Rotel RB-1572 Input Signal Connections, Speaker Connections, Turn On/Off Mode Selector

	RB-1562 / RB-1572 Stereo Power Amplifiers
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Turn On/Off Mode Selector 3

The amplifier can be turned on and off automatically by using its “12V Trigger” system. The Turn On/Off Mode Selector switch is used to select which method is used.

•With the switch in the OFF position, the amplifier is turned on or off manually using the front panel power switch.

•With the switch in the 12V TRIG. position, the amplifier is turned on automatically when a 12 volt trigger signal is applied to the 3.5mm Jack labeled IN. The front panel POWER SWITCH overrides this function. It must be ON for the +12V trigger to work. Turning the switch OFF cuts power to the amplifier, regardless of whether or not a trigger signal is present.

+12V Trigger Input and Output 4

The jack labeled IN is for connecting the 3.5mm Plug/Cable carrying a +12 volt trigger signal to turn the amplifier on and off. To use this feature the adjacent switch 3 must be set in the ON position (see previous section). This input accepts any control signal (AC or DC) ranging from 3 volts to 30 volts.

The jack labeled OUT is for connecting another 3.5mm plug/cable to provide a 12V trigger signal to other components. The 12V output signal is available whenever a +12 volt trigger signal is applied to the IN connector.

Input Signal Connections 6

See Figure 2

The RB-1562 and RB-1572 have standard unbalanced RCA-type input connectors, the type used on nearly all audio equipment. There is an RCA input for each of the two amplifier channels. These RCA inputs accept audio signals from preamplifiers or surround sound processors. Use high quality audio interconnect cables for best performance.

Speaker Connections

See Figure 2

The RB-1562 and RB-1572 have two sets of dual binding post speaker connection terminals, for each amplifier channel.

Speaker Selection

The nominal impedance of the loudspeaker(s) connected to each channel of the amplifier should be no lower than 4 ohms.

Speaker Wire Selection

Use insulated two-conductor stranded wire to connect the amplifier 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 appropriate cables for your system.

Polarity and Phasing

The polarity – the 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 Connections 5

Note: The following text describes both binding post and banana plug connections. DO NOT use both connection methods in combination to connect multiple speakers.

The amplifier has two sets of color coded terminals for each amplifier channel. Having two sets of terminals for each channel makes it easy to bi-wire the speakers. The speaker terminals 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 amplifier to the speakers. Give yourself enough slack so you can move the components to allow access to the speaker connectors.

Note: Be sure to notice the location of the LEFT and RIGHT speaker terminals and connect your LEFT and RIGHT speakers to the correct outputs. Take extra care if using two sets of wires to bi-wire your speakers.

If you are using banana plugs, connect them to the wires and then plug into the backs of the speaker connectors. When using banana plugs, the collars of the binding post terminals 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 conductor. Be careful not to cut into the wire strands. Unscrew (turn counterclockwise) the binding post 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.

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