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Reviewer: Edgar Kramer
Source Digital: Metronome T-1i CD player
Preamp/Integrated: Supratek Sauvignon with NOS RCA and Bendix tubes
Amplifier: NuForce Reference 9 V2 Special Edition monoblocks
Speakers: Wilson Audio Specialties WATT/Puppy System 6
Cables: Cerious Technologies Digital; Harmonic Technology Magic Digital; Cerious Technologies; Harmonic Technology Magic and Truthlink Silver; DanA Digital Reference Silver; Eichmann eXpress 6 Series 2; Bocchino Audio Morning Glory interconnect cable; PSC Audio Pristine R30 Ribbon [on loan]; Cerious Technologies and Harmonic Technology PRO-9+ loudspeaker cables; Cerious Technologies AC; Harmonic Technology Fantasy; Shunyata Research Diamondback, Eichmann eXpress AC power cables; PSC Gold Power MKII AC cable [on loan]
Stands: Finite Elemente Pagoda Signature equipment racks
Powerline conditioning: PS Audio P-300 Power Plant (digital equipment only)
Sundry accessories: Burson Audio Buffer, Bright Star Audio IsoRock Reference 3, Bright Star Audio IsoRock 4 isolation platforms and BSA IsoNode feet; Bocchino Audio Mecado isolation diodes; Black Diamond Racing cones; Stillpoints ERS paper in strategic positions around DAC, Shakti On Lines; Densen CD demagnetizer; Auric Illuminator CD Treatment; ASC Tube Traps
Room size: 17' w x 35' d x 12' h in short wall setup, opens to adjoining kitchen
Review component retail: $5,000/pr

To where can a Blue Moon Award winning component progress when its product life span nears expiration? Having received several industry and customer accolades, the designers can find themselves in a dilemma. How to go about improving an obviously successful and extraordinary product? Do they leave well enough alone and ride the wave of product longevity? Do they reinvent tabula rasa style? Or do they throw caution to the wind and embark on a new evolutionary design journey?

These questions and dilemmas must have been of utter pertinence to the NuForce designers when evaluating a path of advancement for their successful Reference 9 flagship amplification product. And of course the design team would have, as a constant presence on the back of their minds, the added pressure of expectant forum dwellers and upgrade-anxious owners chomping at the bit.

In the end, NuForce chose an intelligent and moderate approach: they simply re-examined the successful platform and cunningly deduced potential improvements in key performance-related areas. After all, who better to implement another twist then the creators of their own twist on the emerging class D technology? After a considered technical effort, the long-awaited version two (V2) of the NuForce Reference 9 has been unleashed at the gates of the eagerly salivating audio community. Except this ain't no twist. This is serious stuff! Read on...

More Force to the NuForce
So as to meaningfully describe the V2 and to highlight new strengths or weaknesses, it is undoubtedly best to pit it against the excellence of its predecessor. And to even more accurately cover all bases and at NuForce's suggestion, it's even better to assess the two with a preamplifier that has been designed to work best with them. So for the duration of this exercise, out went my reference Supratek Sauvignon valve-based masterpiece and in came the new, Demian Martin (ex Spectral Audio) designed P9 preamplifier from NuForce. Although this is not a P9 review, I will briefly describe this quite superb unit. Built on the "dirty box, clean box" principle, this twin chassis full-featured preamp includes a host of single-ended inputs (including a HT bypass), balanced and single-ended outputs, LCD front panel read-out (with a rather awkward volume control logic with numeric values that were just as confused as I was), a unique octagonal all-metal remote control and D15 VGA-style umbilical that ties the two chassis together. And just to put this in perspective, I'll summarize the sound of the P9 by saying that it's one of the cleanest, most detailed and grainless preamps I've ever had the pleasure of not hearing. Oh, that means it's utterly transparent too. But conversely, a strength that really stands out is that the NuForce P9 preamplifier does bass better than any other this reviewer has ever heard. Period. Any recording containing any bass information, be it acoustic or electric as played in my system through the P9, just had me in palpitations. I'm talking majestic dynamic range, delicate detail, profound depth and gut-stroking power and punch. Say no more.

So this made for a superb platform by which to fairly and accurately dissect the amplifiers' sonic abilities. The Reference 9 V2 is identical to its predecessor almost absolutely except for the subtle V2 imprint on the bottom left hand corner of the face-plate. The two versions share the same high-quality connection options, balanced and single-ended, and the same simple yet elegant chassis. So, WBT NextGen RCA sockets and Eichmann cable pod binding posts. Input impedance is 45Kohm, THD+N is 0.03% at 1kHz at 10 watts, gain is 27dB and power bandwidth is -/+ 0.8dB from 100Hz to 20kHz with -0.5dB at 10Hz and -3dB at 60kHz.

Curious as to what technicalities were involved in the new version, I approached Jason Lim from NuForce for some enlightenment. After asking Jason many more design-type questions than appear here, Jason's responses surprisingly kept coming back to the three points below. Don't misunderstand, in no way was Jason avoiding issues. It's simply that his answers were reiterations of the core fundamental points, a testament to the two versions' ultimate similarities.

EK: Jason, what are the changes and technical/design differences between V1 and V2?

JL: We did not change the fundamental design from V1 to V2. This is what we came up with. There are several enhancements in V2 that bring about significant improvements in sonic quality when compared with V1, our 1st generation amplifier:

1. Heat management - by studying the thermal image of our V1 amplifier, we optimized the location of several heat-generating components to provide more even and faster heat dissipation. We also reversed the contact of the amplifier board heat sink to conduct heat to the top cover of the chassis instead of the bottom.
2. The differential feedback loop from the speaker is floating at the mid-point of the power supply. V2 further optimizes the bias point that allows the op amp to perform optimally, which resulted in an increase to the power output of the amplifier before it reaches the clipping point.
3. Layout and signal optimization - every signal's routing path and component placement is optimized to achieve the shortest path. RF emission and noise have been significantly reduced.

EK: What is the actual RMS power into 8 and 4 ohms now?

JL: 190W into 8 ohm and 300W into 4 ohm.

EK: Can you explain how you were able to reduce RF?

JL: See above.

EK: Anything else?

JL: We received a US patent in July 2007 for the self oscillating amplifier technology used in V1 and V2. The patent was applied in 2005.

That's it. Simple adjustments and refinements intelligently applied. So, what's to offer sonically?

Let's jump straight into the fray: the two generations are different sonically. Not chalk and cheese, more like cheddar and Brie. Where the original version had an extraordinary level of detail retrieval and attack on leading edges, the V2 mesmerizes by subtly furthering those traits. The subjective impression is of music being reproduced with utter faithfulness of detail while remaining totally accurate to the input signal. This is a fast and dynamic amplifier that seems to step out of the way and that has
matured and refined itself to the point where version one (V1 from now on) sounds marginally coarse by comparison. And, this will surprise you dear reader, I've mentioned these improvements based on the standard V2 as compared to the V1 flagship Special Edition.

The above is for starters. The next major difference between the two amps is that V2 has an immediately noticeable superior bass register from where it merges with the lower mids to the deepest depths your speakers can reproduce. It is tighter, faster and punchier.

In addition, the new amplifiers bring a sense of ease to the music. I would probably credit this to the blacker backgrounds the music seems to emanate from. I can describe this reviewer-speak characteristic as one where the silence between the notes is deeper, where the micro-dynamic information is less veiled by the noise floor of the amplifier. Secondly, the V2 sounds a tad smoother and less forward in the upper reaches of the midrange, making vocals in particular less Hi-Fi and more realistic.

So although these changes are noticeable, they aren't mind-blowingly so. They're worthwhile improvements that a revealing system, capable of highlighting subtleties, will drag out and expose and that a proud new owner will appreciate as a worthwhile justification for the dosh spent.

Specially for you
A few weeks later, I received the latest V2 Special Edition upgrade boards. So this meant goodbye to my V1 SE and hello to V2 SE. Prior to the upgrade, I held intensive auditions so as to fully reacquaint myself with the sonic prowess of the V1 SE. Then off it went to the Aussie importer and a few days later, the brand-spankin' (albeit in former V1 silver chassis with new face plate) NuForce Reference 9 V2 Special Edition monoblock amplifiers were delivered to my door.

On they went onto the superb Finite Elemente Pagode rack where I ran them in for several days before commencing listening sessions. First impressions were breathtaking. Standing out first and foremost was the increased level of macro dynamics. Where the previous version was very good in that respect -- albeit with superior dynamic contrast in the bass register when compared to the rest of the frequency range -- the V2 Special Edition retained the same power in the lows but married it with a massive increase in dynamic range in the midrange.

From A Perfect Circle's Thirteenth Step CD, "The Noose" is a well-produced melancholic landscape of sweeping guitars and keyboards counterpointed by the slamming drummer. Where the V1SE gloriously conveyed the angst in this track by clearly resolving the masses of instrumental lines, so did the V2SE but with an enhanced slam to the drum work, especially the snare drum and Maynard Keenan's vocals, both of which sounded uncannily real and sailed above the rest of the music's dynamic envelope. Don't interpret this as a sign of a forward sounding midband with a pushed forward and shallow stage. In fact, the second immediately noticeable sonic trait is a dramatic increase in stage depth. It is no exaggeration on my part to say that with the appropriate recordings, the depth of the soundstage appears to extend way beyond the front wall - further than any amp I've auditioned in my room for that matter. Width-wise, the V2SE only very marginally extends beyond the excellence that was offered by the V1SE.

The V2SE and for that matter the standard V2 somehow bring the listener closer to the soul of music. As airy-fairy as that sounds, it nevertheless applies to the sentiments and emotions experienced when listening to well-produced music of all genres. These are musical amps, no matter the style. The Special Edition version in particular dug so deep into recordings that minute details, the breaths, finger pops and brushes, creaks etc are all presented to the listener and exposed to the world. Other amplifiers fail to dig to the same extent, leaving these musical minutiae buried.

The Beautiful Girls' We're Already Gone CD is a well-produced bass 'n' drums slammer that
also contains some softer, more delicate reggae-ish moments. The V2SE's bass control and slam made this CD a whole lot of fun to listen to and its dexterity with the transients in toms and snare cut through the mix and into the listening space in an almost realistic facsimile while still allowing Mat McHugh's vocals to be easily discerned.

One of the stereotypical criticisms thrown at class D amplification is that, with acoustic instruments, they don't excel at reproducing harmonic content. Not quite the case with V1 but even less so with V2 and especially V2SE. Timbre is also spot on with these V2 amplifiers and, what's more, tone (as much as a neutral amplifier such as this can have) is a mixture of warm colors and textures and slamming sledge-hammer blows. Let's just put class D clichés to bed once and for all!

V for Victory
Once again, the NuForce engineers with Jason Lim at the helm have excelled at bringing to an anticipating market a tweaked-up redesign of an amplifier which was courageously engineered from the ground up. The V2 amplifiers surpass the V1 by way of their extended bass and additional dynamics. In the case of the Special Edition version, the aforementioned qualities are accompanied by superlative stage depth and an uncanny balance of smoothness, detail and slam in the midband and up.

The V2 amps stand up to any amplifier I've had in my system, irrespective of technology or price and I wouldn't be surprised if they did the same in yours.
Quality of packing: Strong double box cardboard with foam inserts and protective cloth bags
Reusability of packing: Can be reused
Ease of unpacking/repacking: Very easy
Condition of component received: As new
Completeness of delivery: All was it should be
Quality of owner's manual: Very good
Ease of assembly: None required
Website comments: Very informative with detailed background, theory, good photography, plenty of specifications but no pricing info
Warranty: 1 year
Human or web interactions: Prompt and professional
Pricing: Good value
Final comments & suggestions: Requires quality ancillaries
NuForce website