Samson 170 owner manual Appendix E Bridged Mono Mode Servo-550 Only, Input LEFT+ Output RIGHT+

Appendix E: Bridged Mono Mode (Servo-550 Only)

STEREO

BRIDGED

MONO

INPUT

LEFT(+)

OUTPUT

RIGHT(+)

OUTPUT

The Servo-550 amplifier provides a rear-panel switch that allows it to be used in a bridged mono mode. When this switch is placed in the “Stereo” (up) position, the Servo-550 functions as a true stereo amplifier, where both of the two independent amplifier channels (left and right) can receive different input signal and produce independent output signal. However, when the switch is placed in the “Bridged Mono” (down) position, both amplifier channels process only the signal present at the left input, thus producing a monophonic output signal with a true 550 watt output (into 8 ohms).

WARNING: Bridged mono mode is to be used only when the Servo-550 is connected to an 8 ohm speaker load. Use of bridged mono mode with speaker loads of 4 ohms or less can result in severe damage to the unit due to excessive heat and current limiting and will void your warranty!

The illustration on the left shows how this works. In bridged mono mode, the polarity (phase) of the right output signal is reversed relative to that of the left output signal. Both channels then process the same signal, with the speaker load connected so that power is derived from both channels. The effective voltage swing seen by the load is thus doubled so that the power output is doubled.

When using the Servo-550 in bridged mono mode, be sure to connect the loudspeaker as shown in the illustration below, with the hot (+) terminal of the left channel connected to the positive input of the speaker and the hot (+) terminal of the right channel connected to the negative input of the speaker. Do not use the ground output terminal of either channel (the speaker load must “float” away from the amplifier chassis).

10A/250V				SERVO 550 STUDIO AMPLIFIER
FUSE
		CAUTION; REPLACE
		WITH THE SAME TYPE
		FUSE AS INDICATED.
E	F	UTILISER UN FUSIBLE		S/N
	SU	DE RECHANGE	DE
		MEME TYPE.
USE CLASS 2 WIRING MAXIMUM LOAD IMPEDANCE 4Ω
BRIDGED MONO 8Ω		-		+
	GROUND	+RIGHT	LEFT + GROUND
		OUTPUT 275W/4Ω

CAUTION	!	CAUTION
RISK OF ELECTRIC SHOCK		HEATSINK MAY BE HOT!
		DO NOT BLOCK AIRFLOW
DO NOT OPEN		OR OVER-HEATING MAY
		OCCUR

TO PREVENT SHOCK DO NOT OPEN. NO USER

SERVICABLE PARTS INSIDE. REFER SERVICING

TO QUALIFIED SERVICE PERSONNEL.TO

PREVENT FIRE OR SHOCK HAZARD DO NOT

EXPOSE TO RAIN OR MOISTURE.

RIGHT LEFT ~AC INPUT

115V/60Hz,1080W

SAMSON

STEREO

BRIDGED

MONO

LEFT

RIGHT

INPUTS

(BALANCED 10KΩ /0dBu)

TIP RING SLEEVE

TIP +

RING -

SLEEVE GND

+

-

Never use bridged mono mode during stereo operation. If loudspeakers are connected to both channel outputs of the Servo-550 when used in bridged mono mode, they will be severely out of phase with one another (there will be an extreme loss of low end).

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