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Reviewer: Les Turoczi
Digital sources: Naim CD2 CDP; Modwright Sony 999ES Signature Truth CDP; Sony PCM R500 DAT deck; Sound Devices 744T HD Digital Recorder
Analog Source: Linn Sondek LP 12 fully upgraded with Lingo, Cirkus, Trampolin etc.; Naim ARO arm; Spectral moving-coil MCIIB cartridge; ARC PH3SE phono stage; Magnum Dynalab Etude FM tuner
Preamp: Audio Research REF 1 line stage, Consonance Ref 1.3 TVC [in for review]
Power Amp: McCormack DNA 500; Electron Kinetics Eagle 400 monoblocks on woofers
Speakers: DeVore Gibbon 8
Cables/Wires: Various sets of interconnects, speaker wires and power cords from Zu Cable
Power: Dedicated power lines; BPT BP-3.5 Signature Plus power conditioner
Accessories: "The Base" platforms; Symposium Svelte Shelves, Point Pods and Fat Padz [on loan]; Walker Audio Extreme SST Silver Treatment and Reference HDL Mk.II links
Room size: 14' by 23' with 8' ceiling, speakers set up on short wall; carpeted concrete flooring
Review component retail: $9,000/pr for Definition Pro; $1,000 for Rane PEQ55
If you have not heard about Zu Cable products, you might be living in a cave or out beyond the fringe. Here at 6moons, many reviews and previews give well-deserved praise to their loudspeakers and wires/cables, which rank strongly both for performance and value. As others begin to discover these varied, well-designed, carefully executed forms of audio equipment, the good news should spread even further. I hope that my evaluation of the Def Pro loudspeaker system will help explain the evolution of this statement product as well as disseminate the good word. I would be sorely remiss not to heartily suggest consulting the fine review of the original Definitions Mk.1.5 penned by Srajan in August 2005; he also previewed the Def Pros in October 2005 [his personal pair above]. Certainly do check those out before going any further here, since I consider both articles essential reading. They provide background along with deep insights into the speaker design, the company philosophy and the unique place this loudspeaker occupies in today's marketplace.

My first direct exposure to the full range of these products occurred last summer in Easton, Pennsylvania during one of the Zu road shows, for which these folks have garnered a fine reputation. In addition to hearing their offerings, I was able to speak to both Adam Decaria and Sean Casey, the principals behind this operation. Aside from the expected audio activities, which were being handled in a casual but effective fashion, I was struck by the low key, unpretentious approach unfolding during the demo. In addition to being audio equipment designers and manufacturers, both Zuists are serious music lovers and all around terrific guys. They made everyone feel welcome, comfortable and ready to have fun. All of this certainly whet my whistle to want to know more about Zu, and thus this story.

After a few additional inquiries into the speaker side of Zu, I discovered that they were planning to release a "Pro" version of their Definition speaker system. Instead of the standard self-powered configuration, the Pro Def would come with a highly flexible parametric equalizer from Rane and no bass amplification. This would allow for extensive tweaking for amps, for room adaptation as well as for musical styles, tastes and other twists. All of this made good sense, so after consulting with Srajan, it was clear sailing for me to obtain a review pair and explore these fertile fields.

Nuts and bolts of things
The size of the Def Pro is rather surprising once you consider all of what is housed in the handsome monolithic cabinet. While managing to have a footprint of only 12.8' by 12.5" and a height of 49", each 120 lb. enclosure contains seven drivers, four of which occupy the majority of the back panel. I must say that the gorgeous blue-colored samples which arrived at my place have impressed everyone who has seen and heard these babies. A typical comment usually sounds something like "it's hard to believe that so much excellent sound can come from such a relatively compact and good-looking package". I fully agree. Naturally, color choice is wide and custom finishes can be arranged, at an extra fee, after consulting the Zuists [Srajan's "Taos custom" version below for an example].

The driver compliment is arranged such that two 10" drivers on the front of the enclosure cover a very wide frequency range, namely 50Hz to 10KHz. Then a centralized "super" tweeter takes over and handles the rest of the highs out to deep space. Interestingly, these 10" cones cover about 90% of the audible range and do so without a crossover in the path. On the rear of the sealed enclosure sit the previously noted four 10" bass drivers which cover from about 40Hz down to 16Hz. Two pairs of binding posts at the bottom of the back panel allow for connection to the two sets of amplifiers needed for this biamplified pro configuration. Spiking is easy to arrange and requisite to extracting all the goodness inherent here. For those who prefer low-powered amplifiers, the efficiency is very high, clocking in at 101dB [1w/1m]. I can happily say that using high-powered amps is not a problem either (I used the mighty McCormack DNA-500 on the frontal array). The user's manual covers the basic loudspeaker system details very nicely and the Zuists are working on preparing supplemental information for establishing a simplified baseline for initially configuring the Rane EQ on the rear-firing 40Hz-and-lower array. Everything I have seen and touched bespeaks excellence in both execution and design.

Use of the Rane PEQ55 external pro-level DSP parametric equalizer makes for an excellent match to all of the other design considerations in this package. This device is festooned with knobs, sliders, switches and other doodads, but that is intrinsic to being able to fine tune the bass performance of the overall system. Fortunately, Sean Casey, as one of the head Zuists, did help me by phone to get the initial settings to the point of decent sound in my room, but there was yet more to extract. I was very pleased when Sean indicated that he could visit here after an additional period of speaker burn-in took place. That session in late January was revelatory at many levels. After careful attention to detailed parts of the EQ profile we had started from, he also helped with speaker placement and a few other considerations, all changes happening for the better. Secondly, I had the opportunity to learn more about Zu, Sean and his partners and their overall mission. He is clearly the kind of guy that we could use lots more of in audio. His sensible nature, diversity of experience, approachability and sincerity all contributed to a short but fascinating visit. I think after this experience, I find much to admire in the Zu team and that any owner of their products can rest easy knowing that solid people design, manufacture and stand behind this gear. The Rane EQ is very central, by the way, to obtaining appropriate matching to your room and system. After the Zu guys complete and distribute their bass set-up guide, this process should be very manageable for all but the most technically limited.

The grin factor
Having now listened to the Def Pros for a good amount of time, I can report that the sound in my room has attained new heights of performance and pleasure production. The quest to replace my beloved Nestorovic System 12 speakers has been a complex adventure, however, the learning curve was very much worth enduring. While several different speakers, electronics, wiring and room configurations were attempted, some provided occasional new insights, others left too much to be desired. So why is this present collection of gear able to do more of what I want than others? Let's take a digression if you don't mind.

The story really starts many decades ago. As a teenager I had the good fortune of visiting the pinnacle of audio goodness in the form of Radio Row aka Cortlandt Street in lower Manhattan, NYC. After the shock of seeing such glorious and exotic equipment including Marantz and McIntosh tube gear, Thorens and Garrard turntables and a bewildering array of fancy speakers, I came away realizing that high quality sound and music reproduction were seductive.

It was also in the realm of unobtainium regarding my less than modest wallet but I was eager to know, learn and savor. Fortunately, many of the sales guys in those shops were not only informed and friendly but
had high tolerance for pups like me, who mostly came there to be awed and maybe do some window shopping. Sadly that kind of atmosphere has all but disappeared these days. I became inspired to get a part time job so that enough dollars could be accumulated to get me on the path of sonic bliss. I won't drag this on forever, so bear with me... it is bringing back so many great memories as I write about this now that I feel compelled to leave the keyboard and go hear some of my oldies-but-goodies music collection. Whew, that session with Jefferson Airplane, The Band, Leonard Bernstein, E. Power Biggs and Judy Collins was just what I needed.

From those early days, I vividly recall the big impact listening to folded corner horn loudspeakers had on me. JBL was a highly revered company at that point and one shop had the famous Hartsfield horns on demo. I still am at a loss for words in trying to explain how gratifying that music experience was. Later with Altec Lansings, Klipschhorns and a few other similar beasts, it seemed that my inner core was being spoken to in ways that most speakers did not. Yes, KLH 9 Electrostatics could do certain things really well as could some of the acoustic suspension designs but for me, the big horn systems made magic happen. Clearly my budget was nowhere near the entry level for that kind of gear so I began with AR2a speakers and Dynakit electronics. It was a good way to get started and provided lots of enjoyment. That lead to Janzen bookshelf speakers and a big Fisher X-1000 integrated amp, with the Weathers turntable system. Yowza! Eventually, after much time, money and learning I actually discovered a fine high-end audio shop in Westfield, NJ, which was not far from home. Stuart's Audio was run by terrific people who carried excellent product lines and offered very attentive personalized care to its customers. In addition to finding new things to buy there, I became enough of a friend of the store as to be offered a part time job there in sales during the holiday periods while I was in graduate school. Abe Lincoln was one of my first customers and he had great ears - just kidding.

This shop was famous for custom installations and a first rate service department. That mattered a great deal to many and to me. Having JBL, McIntosh, Marantz, Revox and a long list of highly desirable products made just about every visit there equivalent to being at a continuing education seminar. Stuart's Audio held a special place in the lore of east coast stereo shops for a good while for many reasons, least of which was that they had not one but two JBL Paragons in use. Since this is ancient history, let me just note that the Paragon was one very large, long, modern looking speaker enclosure which housed both left and right channel speakers in the same package. It also cost a fortune but could do wonders with the right kind of accompanying gear and music. It was rumored that Frank Sinatra actually had two Paragons in his listening room too, one entire Paragon for each channel. Oy! I do think the Hartsfield corner horns did have more going for them but many happy hours were spent in front of those JBL beauties hearing fantastic renditions of classic rock faves.

I am bringing all this up primarily to indicate that in the early 1970s, I did purchase a pair of JBL Sovereign S7R speakers, not corner horns but big compression drivers and dual 15" woofers. They were used in two different rooms over time with varied electronics. Unfortunately, they never really had the chance to shine, primarily because I did not realize that they needed particular electronics to sound terrific. It was possible to get exciting reproduction out of them, but finesse would not be among the characteristics I managed to extract. I still miss those puppies, however. What this all means is that somehow in my sonic memories, the idea of good horn or horn-type speakers holds a special place. Having heard many of the modern versions of such systems has helped me to clarify certain goals and expectations - and this ultimately led me to the Zu Definitions.

The cool thing about the Def Pros is that they can do the best of horn things without any of the negative stuff that can often be carried along with those designs. Firstly, these Zu speakers are not enormous and don't overwhelm the room. Secondly, they don't show the hornesque/honky colorations people have often worried about. Thirdly, they produce deep, clean, satisfying bass. I will get to more of the goodnesses shortly. This digression can stop here.

The current situation
Here are a few of the descriptors that stand out for me in describing the sound now flowing in
my room. Dynamic, energetic, clean, fast, tonally balanced, integrated, convincing and engaging. I know these terms get tossed around a lot but they do fit this situation. It is surprising how the desire for big horns has diminished for me as of late. The immediacy and jump factor have never been better in my listening room.