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It does swing. Right now consider the clues I planted earlier. Like in a whodunit, they already put our suspect in the frame. If you followed my FirstWatt writeups, you know that of their regular voltage source designs, the F5 is the most crystallized, lit-up and coolest. It's the champion of DC-coupled wide bandwidth reflexes. The M2 introduces deliberate 'Mosfet mist' plus transformer voltage gain. That mellows transients and fleshes out midband and treble a bit. Having called the M2 a better match should have identified the Ampeggio's core character as very fast and texturally lean. It thus benefits from a strategic but small tone density injection. The F5 in turn over-emphasized transient incisiveness. This very linear low-distortion amplifier confirmed that in the critical presence region, the very well-behaved Ampeggio was probably still up a gently contoured 2dB. (Limited midband information does exit the horn mouth. This was deemed superior over installing line-damping material for passing only the low frequencies as any kind of fill "killed the sound".) The presence region is excitingly direct without wanting a cruel flash light on it. There's no inherent shoutiness over a narrow peaky range, just a well-integrated small reminder that widebanders do typically emphasize this band to some extent.

Voxativ at the Taipei Hi-End Show 2010 - coverage here

Having called the Yamamoto 300B SET less ideal suggested a few things. Ampeggio's resolution, timing precision and overall lucidity are too high to tolerate coalescent 2nd-order THD effects. And, this speaker is not lean enough to require that level of enhancement. With the designer and yours truly favoring my IT-coupled EL84 monos over the M2 as a very close second, a carefully controlled injection of tube textures with high linearity and wide bandwidth seemed like the golden ticket. This doesn't eliminate transistors but demands very high sophistication if you want to play in the sand. FirstWatt's F3, J2 and M2 seem ideal.

This speaker [at right in pre-Schimmel veneer] proved superbly transparent to tube rolling. Over the A-09S, it clearly telegraphed the increased treble energy of the Synergy Hifi valves; the gentler flair, softer bass and deeper colors of the TJ SE; and the higher damping of the EAT and EML XLR. From my amp options, it simply turned out that the lower THD, higher bandwidth and greater linearity of the Russian military 6P14P-EV in push/pull class A with two local NFB loops—0.3dB between driver and output tubes through the interstage transformer, 4dB between output tubes and output transformer—held the ace of transistor and tube virtues.

From the above, you should be able to triangulate with a high-efficiency speaker house whose products I've reviewed extensively. The Zu house sound is meaty, dynamically feisty and boisterous, overall dark and not that detailed. In the FirstWatt catalogue, I'd mate Zu with the F5 or F1 for best bass control, reflexes and top-end extension. By comparison, the lighter more resolved Voxativ is far closer to the Lowther aesthetic, albeit with four key differences: no shout; superior dynamics; smoother treble; and real bass. Call it a Lowther sound without the usual compromises. That profiling gets you into the ball park.

If not augmented by woofers, Lowthers tend to be back-horn loaded for the obvious nether reasons. Back horns that are ambitious about bass extension grow quite sizable then. Outside decor considerations, big rear horns often also entail drag. Focus is somewhat amorphous and bass always lags behind the beat. Unlike most back-loaded horns, Ampeggio's bass is very much on time. Plus, it's texturally taut rather than loose. On a whole that's arguably the greatest progress Voxativ contributes to the single-driver genre. It explains why this speaker really does have that swing.

Needless to say, the cone area of the AC-3X couldn't displace the kind of air the triple 8-inchers in my reference speakers do. While bass extension, agility and definition were class-leading for this breed, body-slam viscerality of big drums or Victor Wooten/Marcus Miller-type slap bass didn't match the violence of dedicated paralleled woofers. Nor power at 25Hz. That's obvious. By the same token, the Ampeggio's bass really was on the money - arguably more so than many conventional speakers whose phase shifts in the low end undermine their beat fidelity.

The Ampeggio's top end was nearly the equal of my resonator-enhanced Dynaudio Esotar clone in the ASI Tango R. One of my telltale tests is "Promenade" from Vassili Tsabropolous' Melos [ECM]. Very well recorded, its struck triangles flare up like flashing beacons in the dark. Only the best treble systems will track their decays to the end. While Franck Tchang's speaker had more of the very highest Platinum overtones, the old-fashioned whizzer cone let the tones ring out just as long, the initial rise of struck metal flare up just as sharply. This was unexpected to put it mildly.

Granted, I'm no longer a bat-eared youngster. My hearing probably cuts out between 16 and 17kHz. While a 20-something might judge the Ampeggio's stratosphere different, chances are that type of listener wouldn't allocate 16G on a speaker with a single driver. For those sufficiently liquid who'd be drawn to this esoteric concept in the first place because they've tired of more conventional solutions... to such customers, Voxativ's treble is very much complete.

Even so, all this leaves us with one very big question. Attempting to answer it means that we first have to define certain very specific but arguably 'esoteric' performance parameters. The question is whether Ampeggio's performance could be duplicated by more conventional and/or cheaper means which would throw into the bargain more 40 - 80Hz displacement and likely get one closer to 20Hz. On actual performance, is the single-driver concept justifiable and more advantageous than a minimum-phase full-range speaker of Franck Tchang caliber or the far cheaper Anthony Gallo Reference 3.5 for example?

Is there something unique to the Voxativ that can't be had elsewhere? If so, is it fundamental enough to silence other considerations? To state it unmistakably, Voxativ's Ampeggio is the first widebander in my acquaintance to even beg that question in its fullness. Nothing else in this category previously had been this free of compromise to become an unconditionally valid counter option. Zu lacks upper-band resolution to play in these leagues (and by definition theirs aren't pure single-driver designs). Solo Lowthers by Rethm had special virtues which were overshadowed by obvious shortcomings in the overall balance. The top PHY 12-incher absolutely needs one if not two auxiliary tweeters. And so on. Audiophiles with sufficient experience and honesty would admit that for a single-driver speaker to even get to this place—and quite regardless of how one might ultimately answer 'the big question'—is a huge accomplishment. It's a massive accolade. With the Ampeggio, Inès Adler demonstrates how a single driver can really do it all. Beyond exotic appeal however, why would one go after her speaker over a first-rate conventional option? What are the special benefits?