Owner`s manual

ManualsBrandsRotel Manualsaudio & home theatreRMB-1585

RMB-1555/RMB-1585 Five Channel Power Ampliﬁers

If this happens, turn the ampliﬁer off, let it cool down for several minutes,

and attempt to identify and correct the problem. When you turn the

ampliﬁer back on, the protection circuit will automatically reset and the

Power Indicator should light up, indicating that the ampliﬁer is turned

on normal.

In most cases, the protection circuitry activates because of a fault condition

such as shorted speaker wires, or inadequate ventilation leading to an

overheating condition. In very rare cases, highly reactive or extremely low

impedance speaker loads could cause the protection circuit to engage.

If the protection circuitry triggers repeatedly and you are unable to isolate

and correct the faulty condition, contact your authorized Rotel dealer for

assistance in troubleshooting

Input Signal Connections

The RMB-1555 and RMB-1585 have conventional RCA type input

connectors and (RMB-1585 only) accept Balanced (XLR) input connectors,

the type found on nearly all audio equipment. Only one set of inputs

should be connected. Never connected both Balanced and RCA inputs

at the same time.

NOTE: To prevent loud potentially damaging noises, make sure the

amplifier is turned off when you make any changes to the input signal

configuration.

Select high quality audio interconnect cables. Connect each of the

outputs from the preampliﬁer or signal processor to the corresponding

input of the ampliﬁer.

Speaker Connection

Speaker Selection

We recommend using loudspeakers with a nominal impedance of 4 ohms

or higher with the RMB-1555 and RMB-1585. You should exercise some

caution in driving multiple pairs of speakers in parallel conﬁguration,

because 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, it is recommended

that you select speakers with a nominal impedance of 8 ohms or higher.

Speaker impedance ratings are less than precise. In practice, very few

loudspeakers will present any problems for the RMB-1555 or RMB-1585.

See your authorized Rotel dealer if you have any questions.

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

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 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 Connections

NOTE: The following text describes both binding post and plug-in

connections. DO NOT use both connection methods in combination to

connect multiple speakers.

Turn off all the components in the system before connecting the speakers.

The RMB-1555 and RMB-1585 have two color coded binding posts, two

for each channel. These connectors accept bare wire, connector lugs,

or dual banana type connectors (except in the European Community

countries where their use is not permitted).

Route the wire from the ampliﬁer to the speakers. Give yourself enough

slack so you can move the components to allow access to the speaker

connectors.

If you are using dual banana plugs, connect them to the wires and then

plug into the backs of the binding posts. The thumbscrews of the binding

posts 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 binding posts, separate the wire

conductors and strip the insulation from the end of each conductor. Be

careful not to cut into the wire strands. Unscrew (turn counterclockwise)

the binding post. Place the connector lug or wire around the binding

post shaft. Turn the binding post 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.