Crown Audio I-Tech Series Input Signal Compressor/Limiter, Average Power Limiter, Clip Eliminator

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I-Tech Series Power Amplifiers

4 Advanced Operation

4.6.14 Input Signal Compressor/Limiter

An input signal compressor/limiter is available for each channel. Five parameters control this feature:

Enable: Enables or disables this function.

Threshold: Sets the level, in dBu, above which the compressor begins to attenuate the input signal. This level corresponds to the input level meter reading. The compressor is “feed-forward,” meaning that the level detection point is located before the gain control stage. The range is from +20 dBu to – 50 dBu.

Hysteresis: A “dead zone” that ensures a significant change before acting. The range is from 0 to 12 dB. It requires the signal to go above the upper threshold before engaging and to go below the lower thresh- old before releasing. Not available in System Architect.

Attack Time: Sets the attack time of the compressor. The attack time is defined as the time it takes the compressor to attenuate the signal gain by 20 dB. The range is from 1 millisecond to 0.1 second.

Release Time: Sets the release time of the compressor. The release time is defined as the time it takes the compressor to increase the sig- nal gain by 20 dB. The range is from 10 milliseconds to 10 seconds.

Compression Ratio: Sets the compression ratio of the compressor. The ratio is the relation between the amount of attenuation applied by the compressor verses the amount that the input signal is over the threshold. The available settings are 2:1 to 32:1.

Beyond the three controls for each channel, a single-control Com- pressor Tie connects the compressors together. The compressors are tied at their sense points, meaning that the greater of the two input signals will be used as stimulus for both compressors. Each compres- sor will still compress based on its individual threshold, attack, release and ratio settings. Not available in System Architect.

4.6.15 Peak Voltage Limiter

This limits the peak voltage output of the amplifier. Four parameters control this limiter for each channel:

Enable: Enables or disables this function.

Threshold: Sets the level, in absolute voltage, which the limiter will allow from the amplifier. The range is from 12 Vpk to 255 Vpk.

Attack Time: Sets the attack time of the limiter. The attack time is defined as the time it takes the limiter to attenuate the output signal by 20 dB. The range is from 1 millisecond to 100 milliseconds.

Release Time: Sets the release time of the compressor. The release time is defined as the time it takes the limiter to increase the output signal by 20 dB. The range is from 10 milliseconds to 10 seconds.

4.6.16 Average Power Limiter

This limits the long-term output power of the amplifier. Four parame- ters control this limiter for each channel:

Enable: Enables or disables this limiter.

Threshold: Sets the average power level, in watts, which the limiter will allow from the amplifier channel. The range is from 10 watts to 10,000 watts. This level should be set to the connected loudspeaker’s long-term power rating. Also you must enter the loudspeaker’s nomi- nal impedance.

Attack Time: Sets the attack time of the limiter. The attack time is defined as the time it takes the limiter to attenuate the output signal by 20 dB. The range is from 1 second to 30 seconds.

Release Time: Sets the release time of the compressor. The release time is defined as the time it takes the limiter to increase the output signal by 20 dB. The range is from 1 second to 30 seconds.

4.6.17 Clip Eliminator

This limiter monitors the clip events and attenuates the input signal to prevent amplifier clipping. The attack and release times are preset to optimum rates. Only one parameter controls this limiter. “Enable” enables or disables this limiter.

4.6.18Limiter Tie (not available in System Archi-

tect)

This control forces both channels to track by using the greatest (worst case) attenuation of any limiter from either channel. With this option disabled, each channel will independently take the greatest attenuation of its own four limiters (voltage, power, clip, thermal) and ignore the limiting of the other channel. Note that this function does not include the effects of the input compressors. To tie the input compressors, use the Compressor Tie function.

4.6.19 Load Supervision

The load supervision feature allows real-time monitoring of the load connected to each amplifier channel. When enabled, the I-Tech contin- uously monitors the amplifier output voltage and current, and calcu- lates the long-term average load impedance. The measured load impedance is compared against the user-defined high and low limits. If either limit is exceeded, the status indicator and, if enabled, the IQwic Error Reporting functions alert the user of the problem. There are six controls and two indicators for each channel:

Enable: Enables or disables the load-supervision function.

High Limit: Sets the upper bound above which the system will report a “high” error status.

Low Limit: Sets the lower bound below which the system will report a “low” error status.

Nominal Load Impedance: Sets the expected average impedance for the connected load. This value determines the output signal level required for the test. This parameter is also used by the average power limiter to determine the expected power threshold. (See Section 4.6.16).

Report Error to Network: Enables Error Reporting to send an error report via the network so that high and low load conditions are reported to the IQ software.

Test Indicator: This indicator is active when the amplifier output sig- nal is sufficient to allow load impedance calculation and test verifica- tion.

Low/Normal/High Indicator: This indicator shows the present sta- tus of the load impedance with respect to the user-defined high and low limits.

Z Average Monitor: Reports the actual calculated average load impedance in ohms. Its range is from 0 ohms to 250 ohms.

4.6.20 Memory Backup Configuration

In normal operation, the I-Tech amplifier stores all its settings in non- volatile memory. When the power is removed from the amplifier and then restored, the amplifier uses these backed-up settings for its func- tions. This feature can be disabled with the memory backup enable

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Operation Manual

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Contents 137289-10 T4000 T6000 T8000Some models may be exported under the name Amcron 11/07Important Safety Instructions Importantes Instructions de SécuritéFamily Name I-Tech Safety StandardEuropean Representatives Name and Address EMC StandardsFor bridge-mono operation, see Quick-Start Guide Stereo WiringGetting Started With I-Tech Quick-Start Guide Bridge-Mono Wiring Figure A.5 Rear Panel Connections for Bridge-Mono WiringTable of Contents Analog and digital thru connectors FeaturesHigh power density, up to 8000 watts in a 2U chassis How to Use This ManualSetup Unpack and Install Your AmplifierConnecting to AC Mains Wire Inputs and Outputs Wiring basicsDistance Choose Input Wire and ConnectorsChoose Output Wire and Connectors Stereo Mode Wiring Important Turn off the amplifier and unplug its power cordBridge-Mono Mode Reach maximum attenuationOperation Startup ProcedurePrecautions Protecting Your SpeakersFront Panel Controls and Indicators Cooling Vents Back Panel Controls, Indica- tors and Connectors Fans Advanced Operation Table of Contents Advanced OperationMute/Unmute Navigating the LCD Control Screen IntroductionAttenuation and Bar Meters Front Panel LockoutMenu/Exit Prev Prev CH1 LF-1&2 CH2 LF-3&4OFF v Digital DIG Analog AnlgOFF 114 Menu Tree Operation ExamplesPress Menu/Exit Operation Example Downloadable Presets Presets IntroductionUser Presets Digital Audio Options AES/EBUSelect Network Card Network Setup WizardFix Errors Individually Address Devices on the NetworkSignal Mute Input Signal Level MonitorPower/ Standby Control Error ReportingMemory Backup Configuration Input Signal Compressor/LimiterAverage Power Limiter Clip EliminatorFilters Input Signal RouterDelay Latency Noise GeneratorRated range TroubleshootingAmplifier’s Power switch is off Ethernet link is broken Input signal level is very lowSpeakers not connected Open circuit due to speaker failure Hz 20 kHz with 0.35% THD SpecificationsPerformance Latency digital inputsAC Line Connector Crosstalk below rated power, 20 Hz to 1 kHzCommon Mode Rejection CMR 20 Hz to 1 kHz DimensionsCharts Typical Frequency Response 1WT4000 AC Power Draw and Thermal DissipationTech 4000 AC Current Draw and Thermal Dissipation Tech 6000 AC Current Draw and Thermal Dissipation T6000Tech 8000 AC Current Draw and Thermal Dissipation T8000Advanced Features TCP/IQ and HiQnet audio networks offer many advantages Appendix a Network BasicsTCP/IQ and HiQnet Networks 00-0A-40-00-DC-2F Network AddressesLet’s explain each identifier 192.168.0.1Appendix B Setting Sensitivity for Best Gain Staging Service Warranty United States & CanadaWorldwide Except USA & Canada Product purchased from *Business/Individual Country Crown Audio, IncFax This page Intentionally Left Blank Crown Audio Factory Service Information This page Intentionally Left Blank This page Intentionally Left Blank

I-Tech Series specifications

The Crown Audio I-Tech Series represents a pinnacle of power amplification technology, designed to meet the demanding needs of live sound reinforcement and installation applications. Renowned for their flexibility, efficiency, and sound quality, these amplifiers integrate cutting-edge features that appeal to both professional audio engineers and musicians alike.

One of the key technologies employed in the I-Tech Series is the use of DriveCore technology. This innovative design allows the amplifiers to achieve high power output while minimizing size and weight. The DriveCore technology combines the efficiency of Class D amplification with superior sound quality, yielding a lightweight solution that maintains high fidelity and low distortion even at peak volumes.

The I-Tech Series amplifiers come equipped with a comprehensive suite of digital signal processing (DSP) capabilities. Each amplifier integrates sophisticated DSP algorithms that enable advanced speaker management, including extensive equalization, delay settings, and limiting controls. This ensures optimal performance for a variety of loudspeakers and installation scenarios, allowing users to tailor the output to the specific acoustical environment.

Connectivity is another strong point for the I-Tech Series. The amplifiers often include a variety of input options, providing flexibility for different setups, whether analog or digital. The inclusion of Ethercon connectivity enables seamless integration into a networked environment, allowing for remote control and monitoring via Crown's sophisticated software interface. Users can access real-time data about the system's performance, making adjustments on-the-fly to maintain optimal sound quality.

Durability and reliability are fundamental characteristics of the Crown I-Tech amplifiers. Built to withstand the rigors of touring and the demands of permanent installations, these amplifiers are housed in rugged enclosures that dissipate heat effectively while maintaining a compact form factor. Integrated protection circuits safeguard against over-temperature, over-current, and short-circuits, ensuring longevity even under extreme conditions.

In terms of power output, the I-Tech Series features a range of models, each capable of delivering substantial wattage to drive large sound systems with authority. The efficient cooling design allows for extended use without compromising performance, making them suitable for both large concerts and smaller venues.

In summary, the Crown Audio I-Tech Series amplifiers combine advanced technologies, including DriveCore and flexible DSP, to deliver powerful and high-quality audio performance. Their robust design, comprehensive connectivity options, and tailored control make them a premier choice for audio professionals seeking reliable and effective amplification solutions.
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