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Armed with an 8ft pair of Zu Wylde leads, out came the hi-level factory jumpers, in went the low-level connections tapped from either the output of the Red Wine Audio Signature 30.2 or the 6H30 outputs of my Supratek Cabernet Dual preamp. The latter has far more gain than the 101D sockets so the Hypex attenuators had to sit lower. Regardless, the 6H30 feed was superior. That's of course why my unusual bi-amp preamp allocates its tubes as it does. The direct-heated 101D are unbeatable in the midrange and treble but quite weak down low. The 6H30's stouter current delivery and drier character excels in the bass but isn't nearly as refined and magical in the vocal and treble bands.


Even so, I wasn't fully prepared for the nice improvements of this hookup. In my context, this was the setup. Rather than granting undue space to an issue that will vary with hardware -- and which remains open-ended with the options the built-in flexibility accounts for and encourages to experiment with -- let's discuss an important design decision Zu has made for bass quality: sealed alignments.


The texture and control of sealed bass, at least to these ears, tend to be in a different league than vented alignments. By the very definition of how ports operate, they are resonant and ringy. The Xavian XN360s with their dual ScanSpeak Revelator woofers slot load into a down-firing port that faces an integral plinth. They demonstrate that difference well. Where the Zu bass is tight, linear, controlled and integrated with the overall character, the ported alignment is fat, fuzzy, bloated and overdone.

Ported alignments increase amplitude and attenuate shallower. Purely from a quantity perspective, they make more (bass) from less (driver hardware). That's why they're popular with speaker makers. Without equalization, the dual sealed 10s in the Presence wouldn't go as low as the dual ported 7s in the Xavians. But the Eminence 10s are certainly capable of lower and louder. They merely need to be goosed to do so. Hence Zu's default recommendation for the 6dB @ 20Hz setting. Minus this back story, it'd suggest immature disco fever. As it stands, this equalization is perfectly appropriate for the sealed loading. Without it, the Presence would require easily double its present woofer artillery. Loud and (unfortunately not very) clear, it's the Xavians which are the boomers.

Where the Presence textures and traits are finely honed and linear from top to bottom, the XN360, at least during its first weeks, betrays discontinuity and a very different character and behavior in the bass. While the Revelators in the Czech speakers are undeniably premium issue, they seem compromised in their partnership to a different -- and apparently forced -- vented loading scheme tuned to 25Hz. Whereas the Eminence-based Zu drivers would seem comparatively over-shadowed by Scandinavian specialist reputation, their de facto in-room resolution actually seems higher because there's no electoral smear campaign from the bass system. We'll return to resolution momentarily. Let's first hammer home a consequence of the above; specifically that unless your mind stopped keeping tabs, you'll have done the math by now to realize that "upgrading" the Hypex amps by offboarding removes their equalization advantage. Unless your amp was strangely designed with a built-in lift at 20Hz -- it won't be -- you'd short-change yourself of bass extension. That's why Zu's optional outboard solution too will retain this EQ functionality and in fact expand over what the plate amps can package. In short, don't snub these plate amps because they're plate amps. Bruno Putzeys at Hypex is one of the smartest designers presently working in class D and his solution seems like the genuine article for this application.

Which systematically returns us to resolution - the ability to see far into the soundstage because nothing clumps up. I'm not a speaker designer but there's every indication that the high-tolerance parts matching at Zu today is directly responsible for this enhanced perspective of great depth. An interrelated effect is the normalization of images to realistic sizes, eliminating ghost halos or fainter duplicates. Image outlines define themselves and in turn, draw inwards and shrink. They cast off the bigger but less acute transitional zones which mimic the Photoshop feathering command whereby outlines bleed subtly into the surroundings. Yet neither the opposite occurs. There is no 'sharpen edges' command to pixilate the outlines for that forceful relief that actually brightens the transition points between object and background (or space and silence in our audio case).


All this is very non-spectacular. The key is that you can listen quietly without finding fine detail diminish. When you prime the pump, things only get louder, not physically bigger. One of my favorite late-night CDs is Hayalgibi 2 [Akustik]. On it, kanun virtuoso Göksel Baktagir leads a trio including Middle-Eastern violin (keman) and piano. The super-fine harmonic alterations a very softly drawn bow elicits from the violin in semi flageolet conjoined by the more piquant string plucks from the kanun and the hammers of the piano are an endlessly fascinating meditation on subtleties. It's like gossamer tendrils intertwining, Indian Summer spider webs floating on the wind - ephemeral stuff that takes finesse, not brute force to render completely.
Revisiting Hayalgibi 2 the other evening, I was struck by just how quiet everything seemed and how pure and crystalline the harmonic nuances were and how sonorous the occasional power chord on the piano. This was high resolution but supremely relaxed and easy. No heightened contrasting was necessary to let the mind hold the space in which decay trails could vanish. Following those trails along the dimensional depth of the soundstage, the mind then expanded into a slightly altered state. It's sensible to believe that a quieter cabinet would contribute to this and that more stringent parts matching would increase accuracy and precision. That's certainly how it sounds. Just as importantly, there's more finesse to the treble. On the Anna-Marie Jopek disc Upojenie with Pat Metheny, one hears more of the excitation of metal molecules when the drummer alights multiple cymbals at once.
Back to realism and reality. There of course is a limit to bass power here. It's obvious that one could overload the physical structure of this speaker by playing too loud in too large a room with the bass EQ setting as recommended. The solution then is to turn down the volume; decrease the EQ some or go for a flat response; or get a bigger speaker like the Definition 2 which offers twice the fire power down low. There is no cheating the laws of Physics. If it's full-range response you're after from a compact cabinet that's sealed for best group delay response -- and if, in the process, you're applying significant bass boost -- you can't energize too large a space or you'll create too much internal pressurization in the enclosure. That causes congestion and distortion. For a space of 18' x 24' x 10 like mine, the Presence recipe is tailor-made. More even than the older Definition before, it really manifests the Zuist plea of "the most speaker in the smallest possible footprint for a fair price".
Timing isn't talked about enough in hifi. Yet even heavily engineering-driven outfits like Wilson Audio adopt time alignment provisions for top models and take pains to minimize group delay. While other design objectives may have precedence -- i.e. non-conformity there is more objectionable -- once those are accounted for, 'good' or 'poor' timing do become quite audible. Those familiar with Roy Johnson's Green Mountain Audio speakers will know whereof I speak. With them, you can deliberately screw up timing to hear the difference. A lot of sharpness in hifi results from time delay where the leading edge information from the treble unit arrives too early. As Roy Johnson demonstrated to me in Arroyo Seco, correct timing reduces sibilance and makes things sweeter. Siltech's Pantheon XXV presentation in Arnhem made a similar point. When the electrostatic tweeter was properly aligned, focus improved.
The Presence sounds like a speaker with good timing and the head array appears to be physically time-aligned, with the minimum-phase 1st-order high-pass on the tweeter the appropriate filter in this context. While it's not clear whether the two woofers are physically time-aligned with the wide-bander (unless the latter's voice coil assembly is a lot farther behind the cone than the woofers', they're not), the bass system on the front rather than Definition-style rear baffle appears to benefit overall coherence. In short, rhythmic snap and keen articulation on percussive events such as pepper Tulku's A Universe to come and Mercan Dede's Nefes are core strengths of the Presence concept and improved over my Def Pros. While the 4wpc Trafomatic The Experience One 2A3 SET with JJ 2A3-40s had plenty of muscle for spirited sessions, upper midbass transients over the widebander weren't quite as potent as over the higher-power Melody push/pull amp or Vinnie's battery T. Still, Theo as I call the piece is an astonishingly good budget amp, electrically and mechanically quiet and more than up for long-term Presence duty.

The wrap
Definition 2 excepted which I haven't heard, the Presence is the best speaker yet from this Ogden speaker house. Best means, the most balanced and refined. It's also the physically most attractive. Its dimensions and form factor seem very classically proportioned from the front. Unlike some high performance speakers, the Presence is quite unfussy about partnering amplifiers. The $,2500 RWA Signature 30.2 is a particularly good match which brings a pair of widebander speakers with active stereo subs and main (integrated) amplifier in for 10 grand and change. Add a good front end like a Raysonic CD168 or Opera Consonance Reference Linear 2.2 and without completely going off the deep end -- no matter how you cut it, this is serious money -- you'll have a very high-level system that communicates even at the whisper levels where most speakers fail to deliver; rocks out when asked to; is flexible to help you tailor the response; can be customized on finish... as Stereophile's legend Sam Tellig would put it, there's an awful lot of there there. Hear hear.

PS:
Having accepted this assignment as merely the latest in quite a queue of prior Zu reviews, I had a goodly notion on what to expect. That and psychology led me to deliberately reign in personal excitement. It's sad but true that repeat raves by one writer about one brand accomplish the exact opposite of what perfectly honest enthusiasm would want - to turn on complete strangers to a really fine thing. That's exactly what we have here in my estimation. In fact, finer -- more finessed and advanced -- than expected. But to appreciate that, you really must listen for yourself. With a generous satisfaction guarantee, Zu has made it easy. As a big boy owner, I would advise that unless your room was truly large and your SPLs very happy, not to assume that the top model was mandatory. I'd pocket the difference or use it on something like the Signature 30.2 or Melody I2A3. Having been on the reviewing beat for about 7 years -- not an eternity but based on products processed, an intensely busy time with a goodly dose of hifalutin encounters -- I don't believe anyone not obsessed beyond reason (or somehow predisposed against Zu) would want or need more than the Presence. While that's a conservative statement, there's more to it than pinstripes and wing tips. More too than crass 'tude and libertine disregard for solid design basics. No, for its particular design brief, the Presence is way solid. It's like, dialed, dude! As such, the Presence is deliverance from certain preconceptions the Zu brand has been fighting...
Quality of packing: Stout cardboard with hard foam separators protecting the speaker from all sides. Cabinet is wrapped in shrink wrap.
Reusability of packing: Yes.
Ease of unpacking/repacking: Easy..
Condition of component received: Perfect.
Completeness of delivery: Includes 2 x Birth power cords, 6 pointy spikes, 6 dull spikes, copper metal polish, tack cloth, full-line Zu lit, preinstalled high-level jumpers.
Quality of owner's manual: See above - nothing on this model yet.
Website comments: A work in progress which needs more hard info on design objectives and particular technical implementations thereof. The company puts far more thought and effort into its products than are communicated.
Warranty: Limited 5-year parts and labor warranty to original owner.
Usage conditions: 16-ohm main input and high sensitivity are super friendly to low-power triodes. For best attacks, 15 watts are good to have but 2-watt 45 amps will produce all the sound pressures you want. Do not run the low-level Hypex inputs with the high-level jumpers installed. Engage 6dB @ 20Hz EQ as the default start setting to compensate for the sealed alignment's native roll off.
Human interactions: Exceptionally helpful. Zu is an enthusiast bunch always willing to go the extra mile. Their 60-day home trial option shows both confidence in their products and appreciation for a customer's need to be sure.
Zu Audio website