User manual ROTEL RA-840BX4

[. . . ] Immediately stop using the component and have it inspected and/or serviced by a qualified service agency if: · The unit has been dropped or damaged in any way Place the unit on a fixed, level surface strong enough to support its weight. A family whose passionate interest in music led them to manufacture high fidelity components of uncompromising quality founded Rotel over 30 years ago. Through the years that passion has remained undiminished and the family goal of providing exceptional value for audiophiles and music lovers, regardless of their budget, is shared by all Rotel employees. The engineers work as a close team, listening to, and fine tuning each new product until it reaches their exacting musical standards. [. . . ] in addition , all of us at Rotel welcome your questions and comments. Save the RA-840BX4 shipping carton and all enclosed packing material for future use. Shipping or moving the RA-840BX4 in anything other than the original packing material may result in severe damage to your amplifier. Fill out and send in the owner's registration card packed with the RA-840BX4. It is your best record of the date of purchase, which you will need in the event warranty service is ever required. The heat sinks and ventilation openings in the amplifier are designed to dissipate this heat. There should be 10 cm (4 inches) of clearance around the chassis, and reasonable airflow through the installation location, to prevent the amplifier from overheating. Likewise, remember the weight of the amplifier when you select an installation location. Make sure that the shelf or cabinet can support its considerable bulk. If you are going to be away from home for an extended period of time such as a monthlong vacation, it is a sensible precaution to unplug your amplifier (as well as other audio and video components) while you are away. Instead, the protection circuit monitors the temperature of the output devices and shuts down the amplifier if temperatures exceed safe limits. Connect the left channel output of your preamp to the left channel input on the RA-840BX4. In order to use the RA-840BX4 in bridged mode, three "jumper" connectors inside the amplifier must be moved from one set of pins to another. In addition the RA-840BX4 is connected to the other components in a different way. When the RA-840BX4 is setup for bridged operation on the the Bridged Mono indicator light front panel will light. We recommend using loudspeakers with a nominal impedance of 4 ohms or higher with the RA-840BX4. 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. In practice, very few loudspeakers will present any problems for the RA-840BX4. The RA-840BX4 has two pairs of color coded binding posts on the back panel. These connectors accept bare wire, connector lugs, or dual banana type connectors (except in the European Community countries where their use is not permitted). [. . . ] In this configuration the single channel produces a massive 330 watts!This feature allows you to increase the overall power output of your system by bridging the RA-840BX4 and adding a second bridged RB1070. Note however that when the RA-840BX4 is bridged the speaker connected to it must have an impedance of 8 ohms or more. 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. [. . . ]