Protection features | Crest Audio CC 4000, CC 5500, CC 2800, CC 1800

5protection features

CCTM owner’s manual

CCSeries amplifiers incorporate several circuits to protect both themselves and loudspeakers under virtually any situation. Crest Audio has attempted to make the amplifiers as foolproof as possible by making them immune to short and open circuits, mismatched loads, DC voltage, and overheating. If a channel goes into the Automatic Clip Limiting or ACL™ gain reduction mode, the speaker load remains connected, but clipping percentage or output power are instantly reduced. When a problem occurs that causes a channel to go into a protection mode, the Temp LED for that channel will glow. DC voltage on the output, excessive subsonic frequencies, or thermal overload will cause the channel’s output relay to disconnect the speaker load until the problem is corrected or the amplifier cools down.

automatic clip limiting (ACL)

Any time a channel is driven into hard, continuous clipping, the clip limiter circuit will automatically reduce the channel gain to a level just slightly into clipping, guarding the speakers against the damaging high power continuous square waves that may be produced. Situations that may activate the clip limiter include uncontrolled feedback, oscillation, or an improper equipment setting or malfunction upstream from the amplifier.Normal program transients will not trigger the clip limiter; only steady, excessive clipping will.The ACL LED will glow brightly and continuously when limiting occurs.

IGM™ impedance sensing

CCSeries amplifiers feature innovative circuitry that allows safe operation into any load. When an amplifier sees a load that overstresses the output stage, the Instantaneous Gain Modulation (IGM) circuit adjusts the channel gain to a safe level.This method of output stage protection is far superior to conventional, brute force type limiting found on other amplifiers. The IGM circuit is sonically transparent in normal use and unobtrusive when activated.

thermal protection

The internal fans will keep the amplifier operating well within its intended temperature range under all normal conditions. If a channel’s heat sink temperature reaches 75°C, which may indicate an obstructed air supply, that channel will protect itself independently by disconnect- ing its load and shutting down until it has cooled. During this time, the channel’s Temp LED will glow, the Active LED will go out, the ACL LEDs will stay lit and the cooling fans will run at high speed. The CC 1800 utilizes one common heat sink and single fan, but retains the separate circuitry.

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 over current 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 or subsonic frequencies at its output terminals, its output relay will immediately open to prevent loudspeaker damage.

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CC 1800, CC 4000, CC 2800, CC 5500 specifications

Crest Audio is renowned for its high-performance amplifiers, and the CC series stands out as a testament to the brand's commitment to quality and innovation in professional audio. The CC 1800, CC 5500, CC 2800, and CC 4000 models each bring unique features and technologies designed for various applications in live sound and installations.

The Crest Audio CC 1800 is a powerful workhorse, delivering 900 watts per channel at 4 ohms. It features a robust power supply and high-quality output devices, ensuring excellent performance and reliability. The CC 1800 is equipped with comprehensive protection circuitry to safeguard against overheating and short circuits, enhancing its durability in demanding environments. Its lightweight design combined with a compact chassis allows for easy transport and setup, making it a favorite among sound professionals.

Next in the lineup, the CC 5500 steps up with an impressive output of 1,300 watts per channel at 4 ohms. This amplifier is engineered for high efficiency and low distortion, making it ideal for driving large speaker systems in concert applications. The CC 5500 incorporates a sophisticated thermal management system, allowing it to operate at maximum capacity without compromising audio fidelity. Additionally, its versatile input options make it compatible with various sound systems, enhancing its utility across different setups.

The CC 2800 is designed for versatility, offering a balanced output of 1,000 watts per channel at 4 ohms. It features advanced circuitry that maximizes headroom and minimizes noise, ensuring clear, powerful sound reproduction in any setting. The CC 2800 also includes an integrated limiter system to prevent signal clipping, preserving audio integrity during high-energy performances. With its rugged build and quality components, this model is perfect for touring professionals and fixed installations alike.

Finalizing the series, the CC 4000 is a powerhouse, producing an extraordinary 1,500 watts per channel at 4 ohms. Its advanced design incorporates an innovative feedback topology that allows for exceptional transient response and low distortion levels. The CC 4000’s durable construction ensures reliability over time, even during extensive use. It also offers multiple outputs and detailed monitoring capabilities, making it a top choice for larger venues and more extensive audio setups.

In summary, the Crest Audio CC series — CC 1800, CC 5500, CC 2800, and CC 4000 — represents a range of amplifiers with advanced technologies, robust construction, and high performance. Each model is tailored to meet the specific needs of audio professionals looking for reliability and superior sound quality in various applications.

Crest Audio CC 4000, CC 5500, CC 2800, CC 1800 owner manual Protection features

Models: CC 1800 CC 4000 CC 2800 CC 5500