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Reviewer: David Abramson
Digital source: Rega Jupiter 2000, Lector CDP 0.6T
Integrated amplifiers: Unison Research Unico; Unison Research Unico SE parts conneXion Level 2 modified [on review]
Speakers: Totem Arro
Cables: Argent Audio Pursang interconnect; Home Depot 6-gauge speaker cable (construction as described in Bound for Sound magazine)
Equipment Stand: Sound Organization
Room Treatment: Eighth Nerve
Room size: 16.5' L x 14.5' W x 9' H
Review component retail: $3,490

Great (audio) minds think alike
One of the things I dearly love about our hobby? Its mysteries and profundities are such that it draws great minds from a whole host of other disciplines, military and civilian alike. Witness designers such as John Dunlavy, Paul Klipsch, John DeVore, Nelson Pass and more recently, Tranh Nguyen of Nuforce and Robert Grost of Cerious Technologies. These gents are not just standout audio designers, they are standout minds who have made the pilgrimage to audio because they feel strongly that they can build a better (sounding) mousetrap, all presumably in the service of music. It gives me pause just thinking about it. Imagine all the research and development by Jim Wang that went into the production of say, the Harmonic Tech Cyberlight interconnects; or Serguei Timachev's Stealth Indra just so you and I could get closer to the music. Look at nearly any of the truly classic audio products that have ever been. You can be certain there's an outstanding mind behind it.


It is for this reason that the notion of the modification in the interest of improving a particularly well-designed component such as any by the superb designers mentioned above has always rubbed me in the wrong direction, rhythmically. For much like the stockbroker who's supposedly wonderful at picking the right stocks but still needs to come in to work each day to feed his family, I have long felt that many of these improvers would not need to make a living improving upon other people's ideas if they truly were the brilliant component designers they think they are.


But then, the Unico SE Underwood HiFi Level 2 mod is no re-imagining of a stock Unico SE in an attempt to out-think its esteemed (and in my estimation brilliant) designer Professor Giovanni Sacchetti. Rather, this modification merely amounts to asking the hypothetical question: "What if there weren't any (well, too many) cost constraints during the parceling out of the parts on the designer's palette in the creation of a Unico SE?" This is an entirely reasonable question. It's one which is usually answered by taking a look at the next model or two up in any given line. Here another company is answering it. No repainting the Sistine Chapel or colorizing a Charlie Chaplin film, just take what is a basically phenomenal piece of design and loosen the purse strings considerably in its outfitting. According to Walter Liederman, "we don't modify any component we don't like. You can't take something that's no good and make it really good. But you can take a good product and extend the performance to world-class." That's exactly what the Underwood HiFi Level 2 Unico SE mod is all about.


Secondly, the guys doing the improving and parts selection are not some garage-based, high school shop-trained solder jocks. They are none other than Chris Johnson and Glenn Dollick, former head honchos at Sonic Frontiers and owners of one of the busiest DIY parts supply shops around. This résumé gives modification designer Johnson and executeur Dollick all the cred necessary to confidently step up to the plate and mull over what might or might not constitute an improvement in the context of an already expert, award-winning design like the Unico SE.


Who designs a mod is important - that's why Walter Liederman picked wisely. I give you the example of the well-known parts dealer/DIY speaker source in New York where I grew up. In order to feed my addiction, I would occasionally stop by to ogle the latest DIY projects he had on display in all their completed glory. The proprietor is an ornery sort with a sharp tongue. He used it then mainly to chop away at retail speakers from pretty much every well-known high-end designer. He'd say things like "look at the cabinets on my speakers vs. theirs. Mine are 3 inches thick, are theirs?" Or, "look at the cheap $8 woofer fancy pants uses in his speakers. My woofers from Cabasse/Accuton cost $200 each."


And so they did. And they were beautiful to look at. But nearly every time I got to actually hear one of 'his' designs utilizing these mind-numbingly expensive drivers, there was something fundamentally amiss. Unfailingly the finished product was either too bright or the imaging was unfocused; or the bass was loose and chuffy or more commonly, some combination of all the above. Amazingly, with all the several-hundred-dollar drivers and 3" thick cabinetry, none of these designs were capable of making a sonically coherent statement.


Thus, my friends and I went from feeling ripped-off by the big-name speaker designers to feeling that, maybe, there was a little something to this research and development by a great designer after all. And maybe, there was a bit more to speaker design than the price of your woofer. One simply cannot take a bunch of pricy drivers, stick them on a thick, non-resonant box, have a computer create a crossover and come up with a Totem Hawk or a Zu Druid. You can't do this with a DIY amplifier either. Or, for that matter, with an amplifier mod. That's why I met the sizable UPS box containing my hot-rodded Unico SE from Walter & Co. with high hopes and no small amount of trepidation.


Hot-rodding a hot-rod
I've owned the stock Unico for about two years, an eternity in audiophile years. I've come to feel strongly that this amp is about as good as you can do for below two grand. Punchy, fast and tonally a touch sweet, it's a killer of an integrated. That said, the Unico SE -- by many accounts including Sam Tellig's -- is an all-around step-up. And you want to mess with that kind of success? "Underwood HiFi's playing with fire" I thought. But was Walter burned? While the exterior simply says bigger Unico, the interior, as per Walter's list, has benefited accordingly over the stock piece:

  • Replace the stock preamp tubes with two premium mil-spec Mullard CV4003s (12AU7s). These are 10,000 hour ultra low noise tubes with ultra low microphonics
  • Two MultiCap PPFXS polypropylene film and tin-foil interstage coupling capacitors
  • Two 1uf Auricap metallized polypropylene preamp input coupling capacitors
  • 24 x Japanese Riken ½ and 1-watt signal path carbon resistors with gold-plated leads
  • 8 x Vishay-Telefunken SF4007 ultra-fast soft recovery diodes to rebuild 2 existing bridge rectifiers + 2 x IR Hexfred diodes
  • 6 x BlackGate power supply electrolytic capacitors
  • 2 x Burr-Brown OPA627 op amp-based PCB assemblies for amp driver stage
  • 2 feet of DH Labs "Revelation series" pure 99.999% silver solid core input signal wire with Teflon tape-wrap dielectric
  • 2 premium Vampire "direct gold-plated over copper body" RCA female input jacks
  • 4 x WBT 0763 single output speaker binding posts
  • 3 sheets of SoundCoat chassis damping material cut & applied where applicable
  • 4 EAR large Sorbothane isolation feet
  • TRT WonderSolder used throughout
  • 8 hours labor
Here's the thing. I've never heard the stock SE. For context, read our archived review of the Underwood HiFi Level 1 Unico mod against the Level 2 mod penned by our own Paul Candy aka Candyman. You'll find some thoughtful musings as to the sonic gains from throwing some coin at the undoubtedly fine Parts conneXion Level 1 mod of the standard Unico and having it upgraded to the Level 2.


Sonic Commentary
As compared with the stock Unico in standard guise, this modified (anointed?) beast is blessed with better bass; the broader, more defined soundstage that is the product of increased resolution; and -- most saliently improved to the point of startling -- dynamics and Naim-like pace and rhythm. The first word that came to mind after the requisite 200-or-so hour break-in was simply revelatory. By this term I mean it showed me in lurid detail exactly what every other component in my system sounded like in comparison to every thing else I had in-house. It did so in a patently obvious way though I never found the amp to be anything but sonically delightful despite this microscopy.


I changed speaker wires from the Ensemble Megaflux FSF to TG Audio's. Immediately, the sound was very obviously fuller in the low mids, with less detail, softer edges to instruments and voices and being a bit more laid back. I changed CD players from the Jupiter to the Lector. Immediately, string tone was more natural and the stage deeper. Simultaneously, singers and soloists were more present. I changed interconnects from my resident Argent Audio Pursang to some nameless el-cheapo and could tell exactly why and wherefore the Pursang walked all over it.


It's all about the extent to which a great amp with superb resolution lets you do this without ever sounding annoying or edgy. The next thing that jumped out at me was the dynamics. It was a Sunday and I had on the Deutsche Gramophone recording of Haydn's Great Mass in C, with Fricsay conducting via the Lector. I was making eggs in the kitchen. Haydn's "Te Deum" comes on, a short choral piece as kind of a desert after the main course of the Mass. I am immediately pulled out of the kitchen onto my couch and hunker down in the listening seat praying the eggs will hang on for just a sec. This piece proceeds to dazzle and draw me in. I have to pay attention. The chorus swells, the music soars. This is no stock Unico! The textures and the flow, it's simply beautiful. The eggs got a bit singed.


Rene Jacobs "La Nozze di Figaro" [Harmonia Mundi] then proceeded to show me why it's won all those awards. The soundstage was perfect, broad and deep and the business of the characters on stage -- the door knocks, foot shuffling and general interplay -- came through loud and clear as I hadn't heard it before. And the pacing! This amp is just superb in the PraT department even though we're talking opera here. I was tapping my feet to everything from "La Ci Darem La Mano" to "Deh vieni" and string quartets.


Death Cab For Cutie's Transatlantics was superb in this regard, as was the new girlfriend-requested U2/Beck fest consisting of the back-to-back playing of Achtung Baby! and Sea Changes. With all of these CDs, bass was slammin' as the kids say, voices were at times in-the-room present and dynamics, to be sure, were ridiculous. Ridiculous to the point where on several CDs, I actually had to lower the volume with the handy-dandy (but now plastic and no longer nice wooden) remote in order to keep my neighbors happy and me from being that guy in the Maxell audio tape ad.


Soprano voices like Renee Fleming's singing "Porgi Amor" swelled with new-found -- and winceless -- ease as the climax of a piece came. Warhorse symphonies like Dvorak's New World started off low and slow and then just pounded the hell out of the little Totem Arros when Telarc conductor Joel Levi asked for all the Atlanta symphony had to give.


Getting to review the modded Unico SE had made me a bit nervous. Since it was a Unico, I knew it'd be good. Since it was a Unico SE, I knew it would probably be better than my standard non-SE unit. And since it was an Underwood HiFi Level 2 Unico SE, I expected hell for my sanity. The worst thing that can happen to a reviewer is to be reviewing a superb piece and starting to feel you can't live without it while simultaneously knowing that even if you sold your listening couch, you'd never be able to afford it!


Were my fears well founded? Yes and no. The new Rene Jacobs conducted recording of Haydn's The Seasons on Harmonia Mundi is a magnificent example of what this hobby is about in every way. The music is simply uplifting and the recording sublime. Yes, there is a lot of vocalizing about "lush greenery" and "melting snows" and all the usual dramatization of the natural realm endemic to libretti of the day, though with these singers and this degree of tuneful inventiveness, this piece could be about the yellow pages or the tax code and I'd listen.


Over the stock standard Unico, it was enchanting, moving and uplifting. The tonality too, for me the sine qua non of the Unison Research gear I've heard. It was as on as ever with just a pinch of sugar. Hooking up the modded SE, your foot starts to tap a bit more to the jaunty "Schon eilet froh der Ackersmann" that Simon, played by baritone Dietrich Henschel, sings so lyrically. Likewise, track 9 is a beautiful part for full chorus praising the Lord, source of all the beauty of the seasons and each one's particular bounty. With the SE, the bass drum that underpins the choral entry was fuller and more of the mechanics behind the production of the sound -- the striking of damped wooden sticks on taut drum skin -- could be heard. And the stage was spread a bit wider. Happenings within that stage too were more clearly localizable.


But the stock Unico gave up relatively little in terms of allowing me to enjoy the piece as a whole. It didn't punch as hard and wasn't quite as toe-tapping but the fact that I can even draw close comparison with so upgraded a beast as the Level 2 SE speaks volumes for the solidity of the Unico's fundamental design. It could also have something to do with the fact that the Unico SE, by virtue of its larger power output, incorporates 4 Mosfets per side as opposed to the stocker's 2. You might make an argument that the stocker's somewhat simpler path to the speaker keeps it in the running in terms of its ability to portray, if not sheer scale and dynamic punch, at least intimacy and inflection.


As evidenced by its performance on my next two selections, that it does nearly as well if not as well as big brother. On smaller scale fare including Ian Bostridge's new "Die Schöne Müllerin" recording with accompanist Mitsuko Uchida on EMI and the Cowboy Junkies new CD Early 21st Century Blues on Latent Recordings, the stock Unico showed itself to be at times nearly the equal of the modded unit in its ability to present these works with immediacy and fluidity.


Yes, there was more separation and space between Uchida and Bostridge through the Level 2 SE and just plain more venue around them - but not vastly so. The same went for a clearer delineation of Uchida's runs and left-handed subtleties. So too with the Cowboy Junkies on "Brothers Under the Bridge". A banjo picked throughout the song could be more clearly heard through the mix when listening through the Level 2. And as mentioned before, the bass that underpins so many of the tracks on this CD was certainly more fulsome. But fortunately for both me and my thin wallet, the stocker made enough of the musical information that mattered on all three CDs come through to convey the overarching musical message loud and clear.


If I were reading rather than writing this review, here's the two questions that would be foremost in my mind: "How depressed were you to have to send the Level 2 back?" and "Will your life ever be the same again now that you can only listen to the stock-standard poor man's Unico?"


As good as I think the Level 2 SE is -- and it is a superb amplifier in every way -- I can get by. This is not so much a statement about the Level 2's quality as it is an affirmation of the solidity and right-mindedness of the original design. If I had a larger room, less efficient speakers or listened mostly to more bombastic fare, then I'd likely be showing more signs of withdrawal. As it stands, there's only a mild tremor and a bit of excessive sweatiness.


Speaking as a card-carrying Unico owner, to those of you with a Unico SE, let me say you've made a superb choice. As it stands, the Underwood HiFi Unico SE Level 2 is among the two or three best amplifiers I've ever heard. It certainly ranks as the best integrated amplifier I've ever heard. And I've heard plenty of those. Heartily and enviously recommended!
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