Protection Features
The Peavey CS Series incorporates several circuits to protect the amplifier and speakers under virtually any situation. Peavey has made 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 DDT™ gain reduction mode, the DDT LED illuminates. The clipping percentage or output power is instantly reduced. When a problem occurs that causes a channel to go into a protection mode, the PWR (Power) LED for that channel will turn off. DC voltage on the output or excessive subsonic frequencies will cause the triac crowbar circuit to activate to protect the speakers. If the amplifier overheats, the signal will be removed from the channel that is at fault until the amplifier cools down, thus protecting the amplifier.
Distortion Detection Technique (DDT) Limiting
Any time a channel is driven into hard, continuous clipping, the DDT circuit will automatically reduce the channel gain to a level just slightly into clipping, guarding the speakers against the damaging,
LFC Impedance Sensing
CS Series amplifiers feature innovative circuitry for safe operation into any load. When an amplifier senses a load that overstresses the output stage, the Load Fault Correction circuit adjusts the channel gain to a safe level. Extreme load fault under high power levels will cause the signal to be muted for the associated channel. This method of output- stage protection is far more effective than the standard limiting found on conventional power amplifiers. The LFC 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 85° C (which may indicate an obstructed air supply), that channel will independently protect itself by muting its input signal and shut down until it has cooled. During this time, the PWR LED will go out and the cooling fans will continue operating at high speed.
Short Circuit
If an output is shorted, the LFC and thermal circuits will automatically protect the amplifier. The LFC circuit senses the short circuit as an extremely stressful load condition and attenuates the signal, protecting the channel’s output transistors from
DC Voltage Protection
If an amplifier channel detects DC voltage or subsonic frequencies at its output terminals, the output triac crowbar circuitry will activate immediately to prevent speaker damage.
Turn-On/Turn-Off Protection
Upon powering up, the amplifier stays in Protect mode, muting the input signal for approximately four seconds while the power supplies charge and stabilize. Also, when power is removed, the input signals are muted so that no thumps or pops are heard.
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