Crown Audio CH Series Advanced Features and Options, CH and CL Series Power Amplifiers, page

CH and CL Series Power Amplifiers

4 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.

4.1 Protection Systems

CH and CL Series amplifiers are protected against shorted, open or mismatched loads; overloaded power supplies; excessive temperature, chain destruction phenomena, input overload damage and high-frequency blowups. They also protect loud- speakers from input/output DC, large or dangerous DC offsets and turn-on/turn-off transients.

4.1.1 Power Circuit Breaker

A back-panel push button is used to reset the circuit breaker that protects the power supply. Available in CH1, CH2, CL1 and CL2.

4.1.2 Proportional-speed or 3-speed Fan

In the CH1, CH2, CL1 and CL2, a proportional- speed fan directs the airflow through the amplifier for cooling. In the CH4 and CL4, a 3-speed Fan-On- Demand does the same thing.

4.2 Advanced Features

4.2.1 BCA® (CH4 and CL4 Only)

BCA (Balanced Current Amplifier) is Crown’s pat- ented, cutting-edge technology that gets more power out of an amplifier with less waste than was ever before possible. A completely new adaptation of standard amplifier design, Crown’s BCA “switch- ing” amplifier design provides for high output, exceptional reliability and nearly twice the efficiency of typical amplifier designs.

While switching designs have been used success- fully in other applications, these designs were never before suitable for use in precision, high-power audio amplifier applications. Crown’s BCA technol- ogy changes that, with a totally new paradigm for amplifier design that represents the future of profes- sional amplifiers.

With their superior efficiency, BCA amplifiers can help to keep power requirements lower, while still providing excellent audio reproduction. And Crown BCA amplifiers are tough—easily handling very low (and highly reactive) load impedances, even under extreme conditions. In fact, Crown BCA amps have far out-performed competitive amplifiers in tests where the amplifier was run as much as 12 dB into clip for extended periods of time.

4.2.2Switching Power Supply with PFC (CH4 and CL4 Only)

Crown’s new Switching Power Supply with PFC provides a range of benefits over both non-switch- ing and conventional switching power-supply designs.

Typical non-switching power supplies require large transformers in order to produce the required power at the output stage. These transformers must be large to absorb the waste that occurs when operat- ing at 50 to 60 Hz (standard AC supplied by the power company).

By contrast, switching power supplies can operate with a much smaller (and lighter) transformer because they first convert the AC up to a much higher frequency, thereby reducing waste.

4.3 Options

4.3.1 Input Sensitivity

Input Sensitivity is factory set to1.4V for each chan- nel. With this setting, a 1.4V input signal will drive the amplifier to full power into an 8-ohm load when the Level Controls are turned to maximum. This set- ting works best when the amplifier is being driven by equipment with a +4 dBu output. Optionally, the Input Sensitivity for each channel can be individu- ally set to either 0.775V or 26 dB. To have the input sensitivity changed on your amplifier, contact an authorized Crown Service Center

4.3.2 Crown SST Modules

Crown optional SST (System Solution Topologies) modules were specially designed to improve the fidelity and versatility of your audio system. They feature a variety of professional signal routing and filtering capabilities, with active crossovers that allow the audio signal to be split and sent to auxil- iary amplifiers. Your amplifier may have come with an SST module already factory-installed, or your choice of SST modules can be easily added to the amplifier by any authorized Crown Service Center.

For information on wiring and configuration of amplifiers equipped with an optional Crown SST crossover module, please refer to the SST Cross- over Reference Manual included in your literature package.

Refer to the following descriptions for an overview of available Crown SST crossover modules. Crown plans to release additional accessory plug-in mod- ules offering a range of advanced features and capa- bilities. Watch for new releases.

Operation Manual page 19