Wilson WATT loudspeaker Page 2

Crossing over at approximately 2kHz, the HF driver is a well-established 1" dome from the French Focal company. Two points are of interest here: This cloth dome has a hard-cured impregnation and performs as a piston to quite high frequencies, in contrast to the early breakup behavior of the soft-dome tweeters almost universally used by other manufacturers. (Generally speaking, these are operating in well-damped resonant modes from 4kHz upward.) A hard-cloth dome resonance, however, may lie in the 15–25kHz range, though potentially it could still be audible (see the test results for the 19kHz peak). The concave form is also worth mentioning. The edge leads without break to a flat polyurethane foam suspension. A concave dome can offer a dispersion approaching that of a piston disc, with a more uniform off-axis pattern compared with that produced by the usual convex form.

The crossover uses the finest polypropylene capacitors and imported oxygen-free copper, air-core inductors, selected to 0.5% accuracy. The crossover is potted into an aluminum shell to form a rigid, vibration-free structure shielded from external electromagnetic fields such as those from the drivers or the internal wiring. The latter is Monster Cable's time-corrected, special-grade hookup.

Resembling a truncated pyramid, the enclosure has a largely asymmetric anti-parallel interior which minimizes internal standing waves; whatever remain of the latter are absorbed by an anechoic-grade foam lining plus a volume fill of polyester fiber wadding. Externally, both the WATTs and the 2Pi panels are fitted with low-diffraction, open-reticulated, polyester-foam grilles.

Factors responsible for the very low panel readout include the small area of the panels themselves, their high mass and stiffness, the internal seam bracing, and the linked cross-bracing from front to rear (between the drivers) as well as front to side. Add in the high-loss bituminous cladding lining the walls, the effect of the consolidated, well-secured crossover mass, and the contribution of several strategically placed, heavy slabs of ¾"-thick lead alloy securely bolted on. Last but by no means least is the panel material itself, which comprises a very hard, rigid, and relatively well-damped mineral-loaded polymer. The loading is said to be ceramic and mineral, and the panels can be sawn and milled like marble. In fact, it weighs almost too much!

The result is an exceptionally heavy, acoustically dead structure, providing a perfect, unyielding inertial mass against which the chosen drive-units can perform to their limit.

Sound Quality
This is a striking loudspeaker system, but first impressions appeared to be contradictory. How could such a thin-sounding speaker with almost no bass sound so good? It made a valiant attempt to blow away my disbelief and convince me that I was wrong and it was right. The WATTs, fitted with their 2Pi panels, did come close, but in the end I did not succumb.

Those things it does well it does very well indeed, so that you can hardly bear to drag your mind back to a reasonably balanced appreciation of its performance. Once you manage this, however, significant weaknesses become apparent. The upper midrange, and to a lesser extent the treble, are forward and projected. Interestingly, this did not detract too greatly from the impression of the stereo depth but it did leave the sound quite deficient in lower-mid foundation. As a consequence, cellos tended to sound like violas, while lower-mid and upper-bass sounds were emasculated. A further weakness concerned the bass, which did not recover from the depressed lower-mid level, leaving the speaker very subdued in the bass. Even kettledrum sounded thin and pinched; complex, harmonic-rich, low-frequency instruments appeared miniaturized. This was a serious flaw considering the price of the system, and was not greatly improved by the additional hanging baffle, in my opinion.

Depending on the amplifier used, there was also a touch of hardness on, or edge in, the upper midrange which was ameliorated by using the Goldmund Mimesis 3 power amplifier and one or two of the other high-current amplifier types such as the Krell. This mid-treble problem was rather amplifier-dependent (due to the impedance characteristic, perhaps?).

These matters aside, the WATTs displayed astonishingly low levels of perceived coloration over the 100Hz to 15kHz range. Cabinet or box coloration seemed to be nonexistent, and it was very hard to believe such clarity could be obtained from a pulp-cone bass-midrange unit. One can make some correlation between good detail and transparency and a "forward" balance, but the WATT went far beyond this association. It breathed detail and read subtle harmonic shading to such a high degree that complex material was unraveled, allowing an amazingly clear exposition of individual instrumental lines.

Perhaps only personal knowledge of the bass mid-driver allowed me to identify some slight "cone cry" coloration and a trace of congestion in the lower midrange. Aside from the occasional lower-treble glare, I really liked the treble for its speed and detail, and was barely aware of some breathy "zing" high in the range, close to inaudibility.


The bass was too light, but what there was proved to be articulate and tuneful and noticeably even. Fast bass transients were very well portrayed, if lacking in fundamental power. Given the lack of weight, the WATT did provide excellent rendition of dynamics. The ebb and flow of orchestral scoring was nicely captured, the speaker always sounding agile, fast, and "open."

The degree of focus was so high that this speaker imposed a most critical location on the listener. It was only too easy to find that perfect equidistant location where the soundstage focus "locked"—there was only room for one head at this position, however! Fortunately, substantially good focus was obtained over a wider-than-usual listening area. Stage width was excellent, reaching beyond left/right boundaries as defined by the speaker positions, while the superb transparency allowed the mind to reach well beyond the plane of the speakers to perceive considerable depth in appropriate recordings.

Notwithstanding the rather forward, close-up presentation, the WATT showed no difficulty in delineating the more subtle depth-perspective layerings of large orchestral recordings.

My initial reactions to the WATT, based on the Chicago '87 CES, described a dark block of transparent glass, possessing considerable depth, but on listening to the WATTs at home, I was reminded of the image of a reflection in a convex mirror: somehow smaller, brighter, and sharper, yet still showing good depth perspectives.

The clarity and transparency were continuing delights, but ultimately I failed to come to terms with the lack of bass and the thin, light midrange. Adding a subwoofer will slow the speedy bass, and cannot cure the midrange tonality imbalance. However, the added low-frequency weight will improve the overall performance.

Experiments with a Cello Audio Palette showed that it was possible to "flatten" the WATT in free space by programming the appropriate levels of boost in the low mid and bass range—typically +4 to +6dB, according to speaker and subject positions. Given the inevitable small losses in the Palette, the WATT could then sound well balanced without too great a loss in impact, life, or transparency, though the resulting system would not be able to play as loud. Such exercises are, however, self-defeating, and for review purposes, one has to take the product as it comes.

As I once said in a review of an early Decca cartridge, this product presents a view of Heaven and a glimpse of Hell. Hand on heart, I cannot give the WATT a straight recommendation. In major areas, this system produced the finest performance I have yet heard, despite or perhaps because of the simplicity of its driver engineering. Such a performance demands a hearing; for most, its superb resolution of detail, transparency, focus, and depth will all come as a revelation. One cannot realistically put a price on these aspects. It may well be love at first hearing, and you might sign a check on the spot.

However, if this is the heavenly aspect, then what about this speaker's darker side? Here there are several aspects to consider, all significant. To begin with, we have the most obvious feature, namely the light tonal balance and distinctly depressed bass—and not just the low bass either. Secondly, there is the erratic performance in varying vertical axes, together with the possibility of an audible high-treble peak for younger, more acute listeners (I have good sensitivity only to 17kHz). Last and by no means least, there is the matter of that awkward load impedance, and the corresponding, almost unforgivable dip to 0.33 ohms noted on the review pair.

At the beginning of this report I mentioned loudspeaker landmarks. Despite the negative aspect of the WATT's results, I do consider it to represent just such a speaker. For me, it is the most perfect exposition of cabinet construction, representing a very real proof of the adverse influence the cabinet exerts on so many speakers in current production. The drivers mounted in the WATT reproduce sound to quite an unsuspected quality level, specifically due to the cabinet's thoroughgoing acoustical engineering. I hope that this lesson will prove instructive to the rest of the industry; for the present, the WATT amply demonstrates just how superb its enclosure actually is.

It is easy to be wise after the event, but I cannot resist making the following comments. Considering its domestic free-field use: if the mid were equalized and leveled off at the 86dB level and the treble set to match; if the 2.5kHz dip were solved and the impedance notch corrected—then what kind of speaker would we have? Its obvious potential, married to a normal tonal balance, might result in a loudspeaker which would sweep all before it.

As the WATTs stand, however, my findings cannot be balanced objectively to provide a clear conclusion. My conscience is clear—I have provided the facts. From now on, dear reader, you will have to make your own decision.

Wilson Audio Specialties
2233 Mountain Vista Lane
Provo, UT 84606
(801) 377-2233

Bogolu Haranath's picture

With a minimum impedance load of 0.33 Ohms, we need an amp like the Relentless to drive them :-) .......

Ortofan's picture

... could have afforded the B&W 801 Matrix Series 2, the Infinity IRS Delta, the KEF R107, the Magnapan Tympani IVa or the Martin-Logan Monolith.






Bogolu Haranath's picture

You are gonna receive thousands of 'hate-mail' from Wilson customers :-) .......

Michael Fremer's picture

Why hate mail? Because Wilson's first speaker produced not such great measurements? That's silly.

volvic's picture

At the time I was blown away by the Concept 90 made by B&W. I heard so many other speakers at the time including the more expensive B&W's and Elipsons, but the Concept 90's where the ones I always wanted. I've been looking for a pair lately but most are pretty battered.

Ortofan's picture

... were you "blown away" - the CM1 mini-monitor alone, or the CM1 plus the CM2 sub-bass module?

Frank Van Alstine raved about the Concept 90 speakers when they were introduced in 1987.
You can read his comments by downloading his newsletters here:

volvic's picture

The complete package. Played an MSO record on an Oracle table with an Ortofon MC cartridge. Do not remember the electronics, maybe Bryston. It was magnificent, and if I could find a nice pair in like-new condition, I would retire my Kans to a secondary system. I just loved those speakers sonically and esthetically.

Bogolu Haranath's picture

Hi fi shark has some B&W Concept 90s for sale :-) .........

AJ's picture

Reading this review including physical reality measurements, it's clear Mr Colloms is truly a kind gentleman. Hope he's safe and well.

Soundfield Audio

John Atkinson's picture
AJ wrote:
Reading this review including physical reality measurements, it's clear Mr Colloms is truly a kind gentleman. Hope he's safe and well.

I stay in touch with Martin on Facebook and he's doing okay, AJ. Thanks for asking.

John Atkinson
Technical Editor, Stereophile

Michael Fremer's picture

Martin is and was honest. I don't read where kindness was involved.

AJ's picture

Good to hear. Take care too John, happy Easter, hope all are staying safe and staying in, listening to music.

Michael Fremer's picture

When I interviewed recording engineer Roy Halee (Simon and Garfunkel, The Byrds, Dylan etc.) back in the late 1980's he took me into his listening room where he had two systems set up. One was essentially Harry Pearson's system: Infinity IRS speakers, Jadis electronics and i think the same Goldmund turntable HP had. The other system in the room consisted of a pair of these WATT speakers and Mark Levinson electronics. Halee remarked looking at the WATT system "When I want to hear what's in the recording I use this, when I want to enjoy listening to music for pleasure i listen to those (the IRS system). Halee's recordings tell me there's no point arguing with him. Halee moved on to big Wilsons and stuck wilth various upgrades until a few years ago when he switched to Vandersteen 7s....which is what he now uses with Audio Research electronics and a Basis turntable. Yes, Roy prefers vinyl, but then what does he know? He should talk to some recording engineers..oh right! He is a legendary one!