ON position. If using signal sensing auto power-on, make sure that a signal is present at the inputs. If using 12V trigger power-on, make sure that a trigger signal is present at rear panel screw termi- nals.

No Sound

If the amp is getting AC power, but is pro- ducing no sound, check the PROTECTION INDICATORS on the front panel. If lit, see below. If not, check all of your connections and control settings on associated components. Make sure that your input connections and speaker connections match your selected ste- reo/mono configuration.

Protection Indicator Is Lit

The front panel PROTECTION INDICATORS light when the RMB-1066 protection circuits have shut off the amplifier. Typically, this oc- curs only when the ventilation openings are blocked, when there is faulty speaker wiring, or after a period of extreme use. Turn off the system and wait for the amp to cool. Then push the front panel power switch in and out to reset the protection devices. If the problem is not corrected or reoccurs, there is a problem with the system or the amplifier itself.