Lexicon LX-7 - Manual (Page 17)

2-9
Basic Operation
LX Power Amplifiers
DC PROTECTION
Each channel includes DC protection to prevent DC and
frequencies below 10Hz from reaching the speakers. If this
protection activates, the output relay will click off and the
corresponding front panel channel status LED will no longer be lit.
After approximately 4-seconds, DC protection will be
automatically deactivated. The relay will click on and the
corresponding channel status LED will light blue. If DC or
frequencies below 10Hz are still present, DC protection will be
automatically reactivated. The amplifier will continue to engage
this protection until the problem is no longer present.