Speaker Protection

Thermal Protection

The internal fan(s) will keep the amplifier operating well within its intended temperature range under all normal conditions. If a chan- nel’s heat sink temperature reaches 75°C, (85°C for Models 7001 and 8001) which may indicate an obstructed air supply, clogged air filter, etc., that channel will independently protect itself by disconnecting its load and shutting down until it has cooled to 72°C ( 82°C for Models 7001 and 8001). During this time, the channel’s DC/Temp LED will light. If the power transformer gets too hot, its ther- mal sensing circuit will disconnect both channel outputs. Normal operation will resume automatically once the transformer cools to a safe level. During this time, the Active LED will extinguish, the Temp/DC and Clip/Limit LED’s will stay lit, and the cooling fan will stay running.

Short Circuit

If an output is shorted, the IGM and thermal circuits will automatically protect the amplifier. The IGM circuit senses the short circuit as an extremely stressful load condition and attenuates the signal, protecting the channel’s output transistors from overcurrent stress. If the short circuit remains, the channel will eventually thermally protect itself by disconnecting the load.

DC Voltage Protection

If an amplifier channel detects DC voltage at its output terminals, its output relay will immediately open to prevent loudspeaker dam- age. The channel’s Temp/DC LED will light.

Subsonic Frequencies

The Professional Series amplifiers have built-in 12 dB per octave high-pass filtering, cornered at 8 Hz, to provide subsonic frequency protection for each channel. In addition, a channel’s output relay will open if excessive subsonic energy appears at the output.

Turn-On/Turn-Off Protection

At power-up, the amplifier stays in the protect mode, with outputs disconnected, for about 3 seconds while the power supplies charge and stabilize. While the output relays are open, the Temp/DC LED’s light. When power is removed, the speaker loads immediately dis- connect so that no thumps or pops are heard.

AutoRamp Signal Control

Whenever a Professional Series amplifier powers up or comes out of a protect mode, the AutoRamp circuit activates. While the speak- ers are disconnected, the AutoRamp circuit fully attenuates the signal. After the output relay closes, the signal slowly and gradually raises up to its set level. The AutoRamp Signal Control circuit has some important advantages over the conventional instant-on circuits:

1.If a signal is present during power-up (or when coming out of protect), the speakers are spared a sudden, potentially damaging burst of audio power.

2.Because the gain is reduced until after the output relay closes, no arcing occurs at the contacts, thereby extending their useful life.

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Crest Audio Pro Series Power Amplifiers

Stereo Amplifier specifications

The Crest Audio Stereo Amplifier has established a notable reputation in the audio industry, particularly among professionals seeking dependable and high-performance amplification solutions. Renowned for its robustness and exceptional sound quality, this amplifier is a popular choice for both live sound applications and studio settings.

One of the standout features of the Crest Audio Stereo Amplifier is its outstanding power output, which ensures that it can drive a wide range of loudspeakers with ease. Typically available in various power ratings, these amplifiers can provide significant wattage, allowing them to handle high-demand audio situations without distortion. This makes the Crest Audio amplifier an excellent choice for large venues, theaters, and event spaces.

The design of the Crest Audio Stereo Amplifier prioritizes efficiency and performance. Utilizing high-quality components, the amplifier is constructed with a rugged chassis and offers extensive heat dissipation to ensure longevity and reliability during prolonged use. This durability is particularly crucial in professional settings where equipment is often subjected to rigorous conditions.

In terms of technology, Crest Audio amplifiers incorporate advanced circuitry that enhances audio fidelity and minimizes noise. The use of Class AB amplification technology allows for a balanced performance that delivers both output power and audio clarity. This technology enables the amplifier to produce rich, warm tones, making it particularly effective for musical genres requiring dynamic range and precision, such as classical and jazz.

Another notable characteristic of the Crest Audio Stereo Amplifier is its comprehensive protection features. These amplifiers are designed with built-in thermal, short circuit, and overload protection, ensuring that the equipment can withstand potential hazards without compromising performance. The intuitive LED indicators provide visual feedback on the status of the amplifier, allowing users to monitor operation easily.

Connectivity is another essential factor, with Crest Audio amplifiers typically featuring a variety of input and output options. This flexibility enables integration with different audio systems, whether for simple stereo setups or complex multi-channel configurations. The professional-grade speakON and binding post outputs ensure secure connections to loudspeakers, promoting optimal performance.

Overall, the Crest Audio Stereo Amplifier is a reliable, high-performance solution for any audio professional. With its powerful output, sturdy construction, advanced technology, and user-friendly features, this amplifier continues to be a top choice for delivering exceptional sound quality in various applications. Whether in a studio environment or a live concert setting, the Crest Audio Stereo Amplifier stands out as a trusted tool for achieving audio excellence.