JBL S4800 Owner's Manual

Contents

CHAPTER 5 – PLACEMENT AND SETUP CONSIDERATIONSThe S4800 loudspeaker system isdesigned to be less affected byroom acoustics than conventionalimaging systems. However, it isvery sensitive to overall symmetry,and proximity to walls, ceilings andcorners.Ideally, any listening room shouldcontain a combination of live sur-faces (e.g., walls and windows)and absorbent surfaces (e.g.,drapes, carpets, upholstery). Ifthe distance from floor to ceilingis short, it is preferable that onesurface has an absorbent cover-ing. With the S4800, it is mostimportant to be able to accommo-date the optimum listening areathat is defined by the 100° hori-zontal/60° vertical coveragepattern of the horn.The listener should be centered infront of the speakers, and furnitureshould be of an appropriate heightso that when the listener is sitting,his or her ears are level with thehorn (approximately 32 inches/80cm), as illustrated in Figure 2.CAUTION: The S4800 is a massivesystem comprising materials chosenfor their density, with its weightconcentrated in a relatively narrowarea. Verify the integrity of the floorsurface before placing and settingup the speakers. See FloorRequirements.If possible, the distance betweenthe speakers should be the sameas the distance between eachspeaker and the listening area.Angle the speaker in toward thelistener so that when seated, thelistener can look straight into thecenter of the speaker (Figure 7). Asthe distance increases betweenthe speakers, increase the inwardangle of the speaker.The imaging qualities enable thespeakers to be placed relatively farapart from each other. In addition,the low-frequency alignment fea-ture enables placing the speakersnear, or even in, a corner withoutproducing an overabundance ofbass. This corner placement abilityallows optimum performance evenin small rooms.The S4800 system can operatefairly close to the wall. Leaveenough clearance between theback of each speaker and the wallto allow for making the connec-tions on the back of the speaker(approximately 2 inches – 3 inchesis sufficient), and to avoid interfer-ence with the performance of thetuned port. Remember that thesespeakers weigh close to 143 lb(65kg) each and cannot be easilymoved.FLOOR REQUIREMENTSThe floor in the location selectedfor setting up the S4800 speakersmust be capable of supporting aload of 143 lb (65kg) per speaker.Because of the coupling effect ofthe stainless-steel feet, a flat, hardsurface such as wood or linoleumis preferable. However, the designof the loudspeaker’s coupling sys-tem, along with the speaker’sextreme weight, should result inexcellent performance on any sur-face, even on carpets.To prevent indentations on woodor linoleum floors caused by theweight of the loudspeaker, alwaysutilize the enclosed coasters.Do not set up the S4800 systemdirectly on a ceramic tile floor; theconcentrated weight might causethe tiles to crack.Figure 7. Room placement of S4800 speaker system.10