©American Audio® - www.americanaudio.us - ELX Series Power Amplifier User Manual Page 11
PROTECTION:
Thermal Protection - If the amplifiers operating temperature runs over 105°C (221°F) the amplifier will go into thermal protection to
prevent damage from over heating. The Protect Indicator LED located on the front of the amp will light up, and the output signal will
be muted. The fans will start to run at max speed to allow the amp to return to a safe operating temperature. To prevent amplifier over
heating, make sure your input signal is not clipping (Red LED indicator located at the front), and that you are not overdriving the amp.
Make sure not block the airflow input and output vents and always use the amp in an enviroment that is no higher than 30°C (86°F).
Never use a speaker load that exceeds power or impedance ratings.
Clip Limiter - When the input signal overloads, the “CLIP LED’s” will indicate a signal overload, at this time, the master volume should
be lowered to reduce distortion. If the input gain level is not reduced the built-in limiter will activate. During signal overload, the lim-
iter will reduce the input audio signal enough to minimize the amount of clipping. A limiter takes the gain of an overloading signal and
reduces it, the reduction in gain reduces distortion that can cause damage to your speakers and amplifier. During normal operation
below clipping, and momentary clips on peaks, the limiter does not affect the audio signal and is inaudible. It will allow brief clipping of
peaks and will only activate when continuous, hard clipping occurs. During excessive clipping the limiter will reduce the audio signal
enough to minimize the amount of clipping. When the input signal decreases enough that clipping ends, the limiter will deactivate and
cease its gain reduction. The limiter has a fixed threshold and can not be adjusted. NOTE: If input signal is clipping or exceeds linear-
ity working range of input circuit, then the Clip Limiter will not work.
Short Circuit Protection -
The ELX Series amplifiers all come with built-in Short Circuit Protection. If a short circuit is detected on
the output signal, the Clip and Protect Indicator LEDs will both glow. This protection makes the output transistors work at a safe
range and there will be no output from the amp. The amp will recover after 10 seconds after the terms of the short circuit have been
removed.
AC Local Power Protection -
If the AC power voltage is lower than 70% of the required voltage, the power supply will turn off auto-
matically until the power voltage is normal. NOTE: The correct AC main voltage is listed above the Power Cord input. Connecting to
the wrong voltage is dangerous and may damage the amplifier. Always be sure the source voltage for your areas matches the required
voltage for your amplifier.
DC Protection -
If the output signal has a larger DC voltage (=2.6V), in order to protect the speaker, the DC protection circuit will start-
up. When the DC protection circuit starts up, the Protection Indicator LED (1) will glow and the amp will go mute.
Safe Power Levels at Different Output Loads:
8-Ohm Loads: The amplifier can operate at practically any power level without risk of overheating. However, if it is pushed hard
enough to continually light the “CLIP” indicator, the amplifier’s average output power can reach 150 watts.
4-Ohm Loads: If the “CLIP” indicator flashes occasionally, the amplifier is approaching its maximum long-term power capacity. If it is
lit about half the time, the amplifier channel will probably go into thermal protection within a few minutes.
