Simaudio MOON 600i v2 Stereo Integrated Amplifier Review
As I've grown older, and
presumably, wiser, I've come to appreciate more the significance of
anniversaries. Whether they be personal, such as birthdays and wedding
anniversaries, or professional (it occurs to me that I've been on the masthead
at Positive Feedback for nearly 20 years), these milestone
accomplishments resonate with me, due perhaps to their reinforcement of
continuity and longevity in a world of seeming constant flux and uncertainty.
Mayhap this explains the vicarious pleasure I experienced, learning earlier this
year of Simaudio's 40th anniversary. The Canadian-based high-end audio
manufacturer began its life as Sima Electronics, founded in 1980 by Victor Sima.
Sima's goal was to craft high-performance audio components with an emphasis on
sound quality as opposed to feature-laden frills. Over the next several years,
Sima Electronics changed its name to Simaudio and introduced, successively, the
Celeste and MOON lines. Simaudio later broadened its product offerings, bringing
to market the Evolution series of no-holds-barred high-end two-channel
components, as well as lifestyle-focused all-in-one products, and even dedicated
network streamers and headphone amplifiers.
My personal relationship with Simaudio extends back over two
decades, beginning with the MOON I-5 integrated amplifier. Over the course of
the ensuing years, I've owned numerous Simaudio components, with the MOON CD 5.3
CD player taking honors for longest-residing in my system, at 10 years.
Recognizing that the last Simaudio component I reviewed for Positive
Feedback was the Supernova CD player, back in 2006 (here),
I thought it time that I reacquainted myself with the brand. Given my penchant
for high-quality integrated amplifiers, I felt the 600i v2 would be a great
reintroduction to the MOON line.
The MOON 600i v2, introduced in 2018, is second from the top of Simaudio's integrated-amplifier lineup, and supplants the original 600i, which had previously been in production from 2010. In this day and age of Swiss-army-knife amplification, whereby integrateds frequently come bundled with digital-to-analog converters, streaming / network capabilities, phono stages, and headphone outputs, the 600i v2 represents something of an anomaly, being an analog-only component, with its focus strictly on line-level amplification duties.
Possessing fully-balanced, complementary circuitry from input to output, the 600i v2 integrated amplifier employs numerous Simaudio proprietary technologies. The 600i v2 utilizes a Simaudio-developed "Lynx" circuit to eliminate the global-feedback loop. By eschewing overall feedback in its amplifier stage, the MOON virtually eliminates transient-intermodulation distortion (which Simaudio's engineers believe to be more detrimental to an amplifier's sonic signature than the more-commonly-measured harmonic distortion). The Lynx circuit reduces interaction interference from the speaker to the amplifier, resulting in real-time amplification, a more accurate tonal rendition, and the elimination of phase errors associated with the application of global feedback. The 600i v2 also makes use of the Simaudio M-eVol2 volume control, which employs an R-2R resistor-ladder multiplying-digital-to-analog converter (MDAC) operating in the analog domain. The M-eVol2 is said to introduce no sonic degradation at any setting, while providing for very precise volume manipulation (down to 0.1 dB) across 530 steps. The 600i v2 is completely dual-mono in nature, from the preamplifier stage through to the power amplifier stage, even down to the power supply, with its twin 400VA toroidal power transformers and 80,000 microfarads of storage capacitance.
From a design perspective, the 600i v2 differs from the
original 600i in assimilating Simaudio's discoveries made in developing the
flagship 888 mono-block power amplifier. Simaudio endowed the 600i v2's power
supply with upgraded reservoir capacitors and made key changes in the
preamplifier stage, including the employment of new high-speed semiconductors.
The MOON 600i v2 integrated amplifier may not include digital
or phono accouterments, but it is nevertheless feature-laden. The 600i v2 allows
its owner to label inputs, offset gain up to 10 dB for any input, disable unused
inputs, and establish a maximum volume-level threshold for any input. The 600i
v2 also allows users to configure any input for home-theater pass-through
applications, whereby the volume control and associated gain stage are
Externally, the construction, build quality, and appearance of the 600i v2 befit its membership in Simaudio's upper range of product offerings. Measuring 18.75" wide by 4" high by 18.1" deep, and weighing 40 lbs, the 600i v2's external appearance is both elegant and bold. The front panel includes a large red dot-matrix display, which can be dimmed or turned off, as well as a chunky rotary knob that does double-duty as volume control and mechanism for the user to scroll through various software-configuration functions. The front panel also includes push-button controls for selecting inputs, adjusting balance, muting the output, adjusting the display illumination, and placing the amplifier in standby mode. Two additional buttons allow the user to access the setup menu and confirm settings. The supplied remote control duplicates these functions and includes several more that support Simaudio's digital products; the remote includes back-lighting and vibration features for ease-of-use in darkened environments (these battery-depleting functions can be disabled).
Around the back, the 600i v2 includes high-quality connectors
for line-level sources (one balanced XLR and four single-ended RCA), unbalanced
RCA preamp outputs, and two WBT five-way speaker-binding posts. The customary
IEC AC inlet is also present, along with several connectivity options for
linking the 600i v2 to other Simaudio components for centralizing control
through the amplifier.
The MOON 600i v2 integrated amplifier is a Class-AB design
that delivers 125 Watts per channel into an 8-Ohm load, doubling output to 250
Watts per channel into a 4-Ohm load. The first five watts of the 600i v2's
output are said to be in Class-A. Simaudio recommends that the 600i v2 break-in
for a minimum of 400 hours to achieve optimum performance, and that the
amplifier is powered up continuously (placing the 600i v2 into standby mode
disconnects the input stage and disables the display, leaving all preamplifier
and amplifier stages under power and warmed up).
During the course of the review period, my system comprised
the Marantz SA-10 SACD player, Focal Sopra 1 and Audio Physic Tempo
plus loudspeakers, Kimber Kable Select KS-1036 and Nordost Heimdall 2
interconnects, Kimber Monocle X and Nordost Heimdall 2 speaker cables, Audience
aR2p-T4 power conditioner, Au24 SE-i power cords and Hidden
Treasure AC outlet. All components were placed on a SolidSteel 6.2 Audio Table,
with Symposium Acoustics Rollerblock Jr HDSE footers. Acoustic treatments
were by GIK Acoustics.
MOON components are renowned for their lengthy break-in times,
and my previous experiences with Simaudio gear preconditioned me to expect a
trying period while the 600i v2 came on song, but in this I was pleasantly
surprised. The 600i v2 sounded good right out of the box, if a bit bland and
uninvolving. Within the first 100 hours, the amplifier opened up remarkably,
gaining cohesion and transparency. As the hours continued to pile up over the
ensuing weeks of continuous play, the 600i v2 improved incrementally, but absent
was the radical performance swings I'd witnessed with previous Simaudio
Once fully broken in, the Simaudio MOON 600i v2 integrated amplifier played music with beguiling levels of clarity and incisiveness. I was struck first and foremost by the unfettered nature of the 600i v2's spatial presentation. Never before have I experienced sonic imaging so utterly divorced from the loudspeakers as with the MOON amplifier in situ. Listening to "Train in the Distance" from Paul Simon's Hearts and Bones release (Warner 23942-2), I noted that the soundscape expanded in all directions, with the music swelling to fill the room. On the "Rene and Georgette Magritte With Their Dog After the War" cut from the same CD, the background vocals were convincingly in the room, positioned as they were behind Simon, whose upfront vocal was more dimensional and tangible than I'd ever witnessed. For this listener, who places a high degree of importance on imaging and soundstaging, the 600i v2's performance was revelatory.
Deborah Holland is known principally as songwriter and
vocalist for the late-1980s pop supergroup Animal Logic, which, aside from
Holland, comprised bassist Stanley Clarke and drummer Stewart Copeland. Holland
has also released several solo albums, which, in addition to being musically
exceptional, are also generally pristinely recorded. Holland's vocal on
"Bad Girl Once (Soccer Mom Now)" from her Bad Girl Once CD
(RageOn Records ROR0001) showcased the expressive and liquid nature of the 600i
v2's midrange. Holland's voice was rendered with a sense of unforced clarity
that, combined with a sublime truth-of-timbre, imbued the performance with a
profound sense of verisimilitude. Similarly, Jay Beckenstein's saxophone on the
title track of SproGyra's Morning Dance release (MCA Records
MCAD-37148) was reproduced with a sense of consummate naturalness, a perfect
amalgam of bite and burnished warmth, that enabled me to more easily suspend my
disbelief that Beckenstein wasn't actually playing in my room.
The Simaudio MOON 600i v2 was unparalleled in my experience at unraveling complex, multi-tracked mixes, lifting and segregating individual threads from the broader cacophony of instrumentation. "Ice Train" from Ashra's Correlations CD (Virgin CDV-2117), is a busy track, adding layer upon layer of guitar and synthesizer as the song builds to its climax. The 600i v2, more than any amplifier I've experienced, kept these disparate threads from becoming a jumbled morass. I was able to clearly pick out the individual lead lines from the myriad background sequencer, bass guitar, rhythm guitar, and percussion parts. A key contributor to the 600i v2's ability to navigate complex mixes was its uncanny sense of speed and rhythmic agility. The Simaudio integrated possessed a propulsive ease that drove the music forward in a very engaging way. The 600i v2 played and let go of musical notes in a captivating manner, making for very enthralling listening experiences. The myriad of sonic effects at the beginning of "The Waiting Room" from Genesis' The Lamb Lies Down on Broadway (Atlantic 82677-2) erupted in my room with explosive realism, and Tony Banks' frenetic synthesizer solo in "Riding the Scree" from the same album was rendered with a crystalline purity as the 600i v2 reproduced each note with a vivacity that had me locked into the performance.
The Simaudio 600i v2 integrated amplifier excelled at
reproducing treble instruments. Whether it was Bill Bruford's cymbal work on
"One More Red Nightmare" from King Crimson's Red CD (Inner
Knot KCSP 7) or the plangent violin on "Searching for Lambs" from
Steeleye Span's Tempted and Tried release (Shanachie 64020), the 600i
v2 reproduced the highest frequencies with air and seemingly limitless
extension, with no accompanying grit or glare. At the other end of the frequency
spectrum, the 600i v2 played back bass instrumentation with depth, tautness, and
true dynamic aplomb. If the 600i v2 could be considered to have any chinks in
its armor, however, it was in this aspect of its performance. When it came to
bass reproduction, the Simaudio integrated played it straight—there was no
euphony or warming up of the mid-bass or lower-midrange regions. Potential
purchasers seeking a warm or overly-full presentation may be put off by the
I was able to compare the Simaudio 600i v2 to two integrated
amplifiers, the AVM A3.2, retailing for $4800, and the conrad-johnson CA-150,
which retailed for $6500 prior to going out of production. The AVM A3.2's
class-D topology is very different from that of the class-AB MOON 600i v2.
Additionally, the AVM provides tone and loudness-compensation controls, as well
as the ability to add onboard digital-to-analog-converter, phono-stage, and/or
FM-tuner modules. The AVM is rated to deliver 100 watts per channel into an
8-Ohm load. The A3.2 has been my reference amplifier for the past two years,
primarily on account of its uncanny transparency, resolution, and ability to get
out of the way of the music. The 600i v2, however, bettered the A3.2 by virtue
of being even more transparent, more resolving, and, at the same time, more
communicative and involving. More extended at both frequency extremes, the 600i
v2 also surpassed the A3.2 with its expressive midrange reproduction. The
conrad-johnson CA150 proved to be an interesting counterpoint to the Simaudio
600i v2. The CA150 combines a passive linestage with a high-sensitivity class-AB
power amplifier. Like the Simaudio, the conrad-johnson does not possess a phono
stage or onboard digital capabilities. The CA150's power rating is a comparable
135 watts per channel into an 8-Ohm load. Sonically, the CA150 possessed a
liquid, golden midrange that contrasted with the 600i v2 more immediate and
expressive presentation. The CA150's soundstage presented itself further behind
the speakers, but lacked the 600i v2's inimitable ability to float images
independent of each other and the loudspeakers. Dynamics were better rendered
via the 600i v2, which was also more robust at the frequency extremes. Of
significant note, however, is the 600i v2's overall veracity and sheer lack of
artifice, which not only exceeded the performance envelope of the AVM and
conrad-johnson integrateds, but also that of every amplifier I can recall
experiencing in my system.
Over the course of nearly two decades in my tenure as reviewer
for Positive Feedback, I've amassed considerable experience with
integrated amplifiers, having owned, auditioned, or reviewed numerous models
during that time. Even within the context of that breadth of experience, the
Simaudio 600i v2 strikes me as a truly special performer. With its bold
aesthetics and built-to-last-a-lifetime construction, the 600i v2 exudes
high-end class. It's the 600i v2's sonics, however, that place it in the
deserved ranks of the upper echelon of integrated amplifiers. Transparent and
resolving, dynamic and expressive, the Simaudio 600i v2 integrated's immediacy
and musical involvement are unparalleled in my experience. It's the best I've