When I interviewed recording engineer Roy Halee (Simon and Garfunkel, The Byrds, The Lovin' Spoonful, etc.) at his home in Connecticut back in 1991, he pointed to his pair of monolithic Infinity IRS loudspeakers and said, "When I want to listen for pleasure, I listen to those." He then pointed to a pair of early-edition Wilson Audio Specialties WATT/Puppys in a second system set up in the corner of his large listening room. "When I want to hear what's on a recording I've made, I listen to those." It was obvious: Halee respected the Wilsons, but he loved the Infinitys. Not surprising, since Dave Wilson designed the WATT section to be a highly accurate portable monitor, and monitors are designed for respect, not love.

A few years later, I attended a session at Sony Studios at which audio journalists listened to a live mike feed of a jazz trio through a pair of WATT/Puppys. At the turn of a switch, we could hear the same feed converted to 16-bit/44.1kHz digital, 16/44.1 processed with 20-bit Super Bit Mapping (SBM), 24/96, and 1-bit/2.83MHz via a prototype DSD (SACD) converter. We were told that the Wilson speakers had been chosen for their revealing nature. They revealed to many of us that the DSD conversion sounded closest to the mike feed, while to others—the real "experts"—it all sounded the same.

Wilson's website claims that the WATT/Puppy is the best-selling over-$10,000 loudspeaker in history. I have no way of verifying that claim, nor can I figure out how Wilson can make it—privately held companies are under no obligation to reveal sales figures. But any speaker that's been in constant production in one iteration or another for more than 17 years, as the WATT/Puppy has, must have impressive stats, "best-selling" or otherwise. Somebody besides recording engineers must love them.

Self-setup not recommended
Instead of waiting for recording engineer and Wilson marketing VP Peter McGrath to arrive, I set up the WATT/Puppy 7s myself, following the well-written and easy-to-understand instructions. While moving the speakers to the usual locations in my room (confirmed with spooky accuracy by RPG's speaker-placement software), I was immediately struck by how small these heavy, two-piece, $22,400/pair speakers are. (Each WATT weighs 65 lbs, each Puppy 105 lbs.) Usually, speakers look bigger when they go from the show or showroom floor to my listening room; in this case, they actually looked smaller. Not quite 4' tall, about 1' wide, and 19" deep, the oft-imitated WATT/Puppy is friendly to small rooms. Yet, at audio shows, they've easily filled big rooms with sound.

If you're relatively new to this hobby, you may have seen a number of speakers that look like the WATT/Puppy—both in shape and driver configuration. Many companies market speakers with flattened pyramidal tops and dual-woofered rectangular bottoms, while others offer standalone speakers that look like just the top WATT section. But rest assured—to my knowledge, no speaker had this look before the WATT. The WATT/Puppy is the original. All of the others—among them the Joseph Audio Pearl and the Genesis V—are, to one degree or another, imitators.

Wilson's excellent setup guide includes specific vertical angling requirements for the WATT, based on the height and distance from the speaker of the listener's ears. Wilson provides four sets of rear spikes for the Puppy so that you can adjust the system's height to ensure that the WATT's tweeter and midrange driver are at the correct height relative to your ears. Guesswork is eliminated: Plug in the numbers, and Wilson tells you which set of spikes to use. Before packing them up, John Atkinson measured the distance between the speakers and my listening chair and the height of my ear canal from the floor, so he could duplicate them in his measurements. While time coherence is claimed for the WATT/Puppy 7, phase coherence is not. (Wilson says that no speaker passes a squarewave unchanged.)

When you spend $22,000 on a pair of speakers, you're entitled to professional setup. All Wilson Audio dealers are trained in this service, which they're required to provide when you buy a pair of Wilson speakers. But after Peter McGrath had futzed around for a few hours, the speakers had been moved barely 2" from where I'd plopped them down originally. Still, their bottom-end performance had improved dramatically, and that affected the entire presentation.

$22,400 for WATT?
The gleaming WATT/Puppy 7s are finished in automotive paint. But even after I'd examined them at leisure in my own home, I wondered what could possibly make them cost $22,000/pair, even taking into account the usual audiophile manufacturing markup. I asked Dave Wilson about it.

Wilson told me that M transmits about 10dB less noise when excited than methacrylic, resulting in far less "group delay jitter" than the previous cabinet. The new material's hardness better matches the flanges of the drive-units, resulting in better energy transfer and quicker "settling" in the midrange. Wilson claims this new level of "quiet" allows one to hear deeper into the musical mix than before.

The Puppy cabinet is a combination of M and X material, the latter a high-density mineral and phenolic resin said to be as hard as steel and twice as hard as M, yet with outstanding damping characteristics. X is used for the front baffle and the cabinet's top and bottom. Wilson claims the material is extremely difficult to mill. Milling X takes about 12 times as long as milling MDF, and time is money; and because X is such an excellent insulator, it sends heat back to the milling tool instead of absorbing it, thus destroying the tool far more quickly than other materials.

Overall, Wilson told me, making the cabinets of M and X costs 15 times more than MDF. But, he claims, the result is improved transient performance, transparency, and speed, and far better low-level resolution. The 1" Focal titanium-foil, inverted-dome tweeter and 7" ScanSpeak midrange driver used in the WATT 6, both built to Wilson's specs and further modified at the factory, have been carried over to the 7.

A new Wilson-spec'd, ScanSpeak-supplied 8" woofer with a rubber surround replaces the foam-surround Dynaudio drivers used in earlier Puppys. New cabinet materials and a new woofer allowed Wilson to retune the rear-ported Puppy enclosure for deeper, more uniform bass. Crossovers in both sections were reworked (125Hz from Puppy to WATT, "about" 2kHz from midrange to tweeter); Wilson said the revisions to the WATT's crossover were "extensive," though he provided no other details.

While the WATT 7 looks no different from the 6, there are subtle cosmetic differences that are claimed to result in a cleaner integration of the WATT and Puppy cabinets. Producing the translucent, mirror-like skin is a costly, time-consuming process that first requires extensive surface sanding, then spraying on a sealer coat, then applying a 0.015"-thick coat of a waterproofing gel that's also used on yachts. After polishing, an auto-grade base coat of paint is applied, then the final color coat, and finally a clear urethane sealer. There's no denying the superb level of fit'n'finish, but overall, despite its flashy finish and choice of meticulously applied colors, the WATT/Puppy still looks to me like a squat, businesslike, fairly homely loudspeaker.

By any standard, the WATT/Puppy 7 appears to be exquisitely built. However, I suspect that to truly appreciate its physical and mechanical integrity, I'd have to watch it being built from the ground up, which I haven't. Another way would be to listen to it in my own home, which I have.

Just what I need: another Puppy in the house
Despite its small size, the WATT/Puppy 7 went very deep—down to around the mid-20Hz range in my room. The bass was impressively tuneful and relatively well-controlled, though it had a slightly loose and warm quality right up through to the midbass. The speaker's low-frequency performance had an attractively tactile quality without a hint of bloat, boom, or mechanical resonance. Both acoustic and electric bass were well-served, but some might prefer a more taut tuning that paid more attention to speed and solidity than to extension. The much larger Rockport Technologies Antares put out far less bass, but was tighter and somewhat better-defined.

The most obvious and consistent coloration I heard was in the transition from the lows to the midbass, where there seemed to be either a slight bump around what I'd guess is near 100Hz or a narrow trough between the midbass and lower midrange. Another contributor to the speaker's overall slightly warm sound could be the unusually large 7" midrange driver, which probably becomes directional, leading to a slightly suppressed reverberant field at its upper limits.

Because the WATT was initially designed to be a standalone speaker, a relatively large driver was necessary to get sufficient low-frequency response. Had Wilson designed a full-range speaker from the outset, it's unlikely he'd have chosen to use such a large driver to handle the 125Hz-2kHz range.

The WATT 7's other sticky sonic fingerprint (stickier for some than others) is the tweeter and/or how it's used. Focal's titanium-foil inverted dome has fans and detractors, and no matter how well you design a box or a crossover, the driver choice—in this case, a very detailed but allegedly "hot"-sounding tweeter that emphasizes the event over its aftermath—will affect the final outcome. I haven't paid attention to this tweeter's measurements in other applications, but I suspect one reason the small WATT/Puppy does so well in a large room is the tweeter's off-axis response. In smaller rooms, such as mine, the HF response can probably be somewhat sharp, but my space is both free of hard, reflective surfaces and carefully treated with RPG devices.

While I preferred the lighter, sweeter, airier HF performance of the Dynaudio Esotar tweeter used in the Rockport Antares and Merlin VSM Special Edition, I found the Focal's speed, transient clarity, resolution, and detail almost as enticing. I've been told that the Esotar can sound soft and rolled-off in larger rooms; there's a price to pay for every choice. In any case, the Focal did not sound so much bright as snappy, with a slight, smooth sheen on the very top.

The WATT/Puppy 7s produced an enormous sonic picture in my room, with the second most effortless presentation of depth and layered images that I've heard there. (First place goes to the Rockport Antares.) The WATT/Puppy convincingly placed reach-out-and-touch-'em images in space across the stage, well in front of the speakers, with greater delicacy and precision than any speaker I have reviewed—with the possible exception of the Rockports. They did likewise at the back of the stage, where their image clarity and transparency also rivaled the Antareses'. Overall image focus and solidity was in the Rockport class as well, which, before the WATT/Puppy 7, was a class of one in my reviewing experience. Also like the Rockport, the Wilson produced ultra-black backgrounds from which the most delicate and easily damaged sounds emerged unscathed.

Kuiet Kabinets are King
Though the Rockport Technologies Antares and Wilson WATT/Puppy 7 had completely different sonic signatures, my listening experiences of them were similar, most likely due to the fanatical attention both designers have paid to ridding the cabinets of resonances. While Rockport's Andy Payor went to almost heroic efforts, Wilson's achievement is also impressive, based on how the WATT/Puppys performed. I doubt the 7's cabinet-resonance measurements will be as impressive as the Antares', which were low to the point of being nonexistent, but I'd say the 7's cabinet was probably deader than most.

I found out what an essentially dead cabinet can do when the WATT/Puppies left and my reference Audio Physic Avanti IIIs returned. I had been playing a superbly recorded solo-piano CD, True Love Waits: Christopher O'Riley Plays Radiohead (Odyssey/Sony SK 87321), through the WATT/Puppys and marveling at the textural and tonal delicacy of the piano and its focus and clarity between the speakers. The keyboard's lower octaves were reproduced with the same percussive and harmonic clarity as the middle and upper octaves, with not a hint of clouding or congestion. I could almost feel O'Riley's fingers tapping the keys, and I bathed in the woody percussive afterglow as the felt hammers hit the strings. A velvety pitch-blackness behind the piano put the instrument in such dramatic relief that I could almost see its outline. This was the Antares Experience revisited: sound that was quick, almost ethereal, that melted in my ears and evaporated. That's what a speaker can sound like when its cabinet doesn't sing.

I'd heard True Love Waits only on the WATT/Puppy 7—the disc arrived after the speakers had already been installed. I gave one last listen just before JA arrived to take the Wilsons away to be measured; then, after reinstalling the Avanti IIIs, I listened again. The Audio Physic Avanti III ($12,000/pair) is an intelligently designed, well-engineered, sturdily built speaker with an ultra-sophisticated Hornflex cabinet. Overall, as expected, the Wilson outperformed the AP, though I'd bet the Avanti III's overall frequency response measured flatter.

The biggest difference I heard with the O'Riley disc was at the bottom end of the keyboard, where the 7's overall transparency easily bettered the III's rendering. While the piano's delicate tonal and textural characters and spatial presentation remained fixed through the 7s, the IIIs' presentation changed when O'Riley hit the lower notes. Transient and tonal clarity gave way to a slight cloudiness, congestion, and softness of intent, with a subtle loss of image focus and delicacy. The illusion of the piano centered between the speakers was, if not shattered, then somewhat disturbed. As with the Rockport Antares, the WATT/Puppy 7's freedom from congestion at all frequencies and at any volume level gave it an addictive ease and transparency that was like looking into a bottomless lake.

I fixated on Kenneth Wilkinson's superb recording of Vladimir Ashkenazy, Georg Solti, and the Chicago Symphony performing the five Beethoven piano concertos (Decca SXLG 6594-7, 4 LPs). Again, the 7's reproduction of the piano had a transcendent clarity, delicacy, transparency, and octave-to-octave consistency that the III, not surprisingly, couldn't match. Nor could the Avanti compete with the WATT's velvety, pitch-black backdrop. That's most of what you get for your extra $10,000: clarity, transparency, jet-black backgrounds, and a sense that, once the event has occurred, it drops off quickly into a black hole of nothingness without "singing" back.

Choices
About the time the WATT/Puppy 7s arrived, Halcro's Philip O'Hanlon asked if, just for kicks, I'd like to audition the dm10 preamp and a pair of dm68 monoblocks. Although adding more unknown variables would only complicate the review, I couldn't say no. So, during my two months with the Wilsons, I listened to: the revealing, almost painfully neutral Halcro combo; the Hovland HP-100 preamplifier driving the Halcro monoblocks; the Halcro preamp driving the Musical Fidelity Nu-Vista 300 power amp; and my reference combo of Hovland HP-100 and Nu-Vista 300. And for about a week, a Naim NAC 552 preamp was available as well.

Halcro wished that I would listen to the amps with Shunyata Research cables, including the Andromeda speaker cables ($2995), Aries interconnects, and a variety of power cords. I already had Shunyata's Hydra power-distribution system. Depending on your sonic perspective and your associated gear, these eye-candy cables are either sonically transparent, translucent, and pure, removing layers of baked-on grit and grain—or they modestly roll off the high-frequency response, soften leading edges, and cunningly suppress and sweeten upper-octave balance.

Whatever they do, I found myself flip-flopping the Shunyatas with a full set of Harmonic Technology Magic Woofer speaker cables and Magic interconnects, which produced a completely different sound on top: more edge, transient speed, and detail, sometimes with more satisfying bite, sometimes with unpleasant grit. With so many choices and variables swirling around my system (including, sometimes, essentially a whole different system), I'm not about to make sweeping pronouncements about how the Shunyata Research cables sounded. But with the WATT/Puppys, I preferred them overall to the Harmonic Technology cables, regardless of partnering electronics.

Listening to familiar music
Because the WATT/Puppy 7s' image delicacy and pitch-black backdrops were reminiscent of the Rockport Antareses', I played some of the music mentioned in my August 2002 review of the Rockport to see how it would compare. The WATT/Puppies delivered Classic Records' 45rpm pressing of Simon and Garfunkel's Bridge Over Troubled Water on a wide, deep, transparent soundstage on which, out of black backgrounds, layered images appeared—one image might be as delicate and ethereal as a bubble, even as the one right next to it was hard and etched. The gradations of texture and tone were reminiscent of the Antares Experience (and that's saying a bank account full), but not quite as vividly and delicately rendered.

The bass harmonica on "The Boxer" once again "thundered in like a freight train, each puff of the player's breath creating an airy, eerie three-dimensional eruption," as I said in my review, while the background voices on "The Only Living Boy in New York" hovered almost magically, elevated at the very back of the stage. The triangle and panpipe in this song, which usually seem to be flattened against the front of the Avanti IIIs' speaker baffles, floated in three-dimensional space well in front of the WATT/Puppys.

Although it was somewhat easier to get a handle on the WATT/Puppy's overall tonal character than on either the far more expensive Rockport Antares or the far less expensive Audio Physic Avanti III, the ability of such a compact design to produce all but the very lowest musical notes with such notable clarity and control, and deliver it on an expansive, transparent, and coherent three-dimensional picture, is an impressive accomplishment. It helps explain why the WATT/Puppy has stayed in production all these years. Add to that the speaker's ability to play loudly without strain, deliver unlimited dynamics at both ends of the scale and the fine gradations in between, and its believable harmonic accuracy, and you have a relatively small speaker that does almost everything you could want, with minimal compromise. With the WATT/Puppy, even a space-constrained audiophile can have it all—or at least most of it.

Conclusions
The Wilson Audio WATT/Puppy 7 is a speaker you can both respect and love with ease. It goes low, plays loud, responds quickly, and sounds delicate, detailed, and vivid. It is rhythmically lithe and dynamically expressive, and it projects an impressively large, dramatic, room-filling picture. After the $41,500/pair Rockport Antares, the $22,400/pair WATT/Puppy 7 is the most open, least congested speaker I've heard.

I've been told that the various WATT/Puppy iterations over the years have vacillated between soulless perfection and soulful compromise, stopping everywhere between. I can't speak about the WATT/Puppy 1, 2, 3, 4, 5, or 6, but I can about the latest edition: The 7 has both soul, and, I'll bet, superb technical performance. While its frequency response appears to have been altered from strict flatness to add layers of love in the midbass and high frequencies, the WATT/Puppy 7 has so may positive attributes and so few negative ones that I do not hesitate to say that it's one of the finest-sounding and -performing speakers I have had the pleasure to evaluate. It does just about everything you could want from a speaker of any size. Is it "perfect"? No. But it's surely good enough!

Description: Three-way, floorstanding, dynamic loudspeaker in two sections. Drive-units: 1" titanium-foil inverted-dome tweeter, 7" midrange cone, two 8" woofers. Crossovers: 125Hz, 2kHz (approximately). Frequency response: 21Hz-21kHz, +0/-3dB. Nominal impedance: 4 ohms. Sensitivity: 93dB/W/m.
Dimensions: 40.25" H by 12.25" W by 18.5" D. Weight: 170 lbs (WATT, 65 lbs; Puppy, 105 lbs).
Finishes: M material (WATT), M and X material (Puppy), finished in automotive paint; various colors available.
Serial numbers of units reviewed: WATT, 11173, 11174; Puppy, 11175, 11176.
Price: $22,400/pair. Approximate number of dealers: 41.
Manufacturer: Wilson Audio Specialties, 2233 Mountain Vista Lane, Provo, UT 84606. Tel: (801) 377-2233. Fax: (801) 377-2282. Web: http://www.wilsonaudio.com/

Analog source: Simon Yorke S7, Linn Sondek turntables; Immedia RPM-2, Graham 2.2, Linn Ekos tonearms; Lyra Titan, Transfiguration Temper W, Linn Akiva cartridges.
Digital source: Musical Fidelity Nu-Vista 3D CD player; dCS Verdi, Purcell, Elgar Plus SACD/upsampled CD player; Alesis Masterlink hard-disk/CD-R recorder.
Preamplification: Hovland HP-100, Naim NAC-552, Halcro dm10 preamplifiers; Manley Steelhead, Linn Linto phono preamplifiers.
Power amplifiers: Halcro dm68 monoblocks, Musical Fidelity Nu-Vista 300.Loudspeakers: Audio Physic Avanti III.
Cables: Phono: Hovland Music Groove, Graham IC-70. Interconnect (all balanced and unbalanced): Harmonic Technology Magic Link One, Pro-Silway III; Shunyata Research Aries, Aries-S. Speaker: Harmonic Technology Magic Woofer, Shunyata Research Andromeda. AC: JPS Labs Kaptovator, Aluminata; Wireworld Electra Series III; Shunyata Research Anaconda, Diamondback; Synergistic Research Designer's Reference.
Accessories: PS Audio Power Plant P300, Shunyata Research Hydra power-line conditioners; Sounds of Silence Vibraplane active isolation platform, Symposium Ultra shelf & Rollerblocks (Tungsten, Grade 3 superball), Finite Elemente equipment stands; Audiodharma Cable Cooker, Walker Precision Isolated Motor Drive; ASC Tube Traps, Shakti Stones & On-Lines, RPG BAD & Abffusor panels.—Michael Fremer

The Wilson Audio WATT/Puppy 7's sensitivity was above average, at an estimated 90.6dB(B)/2.83V/m, which is not significantly different from its predecessor, the System 5. However, also like its predecessor, it will need a good high-current amplifier before it can be driven to satisfying levels. Its impedance drops to 2.4 ohms at 78Hz and remains below 6 ohms for much of the region where music has its maximum energy (fig.1). In addition, an impedance of 4 ohms at 59Hz is associated with an electrical phase angle of -34 degrees, which will add to the drive difficulty. With both its enclosures ported, interpreting the impedance curve at low frequencies is difficult, but it appears that the Puppy's 3"-diameter port is tuned to 27Hz or so, while the WATT's 1" port is tuned to about 80Hz.

Fig.1 Wilson WATT/Puppy 7, electrical impedance (solid) and phase (dashed). (2 ohms/vertical div.)

Befitting its heroic construction, the Puppy's enclosure was extremely inert. A single mode was evident at 422Hz on its side (not shown), but this was so low in level that it should be inconsequential. The WATT had one clearly defined resonance visible on its sidewall at 266Hz (fig.2), with some other activity evident in the octave above that. As all this behavior is low in absolute terms, it should be subjectively benign.

Fig.2 Wilson WATT/Puppy 7, cumulative spectral-decay plot calculated from the output of an accelerometer fastened to the WATT cabinet's side panel. (MLS driving voltage to speaker, 7.55V; measurement bandwidth, 2kHz.)

As with earlier versions of this system, the WATT/Puppy 7's behavior at low frequencies is complex. The black trace in fig.3 shows the response of the WATT's midrange unit, measured in the nearfield with the speaker driven directly by the amplifier, without being routed via the Puppy. Its output extends to below 100Hz, but is not helped much by the WATT's port (green trace, plotted in the ratio of its radiating diameter to that of the drive-unit). The red trace is the output of the Puppy's woofers. They basically cover the octave between 50Hz and 100Hz, with what appears to be a second-order rolloff above that region. The Puppy's big port (blue trace) peaks as expected from the impedance plot between 20Hz and 40Hz, which is a little low in frequency to usefully extend the Puppy's output.

Fig.3 Wilson WATT/Puppy 7, nearfield responses of the WATT midrange unit (black) and port (green), and Puppy woofers (red) and port (blue).

As mentioned, I connected the WATT directly to the amplifier terminals to generate the black trace in fig.3; this curve is repeated as the blue trace in fig.4. However, when I repeated the measurement with the amplifier hooked up to the Puppy's input terminals and the WATT connected to the Puppy Tail, which emerges from the top of the Puppy, I got the red trace in fig.4. Either there is a series crossover element in the WATT feed or the Puppy woofers are actually connected in inverted acoustic polarity. If the latter, then what you see in this graph is partial cancellation of the WATT's nearfield output by the opposite-polarity Puppy output. I investigate this below, but it is fair to note that the WATT/Puppy 5 measured identically in this respect.

Fig.4 Wilson WATT/Puppy 7, nearfield responses of the WATT midrange unit connected directly to amplifier (blue) and via Puppy Tail (red).

Fig.5 splices the complex sum of the low-frequency responses shown in fig.3 (taking both acoustic phase and the different distances of the sources from a nominal farfield microphone position) to the response at 50" averaged across a 30 degree horizontal window on the tweeter axis. The middle of the midrange is indeed depressed—I used farfield power-spectrum measurements to check that this was the case—but the overall trend in the upper midrange and treble below 10kHz is fundamentally flat, with small peaks balanced by dips. (My sample appeared flatter in this respect than that measured at the Canadian NRC for the SoundStage review, which appeared to have a less sensitive tweeter.) Earlier versions of the WATT had a more prominent upper midrange than the 7. However, as MF suspected, the new speaker's octave between 10kHz and 20kHz is depressed compared with the 5, which delivered a full measure of treble energy between 10kHz and 16kHz.

Fig.5 Wilson WATT/Puppy 7, anechoic response on tweeter axis at 50", averaged across 30 degrees horizontal window and corrected for microphone response, with the complex sum of the nearfield responses plotted below 300Hz.

The WATT's midrange unit is a bit on the large side to maintain its dispersion through the crossover to the tweeter, the crossover point appearing to lie at just under 3kHz. This can be seen in fig.6, the speaker's horizontal dispersion plot. While the contour lines are uniform and evenly spaced to around 30 degrees to the WATT/Puppy's side—something that correlates with stable, accurate stereo imaging—the octave below 3kHz is depressed at extreme off-axis angles. All things being equal, this will tend to make the speaker sound not quite as "present" in a large room as it will in a small room. However, as this coincides with a small on-axis peak in the same region, the speaker may well sound correctly balanced through this critical range. Note that the Focal tweeter is very directional above 10kHz, which will make the WATT/Puppy 7 sound a little lacking in air in large rooms. By contrast, there is a lot more energy apparent to the speaker's sides above 20kHz, though this will be an issue only for small children and large dogs.

Fig.6 Wilson WATT/Puppy 7, lateral response family at 50", normalized to response on tweeter axis, from back to front: differences in response 90 degrees-5 degrees off-axis, reference response, differences in response 5 degrees-90 degrees off-axis.

In the vertical plane (fig.7), the WATT/Puppy's balance is maintained on or just above the tweeter axis to a much greater extent than earlier versions of the speaker. Below that axis the presence region loses energy—which, I assume, is one of the reasons Wilson provides spikes of different lengths to ensure that the listener sits on the optimal axis. Suckouts develop at the upper crossover frequency for axes much above or below the tweeter.

Fig.7 Wilson WATT/Puppy 7, vertical response family at 50", normalized to response on tweeter axis, from back to front: differences in response 15 degrees-5 degrees above axis, reference response, differences in response 5 degrees-15 degrees below axis.

The WATT's sloped-back baffle makes it appear as if it is a time-coherent design. However, the speaker's step response (fig.8) shows a more complex behavior. The slight negative-going spike at the start of the step is due to the WATT's midrange unit, which is connected in inverted acoustic polarity, but this spike is broken almost immediately by the sharp, positive-going spike of the tweeter. The negative-going overshoot of the tweeter's step overlays the midrange step, implying good frequency-domain integration. However, just after the 5ms mark, the once-again negative-going output of the WATT's midrange unit is interrupted by the positive-going output of the Puppy's woofers. Looking at the individual step responses of the drive-units (not shown) confirmed this diagnosis. The Watt and Puppy woofers will not sum correctly in an anechoic environment, though it is fair to point out that the situation will not be as simple in a room. Nevertheless, I note that Mikey did comment on a lack of energy in the lower mids.

Fig.8 Wilson WATT/Puppy 7, step response on tweeter axis at 50" (5ms time window, 30kHz bandwidth).

Finally, the WATT/Puppy 7's cumulative spectral-decay plot on the tweeter axis at 50" (fig.9) was not as clean as the best I have seen, nor was it as clean as that of the WATT/Puppy 5, at least below the older version's tweeter resonance, which lay at a low 15kHz. But the initial decay is very clean, which presumably explains why neither MF nor I, in my auditioning of the speaker in his room, was bothered by treble grain.

Fig.9 Wilson WATT/Puppy 7, cumulative spectral-decay plot at 50" (0.15ms risetime).

In some ways, the WATT/Puppy 7 offers enigmatic measured performance. The broad overlap of the midrange and bass units and their phasing mandate careful setup of the speaker so that it can take advantage of the room acoustics rather than fight them. But then, the things it does right will be readily audible.—John Atkinson