Protect Indicators, Introduction, Inspection

channel, as well as sets it for either a 50Hz or 30Hz rolloff. Always use the 50Hz setting if you are using this amplifier to drive a distributed line system (also known as a 70 Volt line).]

PROTECT INDICATORS

The RA900 has two protection modes; 1. Overload and 2. Thermal.

In the event of signal overload the CLIP and PROTECT LEDs will light and the output of the amplifier will be limited. If the output is short circuited, the output level LEDs go out, the PROTECT led will light, and the output of the amplifier will be muted. Check the speaker wiring for shorts.

The unit’s circuitry is protected from overheating by a variable-speed fan. How- ever, if the heatsink temperature rises above 90 degrees C, the output will mute until the amplifier cools down.

The RA900 input circuitry is isolated by 10K ohm resistors. An ultrasonic network decouples RF from the output and helps keep the amplifier stable with reactive loads.

INTRODUCTION

Thank you for your purchase of the ROLLS RA900 Professional Power Amplifier. The RA900 Power Amplifier is a two channel amp with two 410 watt RMS - 4 ohm outputs via 5-way binding posts. It may be bridged and connected to a 4 or 8 ohm load supplying up to 1100 Watts or 850 Watts respectively. The unit is housed in a painted steel chassis and includes a special high performance transformer, and a fused power line.

The RA900 is ideal for DJs, musicians, or other sound reinforcement applications such as powering front-of-house speakers or monitors.

INSPECTION

1. Unpack and inspect the RA900 box and package.

If obvious physical damage is noticed, contact the carrier immediately to make a damage claim. We suggest saving the shipping carton and packing materials for safely transporting the unit in the future.

2. Please complete the Warranty Registration Card and return it to the factory.

Table of Contents
INTRODUCTION	1	INSPECTION	1
INSTALLATION	1	FRONT PANEL	2
REAR PANEL	2	OPERATION	3
STEREO	3	BRIDGED	3
CONNECTION	3	INPUTS	3
OUTPUTS	3	GROUND LIFT	3
OPERATING VOLTAGE	3	LOW-CUT FILTER	3/4
PROTECT INDICATORS	4
SPECIFICATIONS	5
WARRANTY	Back Cover

INSTALLATION

Connect the power cord to an AC power source, connect the input to the signal source and to the RA900 via the XLR or 1/4” input jacks. Turn the Volume controls fully counterclockwise (off), and turn on the power switch, the power LED should light. With the program material running, slowly increase the Volume controls until the desired level of sound is present. There is a two-second turn-on delay pro- vided to prevent possible speaker damage in case all equipment is on a signal power strip.