User manual ROTEL RSS-900

[. . . ] Keep the ventilation inlets on the unit unobstructed. For example, do not place the unit on a bed, sofa, rug, or similar surface that could block the ventilation slots. If the unit is placed in a bookcase or cabinet, there must be sufficient clearance around the unit and ventilation of the cabinet to allow proper cooling. Keep the unit away from radiators, heat registers, stoves, or any other appliance that produces heat. [. . . ] Save the RSS-900 shipping carton and all enclosed packing material for future use. Shipping or moving the RSS-900 in anything other than the original packing material may result in severe damage. Fill out and send in the owner's registration card packed with the RSS-900. Also be sure to keep the original sales receipt. It is your best record of the date of purchase, which you will need in the event warranty service is ever required. Note: The RSS-900 does not require AC power to operate. The RSS-900 is designed for use with amplifiers that can produce as much as 200 watts per channel. Note: Turn off the power to all the components in the system before you make any signal connections. NOTE: If speakers that have a minimum impedance of less than 4 ohms are connected to the RSS-900 the impedance the amplifiers receives may be less than 4 ohms. Check the instruction manual for your speakers for this information. If you are unsure about whether or not a certain combination of speakers can safely be used with the RSS-900 and your amplifier consult your authorized Rotel dealer. The polarity -- the positive/negative orientation -- for every connection between the amplifier and the RSS-900, and between the RSS-900 and the speakers, 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). Place the RSS-900 on a firm flat surface where it will be free from excessive dust, heat or cold, moisture or high humidity, or exposure to direct sunlight. Do not allow any foreign objects to fall into the ventilation holes of the RSS-900. Like many audio components that handle high-level signals, the RSS-900 produces some heat during normal operation. Do not place anything on top of the RSS-900 or allow the vent holes in the top of the cabinet to be blocked. [. . . ] Such problems are almost certainly the result of problems elsewhere in the system. In rare instances a loose strand of speaker wire that is barely touching the other wire or terminal can cause an intermittent crackling noise. This is easy to check and eliminate as a possible source of the problem. If one or both channels is not producing sound, check to see if other speaker outputs are functioning properly. [. . . ]