Crown Audio STUDIO AMPLIFIER Parallel-Monomode, results in distortion and inefficient operation

Studio Reference I & II Professional Studio Amplifiers

greatly degraded. Also, turn down the channel 2 level	is very different from the other modes and requires
control (fully counterclockwise).	special attention.
Note: The channel 2 input and level control are not de-	To select Parallel-Mono mode, turn off the amplifier and
feated in Bridge-Mono mode. Any signal feeding chan-	slide the stereo/mono switch to the left (as you face the
nel 2 will work against the channel 1 signal, and usually	back panel). Connect the input signal to channel 1 only.
results in distortion and inefficient operation.	The channel 2 input and level control are bypassed in
Connect the load across the two red (+) binding posts	this mode, so they should not be used.
(see Figure 3.6). The positive (+) loudspeaker lead	Note: It is normal for the channel 2 IOC indicator to stay
connects to the red channel 1 binding post, and the	on in Parallel-Mono mode.
negative (–) or ground lead from the loudspeaker con-	Connect the load to the channel 1 output as shown in
nects to the red channel 2 binding post. Do not con-
nect the black binding posts (–). Also, the load must be	Figure 3.7. The positive (+) lead from the loudspeaker
balanced (neither side shorted to ground).	connects to the red channel 1 binding post, and the
CAUTION: Only connect balanced equipment	negative (–) or ground lead from the loudspeaker con-
	nects to the black channel 1 binding post. Finally, in-
(meters, switches, etc.) to the Bridge-Mono output.	stall a jumper wire of at least 14 gauge between the
Both sides of the line must be isolated from the in-	channel 1 and channel 2 red binding posts.
put grounds or oscillations may occur.	CAUTION: When Parallel-Mono wiring is installed,
3.3.3 Parallel-Mono Operation
	do not attempt to operate in Stereo or Bridge-Mono
Parallel-Mono mode is used to drive loads with a total	mode until the wiring is removed (especially the
impedance of less than 4 ohms (see Bridge-Mono if the	jumper wire). Failure to do so will result in high dis-
load is 4 ohms or more). Wiring for Parallel-Mono mode	tortion and excessive heating.

MIXER

STUDIO REFERENCE AMPLIFIER

PARALLEL-MONO MODE

CHANNEL 1
	ADD A 14 GAUGE
	OR LARGER
	JUMPER BETWEEN
THE CHANNEL 2	THE CHANNEL 1
INPUTS ARE	AND 2 RED (+)
NOT USED	BINDING POSTS
	CH-2	CH-1

FX

PUSH PUSH

ReferenceS T U D I O

STEREO

PARALLEL BRIDGE

MONOMONO

CAUTION: TURN OFF AMPLIFIER

BEFORE CHANGING THIS SWITCH!

Fig. 3.7 Parallel-Mono Wiring

–

+

LOUDSPEAKER

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