General Information

To enhance the ease of installation and obtain optimum performance from the PA640, we recommend that you first become familiar with all its features and special capabilities by studying the descriptions and

POWER	REMOTE
	ON/OFF

PA640

SIX CHANNEL POWER AMPLIFIER

SYLMAR, CA

MADE IN U.S.A.

LEVEL		BRIDGED	LEVEL		BRIDGED	LEVEL		BRIDGED
1V	C H 1	C H 2	1V	C H 3	C H 4	1V	C H 5	C H 6

	STEREO		STEREO		STEREO
3V	.2V	3V	.2V	3V	.2V

LINE INPUTS				LINE INPUTS				LINE INPUTS
LINE INPUTS				LINE INPUTS				LINE INPUTS

INPUT PANEL

Fig. 1 The Model PA640

instructions in this manual.

The PA640 was designed to meet the audio power amplifier needs of custom installed multi-zoned systems with high sonic quality. It's 6-5-4-3 multichannel capability permits a wide variety of other uses as well, such as surround sound home theater applications. Specific features and technology are as follows:

•Cost/Size Efficiency. The PA640 features six 40-watt power amplifiers. This permits each PA640 to drive 3-zones in a multi-zone system -- each with a 40-watt stereo amplifier per zone. The low profile design, plus multiple amplifiers in a single package, delivers high quality at a reasonable price.

•Input Level Flexibility. The input levels are individually adjustable (per stereo pair) from a low of 0.2 volts up to 3.3 volts. This gives the installer the ability to adjust the overall gain of the system or zone. For instance, there may be a need to adjust the amplifier to deliver a controlled, maximum sound level into a zone when the volume control on the preamp is set to maximum. This would act as a volume limiter for any particular zone (i.e. to prevent the kids from over-driving wall speakers, etc.).

•6-5-4-3 Output Flexibility. Each pair of amplifiers can be bridged to allow several channel and power output capabilities. It can be configured into four power packages as follows:

-Six 40-watt amplifiers.

-One 140 and four 40-watt amplifiers.

-Two 140 and two 40-watt amplifiers.

-Three 140-watt amplifiers.

This gives the PA640 added use in many other applications, such as driving surround sound speaker systems.

•Low Impedance Capability. Each amplifier is 2-Ohm safe under music conditions in stereo mode and 4-Ohm safe when bridged. This means, for instance, that you can drive two pairs of 8-Ohm speakers in stereo mode in each zone with ease.

•Discrete Output Devices. All output and driver transistors are separate devices connected in a full- complimentary Darlington configuration. This provides highest reliability in concert with highly linear dynamic performance free of T.I.M. and slew induced distortions.

•Auto Protection Circuit. Protects the PA640 if a short or very low impedance is detected at the speaker terminals. Each amplifier pair is protected separately, with an LED indicator showing which pair is in protection. Normal operation is restored automatically within 3 to 4 seconds after the short is removed.

•Remote ON/OFF Jack. This jack allows the PA640 to be powered on and off by a positive DC voltage ranging between 4 and 30 volts (11 mA @ 12 V). Specifically, it permits the 12 volt CO (Control Output) from the Xantech ZPR68 to power one or more PA640's on and off automatically with zone ON/OFF commands.

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PA640