Simaudio is a Canadian manufacturer, located in Boucherville, Quebec. They should need no introduction to readers of this publication.  For those requiring one, please read our reviews of the W-3  and W-5 power amplifiers.  Simaudio has been in business for over 20 years, and in the last few they have gained much international recognition.  Their products compete for audiophile consumer purchases with the likes of Jeff Rowland, Mark Levinson, Classé, and Pass Labs -- the cream of the crop of solid-state amplification.

The Simaudio Moon W-10s are 750-watt monoblocks (into 8 ohms, virtually doubling to 1400 watts into 4 ohms).  They run 'Class A' output for the first 10 watts and then 'Class A/B' thereafter.  As with all Moon amplifiers, they are a true balanced differential amplifier using a ‘no overall feedback’ design, with just a touch of local negative feedback in the output stage for stability.  Simaudio states these result in real-time amplification and more accurate musical reproduction.  With precision matched bipolar output devices, a high damping factor and two custom toroidal 1 Kva transformers per amplifier, the W-10s demand to be taken seriously.

The W-10s look like a pair of W-5s, with a classy small badge (now smaller than earlier models as shown in the W-3 and W-5 reviews), a single blue light on the thick faceplate, curved heat sinks running the length of both sides of the amplifier and well designed handles running almost the length of the amplifier on each side; the handles are designed to incorporate four adjustable steel cone feet. At 75 lbs. per amplifier, the handles are clearly not an afterthought. The cone feet minimize detrimental external vibrations. Standard finish offers black with white handles, but the faceplate can be ordered in silver.  High quality WBT input and output connectors on the back make for easy hookup.  The main power switch and standby power button are located on the back.  These amplifiers are designed to be left on at all times, and with only 48 watts power consumption per amplifier at idle, combined with a 10 year warranty to the first purchaser, I can see no reason not to do so. 

Unpacking the amps was straightforward with the handles showing their mettle immediately.  Each amp was plugged into a separate, dedicated 15-amp line using 20-amp wire (amps of this size will always appreciate this dedication). The inputs are a little different than most power amps and deserve examination. Each amplifier has one balanced (XLR) and two RCA connectors, one RCA for normal phase and the other for inverted phase. If an RCA connector is to be used from the preamp, the unused input connector on the amp (usually the out of phase connector) should have the shorting plug installed.  If balanced (XLR) connectors are used between the preamp and W-10s, the shorting plugs should be removed.  The amplifier should be turned off to remove or install the shorting plugs. To all W-3 and W-5 owners using balanced interconnects who have the shorting plugs still in, please take the plugs out, too (when the amplifier is off).  Your amp will definitely sound better this way.  My thanks go to the distributor for clarifying this point. 

After reading the manual, unpacking, and connecting, I turned them on right away for a quick listen.  Cold out of the box they were as expected, so I left them to cook.  Five hours later, they were improving, but by then it was 3:00 a.m. Bedtime! Not an easy place to go with such beautiful amps warming up.  After 24 hours they were still noticeably improving, and four days after initial turn on (100 hours) they started singing. Happily, Simaudio burns in their amplifiers for 24 hours before shipping. Listening notes and the review were completed only after the 100-hour break in AUDIOPHILIA requires of all its review equipment.

The W10s were first installed for the woofers of my Infinity Beta loudspeakers. These are a four chassis speaker system with planars for the mids and highs and four 12" woofers a side in separate enclosures.  They have an impedance of 4 ohms, a difficult load to control for some amplifiers.  The Betas are very component sensitive, and depending on what is placed upstream, they can vary from untamable to simply stunning.  Infinity designed them using a solid state/tube hybrid preamplifier, tube amplification for the planars and solid-state amplification for the woofers. 

I have been swapping amps for the woofers for a while now, trying to tame them, but none controlled them like the W-10s.  These amplifiers have articulation, speed, and musicality.  Those who own Infinity Betas enjoy a full frequency sound, and the frequency response chez nous can plumb 15Hz.  If the woofers are hooked up to an amplifier that can't control them, the bass will bloom unnaturally and lose focus. The W10s tightened things up considerably in the lower octaves, giving an increased sense of timing and pace.  Listening to Terry Evans sing ‘Get your lies straight’ from Blues For Thought (Pointblank 39064 2 0) was a real eye and ear opener. The bass impact was deeper, faster and tighter than I have previously experienced from this great cut.  The lower octaves had less overhang than before.  On Sam McClain's Where you been so long from Sledgehammer Soul and Down Home Blues (Audioquest AQ 1042), the bass again improved -- the entire sound of the system became much more refined across the frequency spectrum, more than I thought a woofer amp upgrade could do.  Writing was becoming a chore when compared to the simple act of listening to these exceptional amplifiers. Yet, the deadline loomed! So, onward and upward to Patricia Barber. :p>

Barber’s Café Blue (FIM010 gold CD) was even more illuminating – the drum set sound on the infamous Too Rich For My Blood had me in awe. On Ode to Billy Joe I could visualize the plucking of the bassist's strings.  This recording was previously under-controlled in my system, but the added weight, body, and detail left me very impressed. Listening to Holly Cole's Get Out Of Town from Don't Smoke In Bed (Alert CZ2 81020) revealed the same deep, tight bass. However, bass was not alone in its refulgence -- the improvement in the resonance of the piano attacks, the way each note just floated in the air, and the added delicacy of the breath on the harmonica was revealed in absolutely first class sound. 

Associated Components Analogue: SOTA Star Sapphire/SME V/Benz H2 Digital: Theta Miles CD (for transport), Theta Gen Va 24/96 DAC Preamplifier: Audio Research Reference 1, ARC PH-2 phono preamp  Power Amplifiers: ARC M300 Mk. II  Tuner: McIntosh MR7083 Loudspeakers: Infinity IRS Beta Cables: Interconnects: XLO Signature 2.1 balanced , 1.1 RCAs Loudspeaker: XLO Signature 5.1 for front end and planars, 1 interconnect and 5 speaker wire for woofer connections, Synergistic AC Master coupler power cords

Another example of control provided by the Moons was on Steppenwolf's Born to Be Wild and Magic Carpet Ride (probably the first and last time this recording will be used in an audiophile equipment review) [get thee to NYC’s A Classical Record – Ed].  Every time I have heard this on a full frequency speaker, the bass was out of control, leading me to the conclusion that it was recorded that way. I was wrong! The grip on the woofers once again had them behaving and me dancing around my listening room, realizing that all my vintage rock LPs just improved in a magnitude for which I was unprepared. Happy times are here again!

This was not just the W-10s I was hearing, although they were clearly responsible for this outstanding transformation. They simply got out of the way of the music more than any other amp I have used in this configuration. As such, I heard more of the ‘flavor’ of upstream components than ever before.

I hooked up the W-10s to the planars (by way of the excellent WBT connectors) with XLO signature interconnects and speaker wire.  The sound was very precise, articulate, and transparent.  The increased dynamics were very pleasing.  It was not hard or brittle as some familiar with this speaker might assume.  It did not produce the width and depth of soundstage of the Audio Research M300 Mk IIs, the result of the amps, planars, and wires all leaning a smidgen to the same side of reality. I replaced the XLO with Cardas Golden Hexlink 5C and tried again.  There was the soundstage I had lost, not quite to the same degree as the Audio Research tube amps, but nonetheless excellent.  The delicate decay of acoustic notes was almost tactile. Yep, musicians were in the room and I did not want them to leave.  The soundfield made me feel as if I was sitting closer to them and hearing far less effect from my room reflections.  The W-10s really excelled in this regard -- in fact, they exceeded my expectations of how they would perform in this difficult test. No other solid-state amplifier I have heard in my system worked so well.

If making music is an art, then reproducing music is also.  Manufacturers as passionate about music as the teams at Simaudio have their own take on what sounds correct, and this is what makes differences between audiophile components so intriguing.  It is also part of what makes being an audiophile so much fun. Which brings me to the question: Are these amplifiers for you?  Your listening preferences, biases, and the synergy of such along with the rest of your system are all things to be considered with any amplifier in this price range.  I know that they are one of the finest pair of solid-state amplifiers I have heard, and not much near its price range comes close to matching its transparency, control, dynamics and musicality.  The W-10s do not sound hard, analytical, cold or sterile, as some tube die-hards consider much of the solid-state world (the '70's are over, after all), they simply sound more like what they are fed. They are accurate, but unlike lesser solid-state equipment, they do let subtle cues through. And be sure, those cues are unscathed or modified. 

At US$10,000.00, the Moon W-10s are not cheap. They did, however, transform my system into a coherent family. There is no substitute for kilowatts, especially when they are as exceptionally well designed as the W-10's.  Whether adding the W-10s as part of the amplification chain or using the pair as the only source for power, I gave them my highest recommendation – I purchased them.