JBL S4VC, S4HC, S4Ai, S4HC &S4Ai manual STANDING-WAVE Solutions Room Equalization

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FINE-TUNING YOUR AUDIO SYSTEM

Standing-wave energy tends to be concentrated in the corners of rooms, which is why placing a subwoofer in the cor- ner tends to increase its bass output. Because of this, it is possible to break standing waves up somewhat by “break- ing up” the corner. This can be accomplished by placing a column of thick, absorptive materials in the corners (covered by acoustically transparent cloth, of course). The column ought to be at least a foot on a side, and run from floor to ceiling. A variation of this is to run an absorptive panel diagonally across the corner, leaving open air space behind it. Both of these techniques are easily tried and sometimes quite effective.

STANDING-WAVE SOLUTIONS: ROOM EQUALIZATION

If a room exhibits severe standing-wave problems, the best solution is to know your own limitations; hire a trained acoustician. These professionals have the necessary background to analyze the various room modes and recommend appropriate action. This will sometimes take the form of a custom-designed bass trap, which may be easily con- structed. But it takes specific skills to determine its optimal design.

In other cases, careful analysis and parametric equalization may be appropriate. Optimize everything else that you can, then use EQ, if necessary, to “touch up” the room. This is its best use. Parametric equalization must be applied with care and a light touch to obtain optimal results. Professionals use it all the time, with excellent results – because they know its limitations and how to apply it.

Never equalize a room by ear. Room analysis is not as straightforward as it may seem. The analysis should be done using equipment with at least one-third-octave resolution, using both spatial and temporal averaging.

In any event, rooms requiring this level of treatment are relatively rare, and the skills necessary to handle them prop- erly are highly specialized. Do not hesitate to use the professional services of an acoustician when you need them.

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Contents S4VC, S4HC & S4Ai Contents Introduction Included Speaker Placement Center Channel SpeakersPlacement of the surround speakers remains critical Channel SystemsS4Ai Wiring Guide S4Ai Modes of OperationBipole Mode is Typically Used When Room is highly reflectiveOUT position see . See Table on the right sideSide Left Rear LeftMounting the Speakers Center studs. For horizontal mounting, cross-bracing isFace see . To flush-mount the grille to the wall SPEAKER-MOUNTING OptionsMounting the S4VC speaker using the S4PCB kit Requirements for MountingMounting S4VC speaker using the S4RFB kit Connecting the Speakers to the Rest of Your System Preparing the Hookup WireRoom Reflections FINE-TUNING Your Audio SystemAcoustical Problems in Listening Rooms See Figure However, since it is not possible toMaterials can be found with a small Excessive USE of Absorptive MaterialsRoom Absorption for Home Theater Systems Slap Echoes Background Noise Piece of cloth can be placed under offending knickknacks Rattles BACKGROUND-NOISE Solutions Standing WavesSTANDING-WAVE Solutions Room Ratios STANDING-WAVE Solutions Speaker PlacementSTANDING-WAVE Solutions Absorption An even distribution of them, so that theirSTANDING-WAVE Solutions Room Equalization Troubleshooting Troubleshooting Specifications S4VC S4HCJBL Consumer Products Crossways Park Drive Woodbury, NY