User manual NAD S250

[. . . ] Do not use this unit near water; for example, near a bath tub, washbowl, kitchen sink, laundry tub, in a wet basement or near a swimming pool. The unit should be installed so that its location or position does not interfere with its proper ventilation. For example, it should not be situated on a bed, sofa, rug or similar surface that may block the ventilation openings; or placed in a built-in installation, such as a bookcase or cabinet, that may impede the flow of air through its ventilation openings. The unit should be situated from heat sources such as radiators, heat registers, stoves or other devices (including amplifiers) that produce heat. [. . . ] Once all signal connections have been completed, turn down all the system's main volume control before turning the system components on. Then increase the volume control setting carefully to avoid damage to the system components. Read and follow all the safety instructions on the first page of this manual. To prevent a fire or shock hazard, do not place the amplifier where it will be exposed to any water or moisture. If liquid accidentally gets into the amplifier, immediately unplug the AC power cord. Do not operate the amplifier again until it has been examined by a service technician. the amplifier generates a moderate amount of heat , requiring ventilation. Do not place the amplifier in an enclosed area, such as in a bookcase or in a cabinet, unless it is very well ventilated. Be sure there is adequate room behind the amplifier for signal input and speaker output connections. If you want to locate the amplifier on a carpeted floor, place a board under it in order to prevent it from sinking into the carpet, blocking the air inlets on the bottom. Do not place the amplifier where it will be exposed to direct sun light for prolonged periods of time. NOTE: The amplifier's weight must always rest on its bottom feet. Never put the amp down on its rear panel, with its front panel facing up. The power transformer in the S250 generates a magnetic hum field of moderate strength. Turntables (especially those with a moving-coil pickup cartridge) should not be located near the amplifier. Magnetic media, such as audio or video tapes and computer diskettes, should not be stored near the amplifier. The NAD S250 houses five individual amplifiers, each on separate circuit board. Each amplifier channel acts as a "mono block" within the chassis. each input connector , and set of loudspeaker output terminals , is directly connected to that channel's circuit board. furthermore , this modular design increases reliability and thermal efficiency. The input circuit uses a totally new dual differential input topology that operates in true Class-A mode. The special HolmgrenTM toroidal transformer has less hum and magnetic leakage than conventional toroidal transformers, but retains the usual benefits of high efficiency and high power-to-weight ratio. [. . . ] If this occurs, switch the amplifier off immediately and check as indicated above for correct connection and/or heat build-up. The Power LED located just above the power button and Protection LED will light up. After a few seconds, the Protection LED will turn off, indicating that the amplifier is ready for use. The S250 can also be remotely switched from On to Stand-by and vice-versa using the 12V-trigger input on the back panel. [. . . ]