Atlas Sound XLT 8.3EQUALIZATION, 8.3.1HF-LevelSwitch, 8.3.2Equalization Tips, 8.4FINAL RESULTS

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8.3EQUALIZATION

Once volume level balances are set, you can then equalize the loudspeaker, if desired, using the loudspeaker’s HF Level switch and/or a graphic or parametric equalizer or tone controls on the mixer. Bear in mind that Community loudspeakers are optimized for good performance out-of-the-box in most typical PA applications and environments.

8.3.1HF-Level Switch

This two-position switch (FLAT and +4 dB), located on the input panel of the full-range loudspeakers, is used for adjusting the acoustic level of the high frequencies. Use this switch to voice the loudspeaker for different performers, types of program material, or acoustic environments. Here are some general suggestions for using it.

Use the FLAT position:

In reverberant (hard surfaced) rooms that over-accentuate high frequencies. For background music to make it less obtrusive to listeners.

When most listeners are close to the loudspeakers.

When feedback is a potential problem because microphones are close to the loudspeaker. Use the +4 dB position:

In noisy environments to cut through to the listener better. In absorptive environments that soak up high frequencies.

To project vocals and/or lead instruments over other back-line instruments. To better project high frequency sound over longer distances.

8.3.2Equalization Tips

Equalization should primarily be used to eliminate problem feedback frequencies or to adapt the system to different acoustic environments. You should not need more than a few dB of boost or cut equalization for any particular range of frequencies. The best equalization techniques involve cutting rather than boosting frequencies.

Equalizing the loudspeakers may not provide good results if this is done while listening at a close distance or in an acoustical environment significantly different from where the loudspeakers will be used.

Our hearing is much more tolerant of dips than it is of peaks in the frequency response of an audio system. Therefore, reducing a peak is more important than filling a hole in the frequency response.

Equalization boosts can easily cause overloads and clipping in the electronic signal chain. They also create peaks in the frequency response that can dramatically reduce gain before feedback when using microphones. By contrast, cutting specific frequencies, even a couple of dB, can often dramatically improve gain before feedback.

The equalization for the individual input channels on a mixer is very effective to use as these adapt the sound of each input to the loudspeaker. Overall equalization changes the sound of the loudspeaker for all inputs.

The power handling of loudspeakers is lowest at their extreme low and high frequencies. This is also where they are producing less output leading to a temptation to apply EQ boosts at those points. Doing this can compromise the power handling of the loudspeaker. In addition, it does little good for the performance or the reliability of a loudspeaker to boost frequencies that are beyond the specified operating range of the loudspeaker.

8.4FINAL RESULTS

Once the above procedures are followed, your loudspeaker should reproduce audio cleanly, clearly and with all frequencies in good balance. Noise should not be audible and you should be able to drive the amplifier to its maximum output on normal program material with no significant distortion or other undesirable sounds.

PAGE 31 Community XLT / XLTE Series Owner’s Manual

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Contents FULL-RANGESYSTEMS AND SUBWOOFERS XLT / XLTEPage COMMUNITY PROFESSIONAL LOUDSPEAKERS DIN EN 55013 08-1991 DIN EN EC STATEMENT OF CONFORMITYDIN EN Community Light & Sound, Inc. 333 East 5th StreetDIAGRAMS and TABLES TABLE OF CONTENTSCHAPTER PAGE1.3IMPORTANT SAFETY INFORMATION 1 INTRODUCTION1.2MODEL NUMBER USAGE IN THIS MANUAL 2 UNPACKING AND INSPECTION Page Page Figure 1 Physical Features 3.1FEATURES MATRIX 3 PHYSICAL FEATURES See FIGURETable 1 Physical Features Matrix 3.2FEATURES DESCRIPTIONSPhillips pan-head screws Footnotes for Physical FeaturesTable 2 Product Listing 4.3DRIVERS 4.1ABBREVIATED OPERATING INSTRUCTIONS4.3.1High Frequency Driver 4.3.2Mid Frequency Driver 46 models only4.6.2HF-LevelSwitch 4.6.1PASSIVE / BIAMP Switch4.3.4Ferrofluid Cooling 4.4PATTERN CONTROL HORNS4.6.5PowerSense Indicators 4.6.4PowerSense DDP Circuit4.7POWER HANDLING 4.6.3Subwoofer Full-RangeOutput4.8.2Corner Protectors and Stacking XLT only 4.8.1Permanent Mounting4.8.3Feet XLTE only 4.8.4Carrying Handles4.9.1Community Accessories 4.9OPTIONAL ACCESSORIES4.9.23rd Party Accessories 4.8.641 Positioning and Horn Rotation5 SETUP AND OPERATION 5.1CHOOSING A POWER AMPLIFIER5.1.2Power Amplifier Load Impedance Table 5 Recommended Amplifier Power for Subwoofer FIGURE 2 PASSIVE Mode Configurations FIGURE 3 BIAMP Mode Configurations 6.1.1Loudspeaker Wire Gauge 6 ELECTRICAL INSTALLATIONTable 6 Loudspeaker Wire Gauge Selection 6.1LOUDSPEAKER CABLE6.3.1Parallel Connector Wiring 6.2.2Internal Input Jack Wiring6.3.2Load Impedance When Paralleling Loudspeakers 6.2.1Choosing an Input Jack6.4CONNECTING THE LOUDSPEAKERS 6.4.1PASSIVE Mode Wiring See FIGUREFIGURE 4: Wiring for PASSIVE Mode Full-Range FIGURE 5 Wiring for BIAMP Mode Full-Range 6.4.2BIAMP Mode Wiring See FIGUREFIGURE 6 Wiring for Subwoofer 6.4.3Subwoofers See FIGURE7.1.1Removing and Re-installingthe Grille 7 PHYSICAL INSTALLATION7.1FRONT GRILLE 7.1.2Custom Grille Cloth7.3.2Model 42 and 7.3.1Model 41 Horn Orientation7.4MOUNTING AND RIGGING IMPORTANT NOTE Mounting/Rigging Point HolesFIGURE 7 Mounting Point Detail - Pull Direction 7.4.2Using the Community CSSUPKIT Suspension KitFIGURE 8 XLT Mounting Points DANGER7.4.4Stand Bracket Inserts 46 and 48 only 7.4.3Using the Community WB1 Mounting AccessoryDANGER See FIGURE FIGURE 9 XLTE Mounting / Rigging Points7.5.1Using the Community EYBLTKIT FIGURE 10 XLTE Mounting / Rigging Point Detail7.6STACKING ENCLOSURES 8.1INITIAL TESTING 8 ACOUSTICAL ADJUSTMENTS8.2FINAL ADJUSTMENTS 8.2.1Electronic Gain Structure8.2.2Residual Noise 8.2.3Volume Level Balancing8.3EQUALIZATION 8.3.1HF-LevelSwitch8.3.2Equalization Tips 8.4FINAL RESULTS9.1POWERSENSE DDP 9 OPERATING PRECAUTIONS9.1.1Operating Modes and PowerSense DDP 9.1.2PowerSense DDP Circuit OperationFIGURE 11 Amplifier Clipping 9.3ACOUSTIC VOLUME LEVEL PRECAUTIONSFIGURE 12 Sound Exposure Limits 9.4TESTING AND TEST SIGNALS10 SERVICING THE LOUDSPEAKER 10.1ACCESSING THE DRIVERS10.1.1LF Drivers 10.1.2MF and HF Drivers11.1FULL-RANGEMODELS 11 TECHNICAL SPECIFICATIONS11.2MONITOR SPEAKERS AND SUBWOOFERS 12 IN CASE OF DIFFICULTY No bass No high frequencies Transferable Limited Warranty 13WARRANTY INFORMATION AND SERVICE9907007F C. Specifications Table 8 Additional Model SpecificationsAPPENDIX - XLT41E and XLT48E A. XLT41E and XLT48E Additional ModelsINDEX Page Page Page Page Page 333 East 5th Street, Chester, PA Phone 610 876-3400Fax1999 Community Light & Sound, Inc. 991015Cm