Wilson Audio Specialties WITT loudspeaker Martin Colloms January 1998
Just two years after being reviewed by Thomas J. Norton and me in the January 1996 Stereophile (Vol.19 No.1), Wilson's WITT loudspeaker has been improved to Series II status. Though often in such cases the changes are minor, occasionally more radical revision are needed. In the case of the WITT, unforeseen problems in the paint finish when exposed to high humidity and large swings in temperature forced designer David Wilson to undertake a costly rethinking of how the speaker should be built and finished.
The design brief for the original WITT was for it to be a large, high-power, integrated one-box loudspeaker systema simplified approach to the WATT/Puppy system at roughly half the price. A key factor to reaching the aimed-for price point was the WITT's enclosure design, which featured phenolic plates, and MDF panels covered in a single black coat. Savings could be made here, while the visible full-gloss sides could be applied as separate finished pieces.
The approach sounded good on paper, but in practice it was another matter altogether. The severe temperature cycling and changes in relative humidity in the Asia-Pacific market resulted in differential expansion of the laminated panel edges and failure of the exposed paint. I owned a pair of Series I's for two years and had no problems here in London; I suspect that the high elevation and generally dry climate of Utah, the home of Wilson Audio Specialties, also produced no ill effects. But Wilson had to recall and repair many pairs of speakers at their own cost.
The company's only choice was to abandon the simplified paint system and subject the WITT to the full-sealing multicoat lacquer process of their more costly speakers. Because this inevitably increased the WITT's price (from $8888/pair to $11,890/pair), David Wilson also embarked on a design revision to improve the speaker's acoustic performance to match the new price, and also to introduce certain other improvements.
The acoustic damping within the enclosure has been optimized. The original detachable side panels are now factory-bonded to the enclosure, increasing the structural integrity and reducing sidewall coloration. The 12.5" bass driver is a new version with a stronger basket casting and slightly higher sensitivity. Less attenuation is included in the midrange feed to match the new woofer, and the tweeter level has also been revised.
The WITT is now built with a removable hatch in its phenolic base to give access to the cable bay on the fully potted crossover. A number of Caddock metal-film power resistors are wired across terminal posts, and also act as fast fuses in the case of a major overload. They have been selected for good dynamic performance on music, yet are still effective as fuses. Their replacement in the Series I required significant disassembly of the loudspeaker; a new cover plate allows for reasonably quick access and replacement. (This service design element has also been adopted for the X-1 Grand SLAMM Series II.)
The new full lacquer finish allows the customer his or her choice of color in place of the original's black. When it was suggested that I consider evaluating a Series II, I chose a "BMW" titanium metallic paint. When the speakers arrived, their finish could only be described as superb, on a par with that of Wilson's X-1 Grand SLAMM; the final result is substantially more appealing that the original.
In addition to the finish, the Series II WITT's appearance has been otherwise transformed since it made its debut at HI-FI '97 in San Francisco last May. The speaker's proportions now echo elements of Art Deco architectural design, and fit well in my listening room.
Although Wilson Audio will accept for remanufacture Series I WITTs shipped to their Utah headquarters, owners of original WITTs should consider the matter carefully before rushing in. The price slot previously occupied by the WITT has now been vacated. If your speakers have finish problems, you're covered by the warranty; however, if you chose the speakers appropriately in the first place, according to your available resources, then there's no reason to upgrade to Series IIs unless your budget permits and you're so inclined.
The WITT is a full-size, three-way, floorstanding loudspeaker coupled to the floor with steel spikes (standard) or heavy-duty spiked alloy PAWs (available at extra cost). I used the PAWs. The WITT stands 43" high, weighs 200 lbs each, and is bigger than a WATT standing on a Puppy.
No chances have been taken with the bass performance: a 12.5"-high power woofer from Focal is bass-reflexed by a good-sized rectangular ducted port. The cabinet tapers distinctively toward the upper section, producing a narrower, partly triangular shape that reduces the effects of cabinet-edge diffraction. This upper section houses the 6.5" SEAS pulp-cone midrange unit, and above that the high-sensitivity Focal tweetera 1" inverted titanium dome reinforced by a "dioxid" treatment (equivalent to anodization). The acoustically perfect if notably utilitarian grilles are made from open-cell porous polyester foam sheets, and look fine from a distance. Input connection is spade termination only, via a single pair of plain gold-plated binding posts.
Wilson claims a frequency response of 28Hz72kHz ±1.5dB; the rated impedance is 8 ohms; the sensitivity 90dB/W/m; and power handling is estimated at 200W of unclipped program from my original tests. In-room, A-weighted sound pressure levels of 105dB should be possible from a stereo pair in a typical room; ie, a high dynamic range. Good amplifiers as small as 50W are possible if they clip well, and where no more than naturally high sound levels are anticipated.
Listening: Like the Series I WITT, the II needed considerable running-in, even though some basic conditioning is done as part of standard production back at the Wilson factory. But the mists began to clear in the second week of use.
For this assessment I put together much of the original review system, including the Conrad-Johnson Premier Eight A and Premier Fourteen combination, the Krell KPS-20i/l and KSA-200S, plus Audio Research's LS22 and VT150SE. I also had the benefit of Krell's FPB 300 and FPB 600, their KRC-3 preamplifier, C-J's ART, and the Cary 805c monoblocks. LP sounds were provided by my usual Linn LP12/Lingo/Naim ARO/Koetsu RS2 combo feeding a C-J Premier Fifteen. Cables were by Siltech, van den Hul, and Kimber.
For a fortunate week I had a pair each of the Series Is and IIs, and was able to A/B them casually before fully installing the IIs. Though Wilson Audio had suggested that the new model was perhaps a dB or so more sensitive, direct comparison showed no significant difference. If anything, the I was a tad brighter in the high treble.
As supplied, the Series II was voiced somewhat richer in the treble than we've come to expect from Wilson, but this was quickly corrected by a factory-approved change in the appropriate fusible resistors. Such subtle voicing shifts are easily accommodated via that resistor/attenuator array below the crossover hatch. With guidance from Wilson, it might even be possible to obtain advice on fine-tuning the mid and treble levels for very different room acoustics.
My original pair of WITTs is a firm favoritethe II sounded sufficiently different to require a most careful examination. However, I'm happy to report that the changes have been for the better!
The Series II sounded more full-bodied than the I; the low mida region where the original was already no slouchwas now better structured and detailed. There was a touch more upper-bass weight, expressed with a crisper punch. On balance there was a bit less low bass, but you'd have to hear the models side-by-side to be sure of this.
The Series I's mid was mildly reticentlaid-back but still effective. Conversely, the treble sounded equally mildly "forward" and airy: sparkling, but not quite as well integrated as it could have been. The Series II illustrated this by bringing the mid fully into focus, without false shout or hardness in its upper range. This helped the transition to the treblenow more seamless, more delicately presented, with purer sibilants, and less of that hint of tinsel in the uppermost extreme of the treble often associated with the Focal drive-unit.
I had always felt that the overall blending of the WITT's drive-unit outputs was praiseworthy. Well, even more points were due the Series II. Overall, the midrange sounded richer, more natural, with small gains in detail and transparency. That mid quality was particularly apparent on voice; complex scores were highly resolved, the many voices remaining harmoniously balanced.
Though on first hearing it sounded slightly more dull and slow in tempo than the I, the II's greater detail and depth, allied to its crisper bass lines, soon restored my overall impression of fine rhythm and dynamics. While both models handled rock and jazz very well, the II was even more capable on classical music: kinder to rougher sources, more forgiving of distortion, and allowing playback at higher levels before the sound became unduly oppressive. And the IIs' stereo image showed an improved feeling of perspective, as well as increased stability of depth layering. Focus was also improved.
Those were the differences. What about the overall quality? Did the WITT II stand up at the new price?
Here is a large three-way speaker of authoritative dynamic range and power handling. Low-frequency extension approached but didn't match good subwoofer extension. However, it did match some of the best competing full-range speakers in terms of power capacity, detail, and speed. The WITT II had a nicely weighted balance that, without making it sound too slow, gave it a sense of poise and substance that never shortchanged a big orchestra. Though it reproduced all types of recordings without favor, its strengths were fully apparent on well-focused, transparent, and dynamic material.
In its II iteration the WITT remains, for me, an excellent speaker with slightly restricted low bass. Its looks and finish now equal its Class A sonic performance. I think the value standard remains correct at the WITT's new, higher price.Martin Colloms