Produttore : Altec Lansing
File Size : 187.17 kb
File Nome : aa270198-d733-48db-9030-15c1efdde151.pdf
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Facilità d'uso
This cabinet is sealed at the factory; do not attempt to take it apart or remove the back panel. 2. Turn the cabinet so the short side without fiberglass lining is up; drill a hole in the top, avoiding the diagnonal brace. This hole should be just large enough to pass four wires through. 3. The interconnecting wires are packed Locate the four longest wires (one red wire, one green wire, two black wires). 4. Unpack the two 3156 LF loudspeakers. Attach a green and black wire to the terminals of one loudspeaker. See Figure 2. 5. Lay the 8256X cabinet on its back panel. Mount one 3156 loudspeaker in one baffle opening of the cabinet; attach the loudspeaker with eight screws packed with the loudspeaker. Note that the flange of the loudspeaker is outside the cabinet, with the frame and magnet structure protruding into the cabinet. 6. Route the green and black wires of the loudspeaker through the opposite baffle opening; attach the wires to the second 3156 loudspeaker. Also attach red and black wires to the terminals of the second loudspeaker as shown in Figure 2. Feed the attached red and black wires through the hole drilled in the top of the cabinet (Step 2) or through one of the bass reflex ports; install the second loudspeaker in the remaining baffle opening and secure it with the eight screws packed with the loudspeaker. 7. Lift the cabinet upright and place it in the position it will occupy. 8. Unpack the two brackets and driver cradle from the hardware kit. Assemble them with two bolts, two lockwashers and two 7/16" nuts. See Figure 1. Set the assembly on top of the cabinet, approximately centered with the driver cradle toward the rear of the cabinet. 9. Upack the 288-8K HF driver and the HF horn (MRII564, MRII594, or MRII5124). Place the gasket packed with the 288-8K around its sound exit hole; install the 288-8K on the horn, securing it with the three lockwashers and 9/16" nuts provided. 10. Engage the lip flange of the horn in the two ears of the mounting brackets and swing the driver down into the cradle. - CAUTION- The magnet will pull the cradle toward the driver as it is lowered into position. 11. Attach the short black and white wires packed with the N1285-8A network to the terminals on the 288-8K. It will be necessary to remove one pair of crimp connectors from these wires and replace them with those packed with the 288-8K. 12. Place the N1285-8A on top of the cabinet, facing left or right; if the speaker wires are routed through a port in the baffle, put the N1285-8A on the same side. 13. Set the frequency switch of the N1285-8A to 500 Hz or 800 Hz. Wire the N1285-8A according to Figure 2. 14. If the amplifier to be used cannot safely drive a 5-ohm load, wire the system as shown in Figure 3, using a 15067 autoformer. 15. If you wish to attach the N1285-8A to the cabinet, let the front panel of the network hang over the side of the cabinet; drill or punch twao pilot holes and install two wood screws to secure the network. 16. Decide how much power loss is acceptable in the line between the amplifier and the loudspeaker; select a wire gauge according to Altec Lansing Technical Letter 265A. Attach the wires to the input terminals of the N1285-8A network. 17. Adjust the tilt of the HF horn for greatest uniformity of direct sound in the audience area; loosen the nuts and raise or lower the driver cradle as necessary; retighten nuts. 18. Operate the loudspeaker and adjust the H.F. LEVEL control on the N1285-8A until the best spectral balance is achieved. 19. If there is sufficient front-to-back clearance around the loudspeaker, adjust phasing of the drivers according to Altec Lansing Applications Note 9. This will require the front lip of the HF horn to overhang the front edge of the cabinet about 7". 20. After locating the horn position, mark location of the four holes in the mounting brackets; drill or punch pilot holes in the cabinet for the four wood screws provided in the hardware kit. 21. If it becomes necessary to replace the diaphragm/voice coil assembly in the 288-8K driver, use a 23763 diaphragm; follow service instructions in Altec Lansing publication 42-02-035593. -NOTE- Do not drill this hole if the loudspeaker is to be installed behind the screen in a motion picture theatre. ALTTEC LANSING0 Specifications and components subjcct to change vnthout notice. Overall performance will be maintained or improved. 10500 W. Reno Ave., Oklahoma City, OK 73126 a MARK IV company 42-02-035639 • 42-07-035639 REVISION 2 LITHO IN U.S.A. 1091-1.7M ALTEC LANSING CORPORATION 22. If it becomes necessary to recone the 3156 loudspeakers, use a R3156 recone kit; follow service instructions in Altec Lansing publication 42-02-035594. 23. If it becomes necessary to repair the 8256X cabinet, construction plans are given in Altec Lansing Applications Note 12. WHITE Individual copies of this and all Altec Lansing publications are available without charge from Altec Lansing, Box 26105...