Protection Features
The CS 800H incorporates several circuits to protect both itself and loudspeakers under virtually any situation. Peavey has attempted to make the amplifier as foolproof as possible by making it immune to short and open circuits, mismatched loads, DC voltage, and overheating. If a channel goes into the Distortion Detection or DDT 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 or DC 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.
DDT
Peavey’s DDT compression system allows maximum performance of the amplifier/speaker combination by preventing the power amp from running out of headrooom (clipping). This compression system is activated by a unique circuit that senses signal conditions that might overload the amplifier and reduce the amplifier’s gain when clipping is imminent. The threshold of compression is clipping itself and no specific threshold control is used. This technique effectively utilizes every watt available for the power amplifier to reproduce the signal while at the same time minimizes clipping and distortion, and thus significantly reduces the potential of loudspeaker degradation and damage.
LFC Impedance Sensing
The CS 800H features innovative circuitry that allows safe operation into any load. When an amplifier sees a load that overstresses the output stage, the Load Fault Correction 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 LFC circuit is sonically transparent in normal use and unobtrusive when activated.
Thermal Protection
The internal fan will keep the amplifier operating well within its intended temperature range under all normal conditions. If a channel’s heat sink temperature reaches sufficient temperature which may indicate an obstructed air supply, that channel will independently protect itself by disconnecting its load and shutting down until it has cooled. During this time, the channel’s TEMP LED will light. During this time, the ACTIVE LED will go out, the Temp and DDT LEDs will stay lit and the cooling fan will stay running at high speed.
Short Circuit
If an output is shorted, the LFC circuit will automatically protect the amplifier. The LFC circuit senses the short circuit as an exteremly stressful load condition and mutes the signal, protecting the channel’s output transistors from over current stress. Approximately 1.5 seconds later, the RampUp circuit will attempt to return the amplifier to normal operation. If the short is still present, the LFC circuit will again mute the signal. This cycle of operation will continue until the short is removed from the output.
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. The channel’s DC LED will light.
Turn-On/Turn-Off Protection
At
10
