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Proficient Audio M8 (Factory Refurbished)

8-channel multi-room power amplifier

1 Review

Item # 879M835X8R

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Our take on the Proficient Audio M8 (Factory Refurbished)

Factory-refurbished and repacked with care

If you've been looking for a high-quality multichannel amplifier, but have been working on a tight budget, this factory-refurbished model may be just what you need. Proficient Audio is so confident you'll like it just as much as a brand new unit, they're including their full two-year warranty.

Flexible power where you need it

Proficient Audio's M8 eight-channel amplifier combines classic styling, a versatile design, plus high-performance sound for your whole-house music system. You can easily configure this powerful amp to best suit your specific multi-room applications. Enjoy clear stereo sound in four rooms, or combine two channels into one to give your speakers more juice — a great option for power-hungry outdoor speakers. Use a single channel of power for mono sound in smaller listening areas, like a walk-in closet or bathroom.

Enjoy music throughout your home

The M8 can distribute music from one audio source, such as a networked music streamer, to multiple rooms in your home. Or you can connect additional sources directly to the individual amplifier channels and assign each one to a single listening room. Each channel features its own separate level control so you can easily adjust the volume to fine-tune the sound of your system. Optional audio and voltage sensing capabilities automatically turn the amp on and off with the rest of your
system. And to top it off, the M8's heavy cast-aluminum front panel makes it a handsome addition to any equipment rack.

Product Highlights:

  • 8-channel amplifier
  • power output:
    • 35 watts RMS per channel into 8 ohms (two channels driven, remaining channels driven at 1/8 of rated power)
    • 55 watts RMS per channel into 4 ohms (two channels driven, remainder undriven)
    • each pair of adjacent channels are bridgeable for 110 watts RMS into 8 Ohms (two channels driven, remainder undriven)
  • frequency response (at 1 watt, 8 ohms): 9.5-80,000 Hz (±1.5 dB)
  • signal-to-noise ratio: greater than 120 dB
  • total harmonic distortion (at rated power): 0.070%
  • individual RCA audio inputs for all 8 channels
  • stereo RCA main bus and auxiliary inputs for connecting audio sources
  • stereo RCA main bus and auxiliary outputs for "daisy-chaining" up to four amplifiers for very large systems
  • source selection switch for each channel allows you to select between the common bus or auxiliary inputs, or the individual channel input
  • individual selector switches allow three audio playback options for each channel: left, right, or left plus right (mono)
  • independent line-level controls for all 8 channels
  • three turn-on modes: audio signal sensing, voltage trigger, and manual
  • 12-volt DC control output
  • gold-plated binding post speaker connectors for all channels
  • eight front-panel LED status lights with independent thermal and short-circuit protection circuits for each channel
  • detachable AC power cord
  • 17-3/16"W x 5-7/8"H x 20-1/8"D
  • weight: 30 lbs.
  • warranty: 2 years
  • Our 60-day money-back guarantee

What's in the Box:

  • Refurbished 8-channel amplifier
  • 6' AC power cord
  • 2 Rack-mount brackets
  • Installation/User Guide

Proficient Audio M8 (Factory Refurbished) Reviews

Average Customer Review(s):

(1 Review)

Proficient Audio M8 (Factory Refurbished)

Anonymous from Arkansas on 9/25/2014

Crutchfield Customer Review (What's this?)

Not happy with the quality or ease to use. Thought I would be able to pick the speakers I wanted to use but only on the back of the unit is that available




Hands-on research

Product Research


Distributed Audio: The Proficient M8 amplifier delivers the power and fidelity needed to distribute music throughout your home. This amplifier includes the necessary features needed for flexible, reliable custom installation. Sophisticated design and superior internal components, result in outstanding sound quality, performance, and long term reliability.

35W x 8Ch High-Current Amp: The Proficient M8 amplifier is rated at 35 watts x 8 channels (in 8 at 20-20kHz with 2-channels driven and 0.07% THD), or 55 watts x 8 channels (in 4 at 20-20kHz with 2-channels driven and 0.1% THD). It provides pure, high-current sound.

Bridgeable: The power output of adjacent amplifier channels can be combined to provide extra power when needed in certain locations & applications. This is easily accomplished by flipping a single switch on the amplifier's rear-panel. Bridged power rating of the amplifier is 110 watts x 4 channels (in 8 at 20-20kHz with 2-channels driven and 0.5% THD)

Binding Posts: The Proficient M8 amplifier is fitted with gold-plated, binding posts for each channel. The sixteen binding-post terminals will accept bare-wire (up to 12AWG), pin-connectors, and banana plugs (dual or single). Us the following chart to determine the proper wire gauge based on actual overall wire length from the M8 the speaker.

Speaker Wire LengthSpeaker Wire Gauge
150'16 AWG
400'14 AWG
1000'12 AWG

Flexible Input Selection: With selectable Line, Bus, and Aux inputs, the M8 can simultaneously output multiple audio sources. Each of the amplifier channels can be assigned a variety of source inputs; a dedicated input can be assigned to each channel or each channel can be configured to play common signals from the Bus or Auxiliary inputs. This provides the flexibility needed in sophisticated custom audio installation.

  • Line Inputs: The Line inputs (RCA) allow amplification of up to eight mono or four stereo sources for discrete playback in multizone applications.
  • Bus Input: The Bus input (stereo RCA) can each feed the same audio source to any of the eight channels allowing optional distribution of mono and/or stereo sources to multiple rooms.
  • Aux Input: The Aux left and right RCA inputs are fed to the respective left and right output channels for distribution of two mono sources to up to four rooms each or one stereo source to four rooms.

Controls: The Proficient M8 amplifier offers Channel Input selection and Channel Level adjustment on the rear-panel.

  • Channel Input Switch: Each Eight 4-position switches allow you to select the input to each channel. These switches allow multiple audio sources to be connected and played simultaneously. The Line In setting feeds audio only to its dedicated channel. The Bus L/R setting sets a channel's input to the source connected to the amplifier's Bus input. The Aux L/R setting will set a channel's input to the source connected to the Aux input.
  • Channel Level Adjustment: Each channel has its own level adjustment. This allows the loudness of each speaker to be perfectly matched to its location and application and balance your system's sound.

Bus Loop: For larger systems, the Bus Loop can be used to connect up to four additional M8 amplifiers for a total of up to twenty rooms of amplified audio.

Protection Circuitry: Each channel of the amplifier is individually protected. If the advanced circuitry determines that a channel must be shut down for protection (a rare occurrence) only the channel affected will be turned off, while the other channels continue to play. Once conditions return to normal, the affected channel will be turned back on and operate as normal.

Note: When the Protection LEDs (Red) on front of the amplifier are lit, it is indicating either a fault in the wiring, the speaker, or the amplifiers of that particular channel.

Power Modes: There are three ways to turn the amplifier on; Constant, Trigger, or Audio Sense. This allows the amplifier to operate seamlessly as part of a sophisticated custom installation. The 3-way power mode switch is located on the amplifier's rear-panel.

  • Constant: Select Constant mode when you wish to manually turn the amplifier on and off by using the front mounted power button.
  • Trigger: Use Trigger mode if you prefer the amplifier turn on when it receives voltage (3-30V) from an external source and turn off once that voltage has stopped. The voltage source must be connected to the trigger input jack (3.5mm) on back of the amplifier.
  • Audio Sense: Audio Sense mode turns on the amplifier when the amp's main input receives an audio signal. Once the signal stops, the amplifier waits 3 minutes and then turns itself off.

Trigger Output: A separate output trigger (3.5mm) allows the amplifier to activate other components via a 12-volt trigger.

Cast Aluminum Front-Panel: The Proficient M8 amplifier features a cast aluminum front-panel for added rigidity and a great look.

Air Flow Design: The Proficient M8 is designed to run cool under most normal operating conditions, but may run warm with multiple channels running at moderate to high output. It is typical for an eight-channel amplifier to generate certain amount of heat dissipation that need to be properly ventilated. When installing the M8 a few steps should be taken to assure proper air flow:

  • Never block the vent holes on the top or bottom of the M8.
  • Never remove the feet on the bottom of the M8.
  • Leave at least 2" above and 1" on each side of the M8 for free air flow.
  • Whenever possible, provide vent holes in the shelf under the M8 to increase air flow into the bottom of the unit.
  • Leave the back of the cabinet as open as possible for good air circulation.
  • Place other system component on separate shelves.
  • Install fans in cabinets and racks when equipment is generating high heat levels.
Note: Closed spaces such as equipment cabinets and racks can get hot with the heat generated by microprocessors and motors in various devices. Providing proper ventilation for good air flow will help keep the temperature down and protect not only the M8, but all system components and help preserve their longevity.
Rack Mountable: The amplifier includes a set of rack ears for rack mounting applications.

Our Product Research Team

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