The new, nine-channel, PA-MC5500 takes its place as Onkyo's top of the line amplifier. Being a nine-channel amplifier the PA-MC5500 is a good match with the new group of nine-channel processors (including the recently reviewed Onkyo PR-SC5508). Even if your home theater system is a more traditional five of seven channel setup, the nine channels of amplification provide a variety of setup options. The extra channels can be used for bi-amplification or to drive two stereo zones in addition to a 5.1 system.
Additional Resources
• Read more multi-channel amplifier reviews by the staff at HomeTheaterReview.com.
• Search for speakers in our Floorstanding Speaker Review section.
• Look at dozens of AV receiver options.
The THX Ultra2 certification insures that no matter the configuration that the amplifier is used in, there is sufficient power to handle the job. The amplifier is rated at 150 Watts per channel into eight Ohms with two channels driven. While this may seem like a modest amount, the amplifier never seemed to be straining at reasonable listening levels in my five-channel system.
The PA-MC5500 features Onkyo's WRAT (Wide Range Amplifier Technology) topology, push-pull amplification design with three-stage inverted Darlington circuitry, auto-power down function to reduce energy waste, a twelve volt trigger as well as balanced and single-ended inputs. Behind the sculpted aluminum front panel of this 51-pound amplifier is a large toroidal transformer then a large heatsink that runs the width of the amplifier. The backside of the heatsink has a pair of 22,000 µF capacitors, which are flanked by nine-circuit boards, which contain the above-described Darlington circuits and "audio-tuned reference capacitors" and "custom-designed large power transistors to drive high currents". The circuit boards feature µm thick copper traces to handle the high current demands without impedance problems.
I connected the amplifier to my system using balanced interconnects even though the Onkyo is not a true balanced design. I used a variety of speakers including some from MartinLogan, Dynaudio and Acoustic Zen. The MartinLogan and Acoustic Zen speakers proved to be the most challenging for the Onkyo amplifier. Driving the six-Ohm Acoustic Zen Adagio's (Adagio front left and right, Adagio Juniors at center and rear) at the louder end of reasonable for a few hours resulted in a very warm amplifier. Comparing the Onkyo to other multi-channel amplifiers I have had in my system I found that the revealing tweeter of the Adagio's showed that the Onkyo was not quite as open and airy as the Marantz MM-8003 amplifier but the Onkyo had more impact on the low end. The MartinLogan Summits revealed that the several times as expensive Halcro MC-50 were more revealing and less likely to get congested in the midrange area.
Overall the Onkyo was well balanced with the high end being only slightly forward. This was most noticeable at high volumes through the Adagio speakers where the treble tilted towards hardness. Any other sonic shortcomings were those of omission. Quite simply, the Onkyo performed very well as far as it went but it did not reach absolute reference levels is dynamics, resolution and transparency, nor did I expect it to. The amplifier performed as well as, if not better than one could expect a $1,699 amplifier to do.
Read about the high points and the low points of the Onkyo PA-MC500 on Page 2.
High Points
• The PA-MC5500's nine channels of flexibility provide many connection options and eliminate the need for a second amplifier in most nine-channel or multi-zone systems.
• The PA-MC5500's soundstaging, imaging and dynamics on movies and multi-channel music was very satisfying.
• The amplifier comes packaged with a trigger cable and labels to
identify the speaker cables, something that will become important when
connecting nine separate sets of loudspeakers.
Low Points
• The PA-MC5500's soundstage on stereo tracks was lacking depth and the
overall level of refinement would keep me from using it in an absolute
reference level system. Those looking to upgrade their receivers or
enter into a mid-fi setup would be well suited with the PA-MC5500 in
their system.
• Operationally, I found the loud clicks when the amplifier was turning
on and the bright blue glow of the LED lamp on the faceplate
distracting-I wish Onkyo would have provided a switch to dim or disable
the lamp.
Competition and Comparisons
There aren't a lot of nine channel amplifiers out there (I can't think
of any) let alone ones retailing for well under $2,000. However there
are seven and five channel amplifiers available and while they lack two
or four channels of amplification compared to the PA-MC5500, they make
up for it in total power and price. For instance, Outlaw Audio's 7500 Multi-Channel Amplifier
may only offer five channels of amplification but all five channels
produce 200 Watts of power into eight Ohms and a staggering 300 Watts
into four, making it more suited to drive my less than efficient
MartinLogans more effectively. The 7500 is a little cheaper at $1,599
as well.
The reigning king of value for dollar amplification these days is
Emotiva and their seven channel amp, the UPA-7, packs 125 Watts across
all seven of its channels but for the best bang for your buck their XPA-5 is the amp of choice.
With 200 Watts per channel into eight Ohms (300 Watts into four) across
all five of its channels the XPA-5 is a staggering achievement and a
tremendous value at $899. If you needed nine channels of amplification
you could easily buy two XPA-5s and be in the same financial range as
the PA-MC5500-but with more power. Down side to this setup is the fact
that the XPA-5 is far larger than the PA-MC5500, meaning two would be
otherworldly.
Conclusion
Onkyo's PA-MC5500 is a solid value at $1,699. I would have no problems
recommending this amplifier for use in a multi-channel system. Many of
the newer multi-channel amplifiers feature digital amplification
circuits. While some of them are well implemented, I find analog
circuits to sound more natural and to be a better fit with music
reproduction.
The PA-MC5500 is well suited for the role it is designed to play,
the power for a multi-channel theater system. It does a good job
reproducing soundtracks with intelligibility of dialog, sufficient
dynamic range for effects and solid, if not pinpoint placement of
spatial sonic cues. In addition to doing a fine job with movies, unless
you are one of the few with a nine-channel system, the same amplifier
can drive additional zones. All in all, Onkyo's PA-MC5500 is a solid
performer and an even better value.
Additional Resources
• Read more multi-channel amplifier reviews by the staff at HomeTheaterReview.com.
• Search for speakers in our Floorstanding Speaker Review section.
• Look at dozens of AV receiver options.
