Atlas Sound XLTE owner manual 8.2.2Residual Noise, 8.2.3Volume Level Balancing

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WARNING:

Before setting gain structure, disconnect the loudspeaker(s) from the amplifier(s).

2.The basic procedure is to use a test signal and set the first piece of equipment in the signal chain (usually the mixer) so it is just below its maximum voltage output from its specifications as read on the voltmeter, or on equipment’s output meter, or just below clipping as observed on the oscilloscope, or just starting to audibly distort. Without changing the volume of the test signal or mixer, adjust the volume level control on each piece of equipment following, including the power amplifiers, so that each is just below its maximum output. If everything is set properly, you will find that the input volume level controls on the power amplifier will end up being set at something other than maximum. This is normal for a well gain-structured system.

Notes:

A.Due to differences in the capabilities of equipment in the signal chain, it may not be possible to get results exactly as stated.

B.For each device, make sure it is the output and not the input that is clipping.

C.If you are in doubt about this procedure, a good compromise is to set all devices in the signal chain to their 0 dB gain (also called ‘unity gain’) position on the input and output level controls. Then adjust your amplifier input level controls to reduce any residual noise to tolerable levels (See SECTION 8.2.2).

3.Remove the test signal, turn off all equipment, and reconnect the loudspeaker(s). The system is now ready for volume level balancing, assuming you have more than one loudspeaker. If you have only one loudspeaker or a left/right stereo configuration, the system should be ready for use.

8.2.2Residual Noise

XLT and XLTE loudspeakers have high sensitivities. This means that they produce a relatively high volume of sound for a given electrical input. This also includes the residual electronic noise of an audio system. By setting gain structure properly and using high quality, professional electronics with balanced connections, this noise should be at or near inaudibility. Even if less expensive equipment is used, the general quality of today’s electronics should result in a quiet system if the gain structure is set correctly. If residual noise is a problem, gain structure is the culprit - not the loudspeakers. The exception is humming or buzzing. This is usually a problem with ground loops in the system's electronic wiring, particularly with unbalanced equipment. Correcting this type of problem is beyond the scope of this manual.

8.2.3Volume Level Balancing

NOTE: If you are simply using one full-range loudspeaker or a simple left/right setup, this step can be skipped.

IMPORTANT: For these adjustments, you want to maintain the system’s dynamic range that was maximized by setting the gain structure. Therefore, DO NOT TURN UP THE INPUT VOLUME CONTROLS OF ANY OF THE AMPLIFIERS. For example, if you decide that a subwoofer is not loud enough, do not turn up the input volume control of its amplifier. Instead, turn down the input volume control of the amplifier for the full-range loudspeaker.

Once the system gain structure is set, you can adjust the volume level balances. This may mean balancing the volume levels between: HF and LF sections of a loudspeaker in BIAMP mode, a full-range loudspeaker to a subwoofer, multiple loudspeakers, or between main and delayed loudspeaker arrays. The idea is to make the system sound the best it can without using any equalization. This may also be done using acoustic test equipment such as an RTA (real-time analyzer), TEF™ analyzer, or something similar. Always determine the final volume level balance by listening to a variety of known program material. Balancing can also be done entirely by ear if acoustic test equipment is not available. In any case, the preferred method of adjusting volume levels for balancing loudspeakers is to make adjustments using the input level controls (also called sensitivity controls) on the amplifier(s). Alternately if the system has one or more electronic crossovers, their output level controls can be used.

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Contents XLT / XLTE FULL-RANGESYSTEMS AND SUBWOOFERSPage COMMUNITY PROFESSIONAL LOUDSPEAKERS EC STATEMENT OF CONFORMITY DIN EN 55013 08-1991 DIN ENDIN EN Community Light & Sound, Inc. 333 East 5th StreetTABLE OF CONTENTS DIAGRAMS and TABLESCHAPTER PAGE1.2MODEL NUMBER USAGE IN THIS MANUAL 1.3IMPORTANT SAFETY INFORMATION1 INTRODUCTION 2 UNPACKING AND INSPECTION Page Page Figure 1 Physical Features 3 PHYSICAL FEATURES See FIGURE 3.1FEATURES MATRIXTable 1 Physical Features Matrix 3.2FEATURES DESCRIPTIONSFootnotes for Physical Features Phillips pan-head screws4.1ABBREVIATED OPERATING INSTRUCTIONS Table 2 Product Listing 4.3DRIVERS4.3.1High Frequency Driver 4.3.2Mid Frequency Driver 46 models only4.6.1PASSIVE / BIAMP Switch 4.6.2HF-LevelSwitch4.3.4Ferrofluid Cooling 4.4PATTERN CONTROL HORNS4.6.4PowerSense DDP Circuit 4.6.5PowerSense Indicators4.7POWER HANDLING 4.6.3Subwoofer Full-RangeOutput4.8.1Permanent Mounting 4.8.2Corner Protectors and Stacking XLT only4.8.3Feet XLTE only 4.8.4Carrying Handles4.9OPTIONAL ACCESSORIES 4.9.1Community Accessories4.9.23rd Party Accessories 4.8.641 Positioning and Horn Rotation5.1.2Power Amplifier Load Impedance 5 SETUP AND OPERATION5.1CHOOSING A POWER AMPLIFIER Table 5 Recommended Amplifier Power for Subwoofer FIGURE 2 PASSIVE Mode Configurations FIGURE 3 BIAMP Mode Configurations 6 ELECTRICAL INSTALLATION 6.1.1Loudspeaker Wire GaugeTable 6 Loudspeaker Wire Gauge Selection 6.1LOUDSPEAKER CABLE6.2.2Internal Input Jack Wiring 6.3.1Parallel Connector Wiring6.3.2Load Impedance When Paralleling Loudspeakers 6.2.1Choosing an Input JackFIGURE 4: Wiring for PASSIVE Mode Full-Range 6.4CONNECTING THE LOUDSPEAKERS6.4.1PASSIVE Mode Wiring See FIGURE 6.4.2BIAMP Mode Wiring See FIGURE FIGURE 5 Wiring for BIAMP Mode Full-RangeFIGURE 6 Wiring for Subwoofer 6.4.3Subwoofers See FIGURE7 PHYSICAL INSTALLATION 7.1.1Removing and Re-installingthe Grille7.1FRONT GRILLE 7.1.2Custom Grille Cloth7.3.1Model 41 Horn Orientation 7.3.2Model 42 and7.4MOUNTING AND RIGGING IMPORTANT NOTE Mounting/Rigging Point Holes7.4.2Using the Community CSSUPKIT Suspension Kit FIGURE 7 Mounting Point Detail - Pull DirectionFIGURE 8 XLT Mounting Points DANGER7.4.3Using the Community WB1 Mounting Accessory 7.4.4Stand Bracket Inserts 46 and 48 onlyDANGER See FIGURE FIGURE 9 XLTE Mounting / Rigging Points7.6STACKING ENCLOSURES 7.5.1Using the Community EYBLTKITFIGURE 10 XLTE Mounting / Rigging Point Detail 8 ACOUSTICAL ADJUSTMENTS 8.1INITIAL TESTING8.2FINAL ADJUSTMENTS 8.2.1Electronic Gain Structure8.2.3Volume Level Balancing 8.2.2Residual Noise8.3.1HF-LevelSwitch 8.3EQUALIZATION8.3.2Equalization Tips 8.4FINAL RESULTS9 OPERATING PRECAUTIONS 9.1POWERSENSE DDP9.1.1Operating Modes and PowerSense DDP 9.1.2PowerSense DDP Circuit Operation9.3ACOUSTIC VOLUME LEVEL PRECAUTIONS FIGURE 11 Amplifier Clipping9.4TESTING AND TEST SIGNALS FIGURE 12 Sound Exposure Limits10.1ACCESSING THE DRIVERS 10 SERVICING THE LOUDSPEAKER10.1.1LF Drivers 10.1.2MF and HF Drivers11 TECHNICAL SPECIFICATIONS 11.1FULL-RANGEMODELS11.2MONITOR SPEAKERS AND SUBWOOFERS 12 IN CASE OF DIFFICULTY No bass No high frequencies 13WARRANTY INFORMATION AND SERVICE Transferable Limited Warranty9907007F Table 8 Additional Model Specifications C. SpecificationsAPPENDIX - XLT41E and XLT48E A. XLT41E and XLT48E Additional ModelsINDEX Page Page Page Page Page 1999 Community Light & Sound, Inc. 991015Cm 333 East 5th Street, Chester, PAPhone 610 876-3400Fax
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