8The F1200 / F800 Protection CircuitryThe F1200 / F800 Protection LED relay speaker connection circuitry is activewhen the amp[[lifier is powered on or off. When the circuitry is active, and allconnected speakers are muted (provided with 0 volts DC), thus protecting themand preventing any audible “thump” from occurring.The following conditions will cause the Protection circuitry to activate:• Initial power-up: For approximately five seconds after initial power-up, the pro-tection circuitry is activated and the speaker output is muted. If everything isoperating normally, you will hear an audible click at the conclusion of this briefperiod, as the protection circuitry is deactivated and the F1200 / F800 beginsdelivering signal to connected speakers (at which point you’ll hear a click).• Overheating: A temperature sensing device in the F1200 / F800 will cause theprotection circuitry to be activated (and the Protection LED to go on) wheneverthe operating temperature of the unit rises above a safe level. To guard againstthis problem, make sure the F1200 / F800 receives adequate ventilation on allsides and that both the front and rear panels are unobstructed.• Severe overcurrent conditions: This occurs whenever the signal being input tothe F1200 / F800 rises to a level above 20% THD (Total Harmonic Distortion).• Shorted speaker cables: This will occur if, due to faulty wiring, the hot andground signals being output by the F1200 / F800 short one another.• Output impedance drops below 2 ohms: This can occur if the F1200 / F800 isconnected to inappropriate speaker systems (see the “Setting Up and UsingYour F1200 / F800” section on page 7 in this manual for more information).• DC voltage detected at speaker output: The most likely cause of this is an inter-nal failure.For further assistance, contact your local Samson dealer. If purchased in theUnited States, you can call Samson Technical Support (1-800-372-6766)between 9 AM and 5 PM EST.