Crown Audio MT-601, 1201, 2401 operation manual Advanced Features Options

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Micro-Tech Series Power Amplifiers

5 Advanced Features

and Options

NOTE: For detailed information about these Crown amplifier features, please consult the Crown Amplifier Application Guide, available on the Crown website at www.crownaudio.com.

5.1 Protection Systems

Your Crown amplifier provides extensive pro- tection and diagnostic capabilities, including ODEP, ultrasonic/RF protection, drive protec- tion, and power supply fuses or breakers.

5.1.1 ODEP

Crown invented ODEP to prevent amplifier shutdown during demanding operation, and to increase the efficiency of the output circuitry.

To do this, Crown measured the safe operating area (SOA) of each output transistor before installing it in an amplifier. Next, Crown designed intelligent circuitry to simulate the instantaneous operating conditions of those output transistors. Its name describes what it does: Output Device Emulation Protection or ODEP. In addition to simulating output transis- tor operating conditions, it compares their operation to their known SOA. If ODEP sees that more power will be asked of the output devices than they can deliver, ODEP immedi- ately limits the drive level until it falls within the SOA. Limiting is proportional and kept to an absolute minimum — only what is required to prevent output transistor damage.

This level of protection enables Crown to increase output efficiency to never-before- achieved levels while greatly increasing reli- ability. The front-panel ODEP indicators show whether the amplifier is functioning correctly or whether ODEP is limiting the drive level.

5.1.2 Ultrasonic and Radio Fre- quency Protection

Micro-Tech amplifiers have a controlled slew rate. This means that their design puts a limit on the frequencies they can reproduce. The

controlled slew rate has no effect on audio per- formance because the high-frequency limit is well above 20 kHz. This approach protects the amplifier and tweeters from radio frequencies. An amplifier's slew rate only needs to be large enough to deliver the maximum voltage at the highest required frequency — higher slew rates actually let the amplifier reproduce unde- sirable frequencies.

5.1.3 Drive Protection

This system temporarily removes drive from the output stages to protect the amplifier and its loads, and prevents oscillation. Drive protec- tion can be activated in two situations. First, if dangerous subsonic frequencies or direct cur- rent (DC) is detected in the amplifier's output, drive protection will activate. The amplifier resumes normal operation when it no longer detects dangerous output. Activating this pro- tection is very unlikley, but improper source signals like subsonic square waves or a severely clipped signal can activate this sys- tem.

Second, the amplifier's fault protection system puts the affected channel into drive protection mode in rare situations where heavy common- mode current is detected in its output. The amplifier should never output heavy common- mode current unless its circuitry is damaged. Activating drive protection helps prevent further damage.

5.1.4Transformer Thermal Protection

This activates in the rare case where the unit's transformer temperature rises to unsafe levels. Then the amplifier will remove power from the affected channel's high-voltage power supply, which puts the channel in drive protection mode. The channel will return to normal opera- tion after its transformer cools to a safe temper- ature.

A transformer can overheat during very severe conditions: higher than rated output levels, excessively low-impedance loads, and unreas- ionably high input signals.

Micro-Tech amplifiers keep working under con- ditions where other amplifiers would fail. But even when a Micro-Tech's limits are exceeded, it will still protect itself — and your investment

— from damage.

5.1.5 Fuses and Circuit Breakers

120 VAC, 60 Hz models and all Micro-Tech 2400s have an internal fuse that protects the low-voltage power supply and cooling fan. The high-voltage power supplies for the Micro-Tech 600 and 1200 are protected by internal fuses, while the power supplies for the Micro-Tech 2400 high-voltage supplies are protected by circuit breakers.

With rated loads and output levels, the fuses (or circuit breakers) should shut down the amplfi- ier only in the rare instance of a catastrophic failure. ODEP protection keeps the amplifier operational under most other severe condi- tions. The fuses (or circuit breakers) can also shut down the amplifier if extremely low- impedance loads and high output levels result in current draw that exceeds their rating. Again, this should be possible only when operating outside rated conditions, as when the amplifier is used to drive a 1-ohm load in Stereo mode, or when an input signal is clipped severely.

Micro-Tech amplifiers do not blow their fuses or trip their breakers unless something is wrong. In the rare event that an internal fuse blows, please refer the unit to a qualified tech- nician. If a breaker in a Micro-Tech 2400 trips, try to identify and correct the problem before resetting the breakers. If the problem persists, refer the unit to a qualified technician.

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Operation Manual

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Contents 102990-8 Micro-Tech 600, 1200 601, 1201Some models may be exported under the name Amcron 06/04Use only with a cart, stand, bracket, or table Important Safety InstructionsOutput wiring Crown International, Inc Safety StandardDeclaration of Conformity European Representative’s Name and AddressTable of Contents Unpacking Your Amplifier Welcome How to Use This ManualFeatures You may also stack amps without using a cabi- net SetupInstall Your Amplifier Ensure Proper CoolingChoose Input Wire Connectors Shows connector pin assignments forChoose Output Wire and Con- nectors Output ConnectionsInputs Connect input wiring to Channel 1 only Wire Your System Stereo ModeBridge-Mono Mode Parallel-Mono ModeSet Input Sensitivity Set Ground Lift SwitchStartup Procedure Connect to AC MainsDo Not operate the amplifier with the Odep LEDs turning off PrecautionsOperation Power Switch Odep Indicators Output Device Emulation ProtectionEnable Indicator Dust FilterReset Switches Micro-Tech 2400 only Rear Panel Facilities Power CordStereo/Mono Modes Switch Input Sensitivity SwitchAdvanced Features Options Filter Cleaning Accessories Cooling Fan OptionsInput Connectors Option Circuit Theory Principles of OperationOverview Circuit Block Diagram Stereo OperationBridge-Mono Operation Parallel-Mono OperationEnergy reserve for the affected channel is dip- ping TroubleshootingHigh-voltage power supply fuse or breaker has blown Supply and fan are still working120 VAC, 60 Hz Units, Parallel mono mode Specifications120 VAC, 60 Hz Units, Bridge mono mode Weight 120VAC, 60-Hz units Net Weight Power Draw at IdleDimensions Width, Height, Depth Shippping WeightAC Power Draw Thermal Dissipation AC Power Draw Thermal Dissipation Micro-Tech Series Power Amplifiers Warranty 12/01Worldwide Except USA & Canada Purchase Order for Crown Dealer Crown Factory Service InformationVisa Card Number Exp. Date

MT-601, 1201, 2401 specifications

Crown Audio is synonymous with high-performance amplifiers, and their models 1201, 2401, and MT-601 embody the brand's commitment to quality and reliability in sound reinforcement. Each model caters to different needs, making them valuable assets in live sound and installation applications.

The Crown 1201 amplifier is designed for versatility, providing 120 watts per channel at 8 ohms. This model features Crown's patented "Power Factor Control," which ensures maximum power delivery with minimal distortion and heat generation. The 1201 is lightweight yet rugged, making it ideal for portable applications. It's equipped with comprehensive protection circuitry, including short circuit and thermal protection, safeguarding both the amplifier and connected speakers.

Moving to the Crown 2401, it ups the power with 240 watts per channel at 8 ohms. The 2401 also employs Crown's advanced input circuitry, which enhances audio clarity and reduces noise. Its design includes an intelligent cooling system with variable-speed fans, accommodating demanding situations while ensuring quiet operation. The amplifier's robust build quality and efficient power usage make it a favorite among sound engineers who require both reliability and performance.

The MT-601 is a versatile addition to Crown's lineup, known for its flexibility in various applications. Delivering 300 watts per channel at 8 ohms, the MT-601 features an advanced monitoring system that provides real-time feedback on system performance. This capability allows sound technicians to make adjustments on the fly, optimizing sound quality. The MT-601's lightweight chassis and modern design make it easy to integrate into any setup.

All three models embody Crown Audio's dedication to innovation through technologies such as output peak limiter and gain monitoring, which prevents signal clipping and distortion. They also feature variable-speed cooling fans that adapt based on the amplifier's thermal load, ensuring efficiency without compromising performance.

In summary, Crown Audio’s 1201, 2401, and MT-601 amplifiers showcase the brand’s expertise in delivering powerful, reliable audio solutions. With their unique features, robust build quality, and advanced technologies, these amplifiers meet the diverse needs of both live performance environments and fixed installations, making them an ideal choice for audio professionals.