JBL 260 user manual Appendix

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Appendix

 

 

One thing that is critical to system setup is maximizing gain structure. Gain structure refers to aligning the gain of each device so that they all clip at the same point, and the noise floor of the entire system is at its absolute minimum. Quite often PA systems are setup with the amplifier input controls turned all the way up in the incorrect assumption that this is the only way to get the maximum output level. Amplifiers are fixed gain devices, turning down the amplifier input attenuators does not change the potential output of the amplifier; it only requires more input voltage to get full output power. Many amplifiers will clip with an input level greater than +6 dBu when the input attenuators are turned all the way up. Most mixing consoles can deliver over +18 dBu of output level before clipping. This means that with your amps tuned all the way up you are sacrificing 12 dB of headroom, resulting in poorer noise performance and the potential of system clipping. By adjusting the amplifier controls properly, you can maximize your system performance.

A way to set up your amplifiers for maximum gain structure is to use the clip indicators of the console and amplifiers themselves. Disconnect the output of the amplifier from the speakers. Run a continuous signal (pink noise or sine waves – many test CDs are available that have these types of signals) through your console. Turn up the output of the console until it begins clipping. If there is no clip indicator on the console then use the output meters; most reputable console manufacturers use red LEDs at the top of the meters to show the onset of clipping. Once the console is clipping, back the output gain down slightly until the clip indicator turns off. Run this signal through the DriveRack 260 and into the amplifiers with the crossovers and output gain section in the DriveRack 260 set for your particular speakers. Make sure that the output limiters are turned off. Run this signal into the amplifiers and turn up the input attenuators until the amplifier clip indicator begins to turn on. Turn the attenuators down slightly, so the clip indicator no longer is on. You have just maximized the gain through your system. This amplifier setting should give you maximum gain without clipping, another way of say this is that when the output of your console is clipping you will also be at the clip point of your amplifiers.

Once you have found the clip point of your amplifiers, you can mark this position and turn the amplifiers back up to the point where they are clipping. You can now use the output limiters in the DriveRack 260 to protect the amplifier from clipping no matter what you do at the console. With the amplifiers clipping, now go to the Limiter page of the DriveRack 260 and turn the limiter for each output band on. Make sure that the threshold is all the way up to +20dB. Now slowly reduce the threshold until the clip indicator of the amplifier turns off. You have successfully set the output limiter up and the amplifier will not be able to go into clipping no matter what the input is. You should now proceed to the next output band and go through the same process. If you are using a sine wave to create clipping in your amplifier you should make sure that the sine wave is within the frequency range of the output band that your are working with. Once all the limiters are set up you can now turn the amplifiers back down to the gain maximized position. The Wizard will automatically set your limiters based on your choice of amplifier. Because of component variances within the amplifier circuitry, you may need to adjust the limiter settings by a few dB after running the Wizard to ensure that they are set correctly. Once all the limiters are set up and the gain is maximized, reduce the output of your console and reconnect your speakers. Now for the fun part, sit back and send your favorite music through the system. If your system is not loud enough, you may want to consider an amplifier or amplifiers with greater output power. Most loudspeaker manufacturers recommend an amplifier that can provide 1.5 to 2 times the rated RMS power of the speaker. If this setting is too loud when your speakers are reconnected you can turn down the amplifier input attenuators even more.

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Contents DriveRack Important Safety Information Electromagnetic Compatibility Table of Contents DriveRackIntro Introduction DriveRack 260 FeaturesDefining the DriveRack 260 System Service Contact Info DriveRackIntroductionIntroductionDriveRack Warranty Section Getting Started Rear Panel Connections Getting Started Front Panel Getting Started Quick Start ConnectionsGetting Started Section DriveRack DriveRack DriveRack DriveRack DriveRack DriveRack Functions Editing Functions Basic Navigation Modes Effect Button Array OverviewEditing Functions Navigating the Pre-EQ -GEQ and PEQ Navigating the Crossover SectionEditing Functions Navigating the Other Section Navigating the Dynamics SectionEditing Functions Navigating the Delay Section Navigating the Utility/Meters SectionEditing Functions Navigating the Wizard Section Navigating the I/O SectionFunctions Navigating Factory Programs Configuration FunctionsProgram Definition Selecting ProgramsEditing Factory Programs Navigation ModesConfiguration Functions Saving Factory Program Changes Store Program ReplacingSelect Configuration Functions Creating a User ConfigurationSignal Path Link/UnlinkComp Select RouteSelect Link/Unlink Mono DLY 20 MS 810 ms Unused Select Link/UnlinkSaving Configuration Changes Route Name Output Ch2Detailed Detailed Parameters Pre-Crossover EQ 28 Band Graphic or 9-Band ParametricFeedback Eliminator Subharmonic Synthesizer Gate Detailed Parameters Automatic Gain Control AGC Crossover Detailed Parameters Notch FiltersPost-CROSSOVER PEQ Compressor/Limiter Gain G -20 to +20 dB Threshold T -40 to +20dBuRatio R 1.0 to Inf1 Auto On/OffHold 0 to 500 m Sec per band or global Limiter On/OffAttack .01 to 200 m Sec per band or global Release 360 to 5 dB / Sec per band or globalAlignment Delay Input RoutingOutput Meters LCD Contrast / Auto EQ Plot Utility LCD Contrast Auto EQ PlotUtilities/Meters PUP Program/MuteZC Setup Panel Power Up Modes PUP Program Stored PUP Mute CurrentZC Setup Output Panel ZC-2 BoostCut Panel 1 ZC-3 Select a No ChangeSet Security Level Pre EQ Low Panel ZC-4 Switch 1 2 3 No ChangeSecurity Password Edit High Password Edit Med Password Press Store to ChangeSet 260 Device Level High Password Enter PasswordProgram List/Program Change Prog Change Mode Program List Prog Lock Program ListZone Controllers Panel INS a Comp o+LIM 0+ Output Trims NetPage Control Remote Control DriveWare PC Software GUISection Basic Operation DriveRack Remote Control ZC-Zone Controllers Zone Controller InstallationZC-1 & ZC-2 Zone Controller Wiring Section Diagram a Diagram B Diagram C Guide Hardware Application GuideMono 4-Way w/ Two Aux Zones SoftwareApplication Guide Stereo Tri-amp Application Guide Stereo w/ four Aux Zones Application Guide Stereo Bi-amp w/ Dual Delay Page DriveRackAppendix Appendix Factory Reset Power Up Quick Key OptionsAppendix Specifications Analog InputsAppendix Auto EQ Optimization Tips Adjust Crossover Output Gains gain structureLook out for Modes Appendix Crossover Diagrams Main Speakers Power Amplifiers Appendix Program List/ Speaker Tunings/ Power Amp TuningsProgram List Appendix Block Diagram DriveRackAppendix aAppendix Input and Output Diagrams System Setup and Gain Structure Appendix Gain Level JumpersAppendix

260 specifications

The JBL 260 is a powerful and versatile loudspeaker that embodies the brand's renowned commitment to audio excellence. Known for its striking design and rich sound quality, the JBL 260 caters to both audiophiles and casual listeners alike, ensuring an immersive listening experience in any environment.

One of the standout features of the JBL 260 is its high-efficiency design, which allows it to deliver exceptional sound performance even in larger spaces. The speaker is equipped with a robust 6.5-inch woofer that provides deep, resonant bass, while a 1-inch soft dome tweeter ensures clear and detailed high frequencies. This combination results in a balanced sound signature that captures the subtle nuances of various music genres.

The JBL 260 employs advanced technologies such as Harman's proprietary Polished Surface Com Acoustic Design, which minimizes cabinet vibrations and resonances. This technology contributes to the overall clarity of the audio output, allowing for a more natural soundstage. Additionally, the Waveguide technology used in the speaker enhances the dispersion of sound throughout the room, ensuring that listeners can enjoy a consistent audio quality, regardless of their position.

Connectivity is another area where the JBL 260 excels. The speaker includes versatile connection options, such as Bluetooth, allowing users to stream music wirelessly from smartphones, tablets, or computers. This makes it incredibly easy to integrate the JBL 260 into modern home entertainment systems. With a range of inputs, including RCA and auxiliary ports, the speaker can accommodate various audio sources, making it a great choice for both casual listening and serious audio setups.

The design of the JBL 260 is both sleek and functional, with a modern aesthetic that fits seamlessly into any décor. Its sturdy construction not only contributes to its durability but also enhances sound quality by minimizing unwanted distortions. The speaker is available in various finishes, allowing users to choose a model that best suits their personal style.

In summary, the JBL 260 is a feature-rich loudspeaker that brings together advanced sound technologies, versatile connectivity options, and an attractive design. It stands out as an ideal choice for anyone seeking to elevate their audio experience, making it a solid investment for years to come.
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