6
The S1500 / S2000 Protection Circuitry
As noted in the “Guided Tour” section of this manual, the S1500 / S2000 front-
panel Protection LED indicates the activity of the relay speaker connection
circuitry. When the Protection LED is lit, this circuitry is active, and all connected
speakers are muted (provided with 0 volts DC), thus protecting them and
preventing any audible “thump” from occurring.
The following conditions will cause the Protection LED to go on:
• Initial power-up: For approximately five seconds after initial power-up, the
protection circuitry is activated and the speaker output is muted. If everything is
operating normally, you will hear an audible click at the conclusion of this brief
period, as the protection circuitry is deactivated and the S1500 / S2000 begins
delivering signal to connected speakers (at which point you’ll hear a click). It is
normal for the Protection LED to fade gradually after the amplifier is powered off.
• Overheating: A temperature sensing device in the S1500 / S2000 will cause
the protection circuitry to be activated (and the Protection LED to go on)
whenever the operating temperature of the unit rises above a safe level. To
guard against this problem, make sure the S1500 / S2000 receives adequate
ventilation on all sides and that both the front and rear panels are unobstructed.
• Severe overcurrent conditions: This occurs whenever the signal being input to
the S1500 / S2000 rises to a level above 20% THD (Total Harmonic Distortion).
• Shorted speaker cables: This will occur if, due to faulty wiring, the hot and
ground signals being output by the S1500 / S2000 short one another.
• Output impedance drops below 2 ohms: This can occur if the S1500 / S2000
is connected to inappropriate speaker systems (see the “Setting Up and Using
Your S1500 / S2000” section on page 5 in this manual for more information).
• DC voltage detected at speaker output: The most likely cause of this is an
internal failure.
In general, any time the Protection LED lights up (other than during the
approximately five seconds following initial power-up), there is reason to be
concerned. If this occurs, turn the S1500 / S2000 off immediately and carefully
check all wiring and external devices in order to locate and correct the condition
that caused the LED to light up in the first place.
For further assistance, contact your local Samson dealer. If purchased in the
United States, you can call Samson Technical Support (1-800-372-6766)
between 9 AM and 5 PM EST.
WARNING: If the Protection LED fails to go out (and you fail to hear the
accompanying audible click) approximately five seconds after power-up,
turn the S1500 / S2000 off immediately and check all external devices and
wiring for possible shorts or other defects.
PROTECTION
