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Power a Small-Sized Whole-Home Audio System with 35 Watts of Power to Each of 4 Speakers
4-Channel, 2-Zone Power Amplifier
4-Channel, 2-Zone Power Amplifier
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Rear Panel Connections
4-Channel, 2-Zone Power Amplifier
Item# 81278
Free shipping on orders over $175 - See Details


  • 4 internal individual amplifiers can power up to 2 audio zones
  • Internal amplifiers can be driven individually or bridged to suit almost any application
  • Use a single source for all zones or a different audio source on each zone
  • LED status indicators on the front panel of the amplifier

Essential Info

The most essential component of any whole-home audio system is the amplifier. This four channel amplifier will provide enough power for small to medium sized applications with control of up to two different zones (pairs of speakers). Each channel (speaker) is powered by a 35 Watt amplified output, enough to deliver for a full spectrum sound experience. However, this versatile device also allows for the internal amplifiers to be bridged, creating greater audio output for a one-channel application. A single source (TV, iPod, MP3 player, CD player, turntable) can be connected to the "Common Bus" so that each zone has the same audio output. Alternatively, the amplifier is flexible enough to let each zone be fed audio individually via a "Local Input" from differing zones or sources; this means you can have audio from your TV on in the home theater zone and music from your iPod or MP3 player on in a different zone such as your backyard. Volume control can be set manually on the amplifier for the entire system or for each zone individually. Another option is to install a volume control between the amplifier and your speakers. This product also features LED status indicators let you know which zone or zones are active at all times; you can conserve energy by turning off zones that don't need to be active. The 4-Channel, 2-Zone Power Amplifier is a shelf-top audio component that provides a great foundation for audio distribution and control in any home.

Please Note: Speakers and volume controls sold separately.

Variations of this amplifier sold separately are:
  • 12-Channel, 6-Zone Power Amplifier with IR Control
  • 12-Channel, 6-Zone Power Amplifier without IR Control
  • 6-Channel, 3-Zone Amplifier with IR Control

  • Manuals/Software

    What's Included

  • 4-Channel, 2-Zone Power Amplifier
  • Owner's Manual
  • More Info

    Cost/Size Efficiency
    The PA435X features four 35-watt power amplifiers. This permits each PA435X to drive 2-zones in a multi-zone system -- each with a 35-watt stereo amplifier per zone.

    4-3-2 Output Flexibility
    Either pair of amplifiers can be bridged to allow several channel and power output capabilities. It can be configured into three power packages as follows:
  • Four 35-watt amplifiers. (4 Mono speaker outputs or 2 Stereo Zone outputs)
  • One 70 and two 35-watt amplifiers. (1 Mono 70 Watt and 1 Stereo 35-watt output)
  • Two 70-watt amplifiers. (single Zone Stereo 70-watt output)

    Status LED Indicators
    These indicators, one for each channel pair, provide the following status information:
  • GREEN LED: Indicates Amplifier is ON
  • RED LED: Indicates associated channel output is in a CLIPPING state. LED will go back to GREEN 5-6 seconds after clipping subsides.
  • ALL LED’s OFF: Indicates both amplifier channels are OFF or in STANBY MODE

    MODE Switch
    Switches the amplifier pair between STEREO, MONO and BRIDGED modes.
  • In STEREO mode, the two amplifiers operate independently of each other for 35 Watts of output each.
  • In MONO mode, left and right input signals are summed internally for Mono output from each of the two amplifiers. When interfacing a mono audio source, either the Left or Right inputs may be used.
  • In BRIDGED mode, the two amplifiers are bridged for a single channel of high power output (70 Watts @ 8 Ohms). Either the Left or Right input may be used to drive the resultant single channel amplifier.

    Line Inputs and Input Level Control
    These RCA-type jacks are the audio inputs for each of the amplifier pairs. Connect them to the Preamp Output jacks of a driving preamp output with good quality RCA-type patch cables. Note that the inputs are marked LEFT-A-RIGHT, LEFT-B-RIGHT signifying the stereo channel pairs. Both the LEFT and RIGHT jacks are always active even when the MODE switch is set to the MONO or BRIDGED mode. The Input LEVEL Control has a screwdriver adjustable control (for each stereo or bridged pair) which allows the input level for full rated power output to be adjusted over a range of 0.2 volts to 3 volts (24.3 dB). Normally you would adjust the driving preamp to maximum volume, then set this control to the maximum volume that the client desires for a given zone or room. This prevents the system from being driven to unwanted power levels.

    Volume Setting Capabilities
    Once installed, you have the option of using the volume control of the amplifier as the sole volume control for a zone or the whole system. The volume control can also be used to adjust the amplifier volume to a desired fixed level and use the volume action of a connected preamp instead. Additionally, a maximum volume setting can be established, which allows the amplifier to be set to deliver a controlled maximum sound level into a zone when the volume is ramped to maximum. This acts as a volume limiter for the system (e.g. to prevent the kids from over-driving wall speakers, etc.).

    Low Impedance Capability
    Each amplifier is 4-Ohm safe under music conditions in stereo mode and 8-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.

    Peak/Clip LED Indication
    Whenever either amplifier channel output starts to enter a clipping state, a front panel LED will illuminate RED. After the amp stops clipping the LED will return to its normal state 5-6 seconds after clipping stops.

    Auto Protection Circuit
    This feature protects the PA435X if a short or very low impedance is detected at the speaker terminals with each amplifier pair protected separately. Normal operation is restored automatically within 3 to 4 seconds after the short is removed.

  • Specifications


    Manufacturer Product No.:PA435X
    Number of Channels:4
    Power Output:
  • 35 Watts at 8 Ohms (rated continuous power, each channel, all 12 channels simultaneously driven, 20 Hz to 20kHz, at rated THD)
  • 55 Watts at 8 Ohms or 80 Watts at 4 Ohms
  • Bridged Power Output:150 Watts at 8 (Short term continuous, one pair driven at 1 kHz, at rated THD)
    Rated THD<0.08%
    Dampening Factor:>100 at 50 Hz,1/2 rated power
    S/N Ratio:>100 dB
    Frequency Response:12 Hz to 55 kHz at 1 Watt +/- 3 dB
    Input Sensitivity:0.5 V maximum, 1.0 V default, Off minimum; at rated power, stereo mode
    Input Impedance:
  • LOCAL Inputs: 22 kOhms
  • COMMON AUDIO BUS Inputs: 70 kOhms
  • Power Source:120 VAC, 60 Hz (240 V Version: 240 VAC, 50 Hz)
    Power Consumption:
  • No Signal: 14 Watts (0.25/0.13 A)
  • 4 channel at 1/10 rated power: 105 Watts (3.0/1.5 A)
  • 4 channel at rated power: 420 Watts
  • 4 channel Bridged 465 Watts
  • Remote On/Off/Mute CI1 & CI2 Voltage/Current:+5 V to +30 VDC (16 mA at +12 VDC)
    Line Fuse Rating:6.25 A Slow Blow
    Dimensions:17" W x 4" H x 11.5" D (432mm W x 102mm H x 293mm)
    Weight:20.4 lbs (9.3kg)

    Important notes:
    Only merchandise credit for defective items returned within 30 days of purchase. No other returns allowed on this item.
    Manufacturer contact information: Xantech LLC, Tel: (800) 843-5465 Ext 355


    Rear Panel Connections       
    Rear Panel Connections       



    Speakers  Speaker Wire  Volume Controls   
    Speakers  Speaker Wire  Volume Controls   

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