As many of you know, NuForce is one of the major players in Class D amplification for high-end audio applications (yeah, I realize that some of you feel that the words “Class D” and “high-end audio applications” don’t belong in the same sentence, but open your minds and work with me here). NuForce’s flagship monoblock amps have always been designated as “Reference 9” models, and I have been tracking their development ever since a set Ref 9 pre-production prototypes showed up on my doorstep more than four years ago. Over time, there have been a number of successive editions of the amplifier following roughly this sequence:
· Reference 9 V1 (only it wasn’t called the V1 at the time, since no one—not even the NuForce folks—realized that there would be successive versions).
· Reference 9 V1 Special Edition (NuForce’s Special Edition models are standard models equipped with beefed up power supplies and other audiophile-oriented tweaks).
· Reference 9 V2.
· Reference 9 V2 Special Edition.
· Reference 9 V3.
· Reference 9 V3 Special Edition (just released this Fall).
· …and along the way, NuForce was granted a patent for its “analog switching amplifier” circuit.
I’ve just received review samples of the new Reference 9 V3 SE amps (see photo), which are the subjects of this blog.
If one were to summarize reactions to the NuForce designs, strengths and weaknesses would probably get listed somewhat like this:
· Killer bass resulting, in part, from the incredibly high damping factor the NuForce circuit provides (these amps control woofer movements as few other do).
· Extremely open and transparent midrange—in my mind one of the unsung virtues of the NuForce design.
· Very good to excellent transient speed and definition.
· A tendency to present highs that can seem bright or overly lean (leading to what my colleague Wayne Garcia characterized as “highs under glass,” and that TAS Editor-in-Chief Robert Harley termed a “chalky coloration”). Personally, though, I found that the Reference 9 V2 SE made good progress toward solving this problem, which gives me hope that—when fully broken in—the Ref 9 V3 SE amps may do even better.
· A tendency toward a slightly “mechanical” rather than “fluid” sound.
Happily, though, the NuForce folks listen—not just to their own products, but also to trusted reviewers. As a result, one of the key thrusts behind the progression from the Reference 9 V1 to V2, and now to the V3, is an ongoing attempt to build on the sonic strengths above, while mitigating or eliminating the problems. With this thought in mind, NuForce describes the intended sonic attributes of its V3 SE circuit as follows:
“The Ref 9 V3SE adds refinement and delicacy to the already excellent-sounding Ref 9 V3. When used in less than the most revealing systems, the SE's advantages may not be fully realized. As excellent as the Ref 9 V3 is, the Ref 9 V3SE takes its strengths to an even higher level. These include:
· Sweeter highs, without any compromise in frequency extension.
· A smoother and more palpable midrange, while preserving the natural harmonic structure for which the Ref 9 V3 is famous. The Ref 9 V3SE is one of the few amplifiers in the world that does not impart a signature on the music. This results in a more natural and relaxed presentation.
· The bass remains the amp's huge strength. The Ref 9 V3 SE has same tightness and texture of the standard Ref 9 V3, but with a little more weight.
· The stage is more coherent and deeper.
In summary, the SE's sound is more neutral and liquid, with a more relaxed yet powerful soundstage presentation.”
Relative to the earlier V2 versions, the new V3 models (both standard and SE version) are rated to produce slightly less power at 8 ohms (175 W), but more power into 4 or 2-ohm loads (335 W).
Does the Ref 9 V3 SE live up to the claims NuForce makes for it? The honest answer is that I don’t know yet, since long experience with NuForce amps suggests to me that they’ll need a good bit of run-in time before their true sonic character is revealed (about 50-75 hours worth). But initial indicators are promising. I’m between stereo speaker (as opposed to multichannel speaker) reviews at the moment, so for the time being I’ve been using the Ref 9 V3 SE amps (in conjunction with NuForce’s Demian Martin-designed, two-chassis P-9 preamplifier) to drive my trusty pair of Magnepan MG 1.6 speakers.
My initial listening notes read something like this:
· Bass: as always, is excellent. It seems to me the R9V3SE amps are able to extract better (as in deeper, tighter, better defined) bass from my Maggies than any other amps I’ve tried.
· Mids: hard to say for sure at this stage, but I think they are somewhat more open and three-dimensional than those I heard from the R9V2SE. There’s a sense of soundstages being somewhat deeper and a fair amount wider. Also, the amps convey more of a sense of air being a “fluid medium” so that on some recordings I can much more clearly hear the sounds of instruments reverberating within their respective recording venues.
· Upper Mids/Highs: I’m still forming impressions. Straight out of their cartons, the amps struck me as sounding quite dry/bright, but things seem to be smoothing out nicely with additional playing time. I wouldn’t say the R9V3SE has achieved the promised treble “sweetness” just yet, but I’ll give it some time and see where we are 50 or so hours from now.
· One insight: while these certainly aren’t “wiry” or “metallic-sounding” amps, they are very revealing—so that I would say they are not particularly tolerant or forgiving of less than excellent program materials. But with really good records… they’re already pretty impressive.
Stay tuned for more comments over time and possibly a full-length review later on.
In the meantime, let me pass on one tip from NuForce VP Casey Ng for those of you conducting your own listening experiments with these amps. Casey suggests trying the amps with NuForce’s new “Focused Field” speaker cables (which is what I am doing). The cables are designed for general-purpose use with any type or brand of amplifier and speakers, but they do have a special shielding topology that the NuForce amps can (and Casey concedes that this is a more or less undocumented feature) leverage to achieve “a more three-dimensional and cleaner sound.” Interesting, no?