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. 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. 2-Ohm Loads: Except for an occasional flash, keep the “CLIP ” indicator dark to avoid overheating the amplifier channel. Clipping should be kept to a reasonable minimum. An amplifier’s peak current draw at full output power into 2 ohms is several times what the “normal ” draw is, but its various protection circuits will prevent this condition lasting more than a minute or two. Short Circuit Protection - The Vplus series amplifiers all come with built-in Output Short Circuit Protects. The Output Short Circuit Protection protects the output devices of the amplifier from short circuits and stressful loads. If your speaker lines short, the amplifier automatically detects this problem and discontinues operation for that channel. If one side of your amplifier becomes shorted and American Audio® - - Vplus Series Amplifiers Power Amplifier User Manual Page 13 goes into protect mode, the other side will continue to operate normally. During short circuit protection, the "Clip" LED and “Protect" LED will light simultaneously indicating amplifier fault. All channel output during the “Short Circuit Protection" will be interrupted (i.e. no sound output). Short Circuit Protection can usually be traced back to the signal output line (i.e. speaker line). Check the line from the output terminal of the amplifier to the speaker. If this line good, check the internal speaker connections and components. A short circuit will usually be traced to a bad cable or a bad speaker component and is rarely traced to the amplifier itself. Thermal Protection - A single variable-speed fan on the V1000plus and dual variable speed fans on the V2000plus and V3000plus amplifiers provide adequate cooling. During low level output the fans run at normal speeds. During high output and as heat raises, (exceeding 90°C.), the fans will run at higher speeds to aid the cooling process. If the heatsink temperature exceeds 91°C., the amplifier will mute until the amplifier cools down. When the amplifier cools below 90°C., the amplifier will return to normal operations. Be sure not to operate your amplifier below the minimum load ratings to reduce the risk of overheating problems. Input/Output Protection - The input circuits are isolated by 10k resistors. An ultrasonic network uncouples RF from the output and helps keep the amplifier stable with reactive loads. Operating Voltage (AC Mains) - The serial number label indicates the correct AC main voltage. 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. Gain Controls - The gain controls are located on the front panel and are calibrated in 2dB of attenuation from full gain. It is best to adjust the amplifier so no “hissing” is heard from speakers with no music being played, this will ensure the lowest possible distortion during normal operation. Low Cut Filter (V2000 and V3000 Only) - The low-cut filter removes extremely low frequencies from the audio signal that could cause speaker distortion or damage. The dip switches on the rear panel allows you to enable or disable the filter for each channel, as well as adjust either a 50Hz or 30 Hz cut-off. Always use the 50 Hz filter setting if you are using the amplifier to drive a distributed line system (also known as a constant-voltage line, 70 volt line, etc.). The dip switches on the rear panel allows you to configure the low cut filter. The diagram below detail the functions of each dip switch, the functions are also printed on the rear panel of the amplifier. Configuring the Low Cut Filter: Activating Low Cut Filters - Dip switches 1 and 4 activate and deactivate the Low Cut Filter. Channel 1 filters is control by dip switch 1 and channel 2 filter is controlled by dip switch 4. Low Cut Frequency Selector - When the Low Cut Filter is activated, dip switches 2 (channel 1) and 3 (channel 2) will control the frequency roll-off. When dip switches 2 and 3 are in the "ON" the filter will cut off frequencies at and below 30Hz, when...