Rolls RA900 Description, Rear Panel LOW-CUT Switches Inputs ST/BRDGE Switch Fuse, Operation

DESCRIPTION

FRONT PANEL

POWER
CHANNEL A	PROTECT	CHANNEL B
	CLIP
	SIGNAL
	POWER	RA900

0 10 0 10

POWER: Applies power to the RA900 when connected to a properly grounded and powered ac outlet.

CHANNEL 1 / 2 LEVEL CONTROLS: Adjust the output level of the indicated channel. When in Bridged mode, Channel 1 control adjusts the output level. POWER LED: Indicates the RA900 is connected to an ac outlet and the power is on.

SIGNAL LED: indicates that signal is present in the indicated channel.

CLIPLED: Indicates overload in the indicated channel

PROTECT LED: Indicates that the indicated RA900 channel has gone into PROTECT Mode - the output will shut off.

REAR PANEL
LOW-CUT SWITCHES		INPUTS	ST/BRDGE SWITCH FUSE
		INPUT	CAUTION
			MINIMUM LOAD IMPEDANCE
POWER AMPLIFIER	B	BALA
			4 OHM BRIDGE
			2 OHMS PER CHANNEL

	+			B	A
	-					LOW	AMP MODE
+	1		LOW	1 2 3 4
			CUT FILTER 1			4 CUT FILTER			FUSE
2	INPUT		ON=30Hz 2			3 ON=30Hz	STEREO	BRIDGE
-			OFF=50Hz			OFF=50Hz			15A/120V
3	THRU	A	- BRIDGE MONO +
	B
			Channel B			Channel A
							GROUND
							LIFT

THRU OUTPUTS GND LFT PWR

LOW-CUT SWITCHES: Connects or disconnects the low-cut filters.

INPUTS: XLR and 1/4” TRS input jacks.

ST/BRDGE SWITCH: Selects either Stereo or Bridged mode.

FUSE: Contains the 12A 250V fuse

THRU: Male XLR jacks - hard-wired to the input jacks.

OUTPUTS: 5-Way binding post output terminals

GND LFT: Connects or disconnects the ouput ground to chassis ground.

PWR: Connects to the power cable.

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OPERATION

STEREO

	IN		IN
		INPUT		CAUTION
				MINIMUM LOAD IMPEDANCE
POWER AMPLIFIER	B	BAL	A
				4 OHM BRIDGE
				2 OHMS PER CHANNEL

	+			B	A
	-					LOW	AMP MODE
+	1		LOW	1 2 3 4
			CUT FILTER 1			4 CUT FILTER			FUSE
2	INPUT		ON=30Hz 2			3 ON=30Hz	STEREO	BRIDGE
									15A/120V
-			OFF=50Hz			OFF=50Hz
3	THRU	A	- BRIDGE MONO +
	B
			Channel B			Channel A
							GROUND
							LIFT

BRIDGED

			IN
		INPUT		CAUTION
				MINIMUM LOAD IMPEDANCE
POWER AMPLIFIER	B	BAL	A
				4 OHM BRIDGE
				2 OHMS PER CHANNEL

	+			B	A
	-					LOW	AMP MODE
+	1		LOW	1 2 3 4
			CUT FILTER 1			4 CUT FILTER			FUSE
2	INPUT		ON=30Hz 2			3 ON=30Hz	STEREO	BRIDGE
									15A/120V
-			OFF=50Hz			OFF=50Hz
3	THRU	A	- BRIDGE MONO +
	B
			Channel B			Channel A
							GROUND
							LIFT

CONNECTION

Connect the amplifier in either Stereo or Bridged Mono mode as shown above. Turn the unit off before making any connection changes.

INPUTS

The RA900 inputs are XLR balanced, or 1/4” unbalanced.

OUTPUTS

The output terminals take a standard banana type plug, or they may be un- screwed so the end of the wire may be stripped and inserted into the hole on the top of the terminal - then tightened.

GROUND LIFT

The Ground Lift switch has been provided to disconnect the circuit ground from chassis ground. This may help eliminate unwanted ground hum or buzz.

OPERATING VOLTAGE

The serial number of your RA900 will indicate the correct AC operating voltage. Connecting the unit to the wrong voltage may damage the amplifier.

LOW CUT FILTER

The Low Cut Filter removes ultra-low frequency content from the audio signal that could possibly damage or cause distortion in a loudspeaker system. The DIP switch on the rear panel enables or disables the filter independently for each

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