About The Marantz MM7055 5 Channel Power Amplifier

A superb 5 Channel Power Amplifier from Marantz that will add more presence to both movies and music and at a very reasonable price.

The overall quality of your entertainment system's sound is extremely dependent on the power amplifier section and that is whether it is a small integrated amplifier or a large power amplifier like the MM7055. It is not simply a matter of the more Watts the better because your speakers are like a heavy train going up a hill - it doesn't just need more power, but more clean and controlled power. Likewise, the power amplifier section needs to deliver sufficient quantities of clean, instantly available power on demand. So there must be enough clean power that is available in an instant when you turn up the volume of when a dynamic passage demands it and especially so with today's movie soundtracks. So how does the Marantz MM7055 measure up?

5-Channel Power Amplifier

The Marantz MM7055 five-channel power amplifier delivers power and detail, and is rated at 140 Watts (into 8 Ohms, at 20Hz-20kHz with 0.08%, driving 2 channels)  and 170 Watts (into 6 Ohms, at 20Hz-20kHz with 0.08%, driving 2 channels). The MM7055 power amp matches perfectly with the Marantz AV-8802 or AV-7703 home theatre preamp/processors (sold separately). The power supply features a high current toroidal power transformer along with high power (71WVDC) filter capacitors with a total 33,000µF capacitance to easily handle sharp short-term transient peaks. Featuring Marantz' unique current feedback discrete power amp output stages that are identical for all channels. In fact, the MM7055 is equipped with the same complimentary push-pull circuit as the far more expensive Marantz SM-11S1 power amp, providing minimal phase shift and excellent detail resolution. It is also equipped with multiple high current discrete power transistors that feature high slew rate and wide operating bandwidth to extract the most detail from today's high resolution audio formats. The current/voltage conversion section has a Wilson current mirror circuit to improve circuit stability and high-speed processing.

The chimney-shaped heat sink efficiently processes the heat emitted from the amp and a quiet cooling fan removes the heat from the chassis. A high-sensitivity temperature sensor IC is used to control the cooling fan's rotation speed to match the amount of heat generated by the amp. The copper-plated chassis provides isolation from extraneous noise, and features a multi-layer reinforced bottom panel assembly for maximum rigidity along with triple-layer top cover. Elegantly finished in anodized black satin, the MM7055 features the classic Marantz ringed porthole display with a blue illumination accent that includes a display on/off function.

Other Features

With the Auto Standby Mode turned on, this component will enter standby mode after approximately 30 minutes (continuous) with no input signal. A blue indicator on the front panel display and a blue ring around the display light when the power is on; the blue ring around the display can be turned off if you prefer. Separate red indicators on the display light when the protection circuit or Auto Standby feature is engaged.

Speaker Outputs: The five speaker output terminals are binding posts will accept single banana plugs and bare wire. A plastic collar prevents the use of spade terminations.

Inputs: Each channel has an RCA (unbalanced) and XLR (balanced) input. Separate switches for each channel specifies which is engaged.

Remote Power Control: This unit is equipped with a remote power control function; when a compatible Marantz preamp is connected, this unit's power can be switched on and off simultaneously with the preamp. The RCA Remote Control input is connected to the preamp and the Remote Control output can be connected to other compatible Marantz components; CD player, DVD player, Tuner, etc.

In The News

"This amp incorporates the same current feedback discrete circuitry that Marantz uses in its superb-sounding SM-11S1 stereo power amplifier that I reviewed for Stereophile in 2008. It produces plenty of power at another price that's difficult to believe...Its musical heart was in the right place and at a price that can't be beat...The MM7055 offers excellent value for the money...Together, (with the AV7703) they get you near the top of the performance heap for a low price that was unimaginable just a few years ago." - Home Theater Magazine.

Our Take On Marantz MM7055 Power Amplifier

Even with the advent of 7.2 and 9.2 channel surround sound systems, most of our customers still opt for tried-and-true 5.1 channel sound. Recognising this fact, Marantz designed and built this 5 channel power amplifier as the primary companion to their AV7005 preamp/processor, but it also partners well with any Home Theatre Receiver with appropriate outputs. If you want to step up to 7.2 or even 9.2 surround sound, then you can easily add one or more MM7025 140 Watt stereo (2 channel) power amplifiers to your system for more surround channels or multi-room audio. The MM7055 is comfortable driving high-performance speakers. If your preamp or A/V processor has XLR outputs, you can connect to this amp's XLR inputs and enjoy the superior sound quality they provide.

Main Features & Specifications

• Design: 5-channel power amplifier
• Discrete Current Feedback circuit for accurate, natural sound at all volume levels
• Power: 140 Watts per channel into 8 ohms (20-20kHz) at 0.08% THD, with 2 channels driven
  • 170 Watts per channel into 6 ohms
• Frequency Response: 8-100kHz (±3 dB)
• Signal-to-Noise ratio: 105 dB
• Input Sensitivity:
  • RCA: 1.2 V/22 kΩ
  • XLR: 2.4 V/30 kΩ
• One RCA and One XLR input for each channel
• DC trigger input/output: Yes
• IR flasher input: Yes
• Power Supply: Massive toroidal power transformer for high current and low noise
• Speaker Terminals: Gold-plated binding post speaker terminals
• Power Consumption: 660 Watts
  • Standby Power: 0.2 Watts
• Detachable Power Cord: Yes
• Finish: Black
• Dimensions (WxHxD): 440 x 384 x 185mm
• Nett Weight: 15.2kg
• Manufacturer's Warranty: 3 Years

Note: Features & Specifications Subject To Change Without Notice. E&OE