User manual HAFLER SE240

[. . . ] Cool air must be able to circulate freely through the perforations in the cover and under the chassis, and around the heat sinks. It is expected that the amplifier will always be resting on its feet, which should be on a hard enough surface that air flow underneath will not be obstructed. If the amplifier is mounted in a rack, or through a panel, the feet may be removed so long as adequate ventilation is provided through the bottom openings. It is normal for the cover and heat sinks to become warm in use. Location If the amplifier is to be installed close to a record player, you should first check its position for freedom from hum pickup by the phono cartridge, as any large power transformer radiates a field which may induce hum. [. . . ] Standard #18 gauge lamp cord Standard #18 gauge lamp cord (zip cord) is satisfactory for up to 15 feet if your speakers #16 are of 8 ohms or higher impedance. A heavier gauge (#16 or larger) wire should be used with 4 ohm speakers, or 8 ohm speakers at a greater distance. Special loudspeaker cables which have adequate thickness to accommodate long runs are usually available from audio dealers. The SE-240's red and black outputs accept standard banana banana plug connectors, including the double ones with 3/4" spacing. These are the most convenient to use if you will be disconnecting the speakers occasionally. The terminals will also clamp a spade lug, or a bare wire through the hole in the center post. Be sure there are no frayed wire ends which could touch adjacent terminals or the chassis. Consistent phase relationships are important when connecting speakers in order to enable full bass reproduction as well as mid-range and high frequency time alignment. To be sure all the speakers in a system are wired in phase to the amplifier, each ground or `-' speaker terminal should be connected to its black ground terminal on the SE-240, and the speaker's `+' terminal to the corresponding red binding post. Speaker connecting cable identifies one wire from the other by the color of the wire, or by marking or coloring the insulation. NOTE: In the special case of monophonic operation of the SE-240, described later, different speaker connections are employed. The black output terminals of the SE-240 are connected together internally and grounded to the chassis, This facilitates the use of external devices which use a common ground connection, such as some headphone junction boxes. You must be sure that the ground or shield connection from such a device goes to a black terminal on the SE-240. NOTE: No such connection may be made when the SE-240 is connected for bridged mono operation. 5 Conventional Stereo Connections It is best to make all connections with the SE-240 switched off. Each of the stereo speakers connects to one horizontal pair of red and black outputs, as identified left or right on back of the SE-240. The input signals connect to the corresponding input jacks, and the Mono/Stereo switch should be set to Stereo. Connections for Monophonic Operation When you wish to drive a single loudspeaker with increased power capability, the SE-240 can be operated in a bridged mode which drives both channels with the same signal and combines their output to deliver more than 350 watts into 8 ohms. In this arrangement, the speaker is connected only to the two red output terminals. The left red terminal is `+', and the right red terminal is the `-' connection. Set the Mono/Stereo switch to Mono, and connect the input signal to the left channel input only. Important Note: Never use a speaker with an impedance of less than 8 ohms when operating the SE-240 in the bridged mode; the increased current output could damage the amplifier. LOUDSPEAKER SELECTION AND PLACEMENT Normal Stereo The SE-240 is designed to deliver more than 120 watts of audio power into an 8 ohm load. [. . . ] In this case, check the surroundings of the unit to ensure sufficient air flow around the heatsinks and through the vent holes. Otherwise, check the load impedance connected to the outputs to see if it is far below 8 ohms. 7 Fuses The SE-240 is supplied with a 10 ampere Slo-Blo AC line fuse and four power supply fuses. If one of these fails, it is usually indicative of a fault which will require professional service. FACTORY SERVICE AND LIMITED WARRANTY If you have any difficulties or questions concerning your SE-240 amplifier, please call our Technical Service Department weekdays, 8 a. m. Should you have any doubts as to whether the amplifier is malfunctioning and requires service, please call us before sending in for repair. The Hafler SE-240 is warranted for 3 years from date of purchase, including parts, labor, and return shipping cost from the factory to owner within the continental U. S. [. . . ]