Crest Audio 8002 Owner's Manual page 33

safety
6
DC Voltage
If an amplifier channel detects voltage at its output terminals, the out-
DC
put relay will immediately open to prevent loudspeaker damage.The Status
will turn red.
LEDs
Subsonic Frequencies
Built-in high pass filtering provides subsonic frequency protection for each
channel. In addition, a relay will open if excessive subsonic energy appears
at the output.
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