MM8077

150W 7-CHANNEL CURRENT FEEDBACK POWER AMPLIFIER CIRCUIT FOR SUPERIOR SOUND

The MM8077 is expertly crafted to meet all your high powered needs and drive even the most demanding speakers by designing the entire unit to deliver consistent and precise power wherever and however you need it.

Key Features

Clean And Consistent Power

The power supply features a high current toroidal power transformer along with high power (71WVDC) filter capacitors with a total 100,000µF capacitance to easily handle sharp short-term transient peaks.

Ultimate Powerhouse

Designed for the ultimate music and movie surround sound experience, the Marantz MM8077 7-channel power amplifier delivers power and detail, and is rated at 150 watts per channel into 8 ohms, and 180 watts per channel into 6 ohms.

Power The Most Demanding Of Systems

Designed for the ultimate music and movie surround sound experience, the Marantz MM8077 7-channel power amplifier delivers power and detail, and is rated at 150 watts per channel into 8 ohms, and 180 watts per channel into 6 ohms.

Toroidal Transformer Power Supply

The power supply features a high current toroidal power transformer along with high power (71WVDC) filter capacitors with a total 100,000µF capacitance to easily handle sharp short-term transient peaks.

Featuring Our Unique Current Feedback

Featuring our unique current feedback discrete power amp output stages that are identical for all channels, the MM8077 is 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.

Masterfully Built

The output devices are mounted on our unique dual extruded aluminum alloy heat sink assembly, configured in a tunnel arrangement that provides both passive and active cooling. The massive heat sinks feature multiple ribbed fins that provide a large passive cooling area, and the assembly is book-ended with a whisper quiet fan that automatically kicks in to provide near silent active cooling when the soundtrack heats up. As the fan is mounted internally directly to the heat sinks, and not externally to the chassis cover as is often the case, even when it’s running, it’s designed to be whisper quiet.

Marantz MM8077 Specs
Channels    7
Power Output    8 ohms Rated: 150 W per channel (20 Hz to 20 kHz, THD = 0.08%, 2-channels driven) 
6 ohms Rated: 180 W per channel (20 Hz to 20 kHz, THD = 0.08%, 2-channels driven) 
6 ohms Maximum: 210 W per channel (1 kHz, THD = 10%, 2-channels driven)
Output Connectors    6 to 8 ohms
Frequency Response    8 Hz to 100 kHz (1 W, 8 ohms) (± 3 dB)
Damping Factor    100
Input Sensitivity/Impedance    1.2 V / 22 k ohms (unbalanced) 
2.4 V / 30 k ohms (balanced)
Signal-to-Noise Ratio    105 dB (IHF-A)
Voltage Amplification Level    29 dB
Input & Output    7 x Balanced inputs 
7 x Unbalanced inputs 
7 x Speaker channels 
1 x IR flasher input 
1 x DC control input 
1 x DC control output 
1 x Remote control input 
1 x Remote control output
Switch    Balanced and unbalanced
Supply Voltage    240 VAC, 50/60 Hz
Power Consumption    Operational: 800 W
Standby: 0.4 W
Dimensions (WxHxD)    17.3 x 7.3 x 15.1" / 440.0 x 185.0 x 383.5 mm
Weight    39.7 lb / 18.0 kg

Marantz MM8077 Multi-channel Amplifier

By Brian Kahn | March 26, 2014

The MM8077 is Marantz's biggest multi-channel amplifier, with 150 watts of power in each of its seven channels. The MM8077 ($2,399) is designed to complement the new Marantz AV processors, such as the AV8801 that we recently reviewed. The design of the MM8077 follows that of the AV8801, with a porthole in the center of the brushed-black front panel and curved sides that make for a clean and attractive style.

While not especially heavy at 39 pounds, the MM8077 feels solid due to its construction, which includes a copper-plated chassis with multi-layer top and bottom panels. A single, large toroidal-transformer-based power supply feeds all seven channels. The MM8077 utilizes a current feedback design, with complementary push-pull circuits, and a Wilson current mirror, which is said to reduce distortion in the high sound range. This amplifier borrows other design traits from Marantz's classic amplifiers, including high-efficiency power transistors that are said to improve transient performance and proprietary "condensers" (capacitors) with 100,000 micro-farads of storage capacity. In short, the circuit design borrows characteristics from Marantz's well-regarded stereo amplifiers in an attempt to bring the musicality that Marantz is known for to this modern seven-channel amplifier, which is capable of 150 watts into each channel into eight ohms (180 watts into six ohms).

Additional Resources

• Learn more about Marantz at HomeTheaterReview.com
• Check out our review of the Emotiva UPA-700 amplifier at HomeTheaterReview.com
• Check out more reviews in our amplifier page at HomeTheaterReview.com

All of this power can generate lots of heat, which can damage components unless it is drawn away. The MM8077 uses a combination of passive and active cooling techniques. A large cooling tunnel made out of heatsinks draws heat away like a chimney; when this approach cannot draw away enough heat, temperature sensors engage variable-speed cooling fans to increase cooling. The internal heatsink design keeps the exterior clean and simple. The back panel has balanced and single-ended inputs for each channel, an IEC power plug port, and five small jacks for control functions, including a 12-volt trigger in/out, flasher input, and remote control in/out. If your system cannot work with any of these control options and you do not want to have to walk over to the amplifier to turn it on and off, you are still in luck, as the MM8077 has a signal-sensing feature that can be configured to power up the amplifier when it senses an audio signal. 

When I had the MM8077 in my reference theater system, I watched an old favorite, Heat (DVD, Warner Home Video). The Marantz did a good job of keeping the dialogue clear and easy to understand, while providing plenty of detail and power for the more dynamic scenes, such as the bank robbery shootout. When I listened to Adele's "Set Fire to the Rain" from the album 21 (XL Recordings, Columbia), her voice was reproduced with a balance of precision and natural ease that made for a realistic presentation.

Paula Cole's "Tiger" from the album This Fire (CD, Warner Brothers) is a dynamic track with strong, deep bass. I compared this track through three amplifiers: the Marantz and two more expensive models from Halcro and Krell. The Krell and Halcro amplifiers produced more detailed and solid soundstages and had more impact and control in the bass region, but the Marantz came much closer to the performance levels of the more expensive amplifiers than the large price differential would suggest.

High Points

• The seven channels of power provide flexibility to cover either a 7.1-channel system or both a 5.1- and two-channel system via a single amplifier.
• The performance level of the MM8077 is a clear step above receiver-based amplifiers, with not only increased dynamics but a natural, musical presentation.
• Marantz offers a five-channel version, the MM7055, which can be seamlessly used to power any additional channels in a multi-channel system, as both amplifiers have the same gain and sonic characteristics.
   

Low Points

• The amplifier had plenty of power for most situations, but it seemed to have difficulty driving the woofers of the B&W 800 Diamonds with the same speed and precision as my Krell and Halcro amplifiers. I was able to get around this by setting the bass management to divert the lowest frequencies to the subwoofer, but it is still something to consider.
• I would like to have the option to bridge channels for more power to my front channels, rather than having some channels sit unused. However, as this amp has a single power supply for all channels, I am not really sure how much of a difference this would make, other than for bi-amping the speakers.
• The speaker terminals were not up to the build quality of the rest of the amplifier. They were of the five-way binding post variety and were okay, but did not seem as solid as the rest of the amplifier. Audiophile cables with spade connectors will not fit, and neither would my double banana connectors. Small spade connectors, bare wire, or single banana connectors are needed.
   

Competition and Comparison
The HomeTheaterReview.com multi-channel amplification page keeps up to date with the multi-channel amplifiers on the market. Some other options include Emotiva's UPA-700 ($499) with 80 watts per channel; this amplifier may be a good choice for more efficient speakers. For systems needing even more channels of amplification, the Onkyo PA-MC5500 1699 offers nine channels. The Wyred 4 Sound MMC Series of amplifiers comes in three-, five-, and seven-channel options ($1,999 for the five-channel version), utilize the ICE amplifier modules and provide a slightly cooler sonic profile.

Conclusion
I used the MM8077 in a couple of systems, with speakers from Wisdom, MartinLogan, and my reference B&W 800 Diamonds. Overall, the Marantz MM8077 performed extremely well, with a sonic character that leaned toward a warmer, fuller sound. I was able to listen to stereo and multi-channel music for hours without any fatigue. The "warm" sonic character adds liquidity and body to the critical midrange and is thankfully balanced to also provide the detail necessary for demanding multi-channel soundtracks. My only caveat is that some difficult-to-drive, full-range speakers may push this amplifier to its limits. I have no problems recommending the MM807 to listeners who are searching for a multi-channel amplifier that is equally at home with both music and movies.

Check out the gallery below for the more pics of the MM8077 . . .