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The gestation of the Diva Monitor condenses into a telling anecdote. Hannes pushed for it, Martin insisted that the Diva floorstander was enough. Hannes disagreed but Martin refused to pursue the discussion. As co-owners of the company, both have to be on the same page to green-light projects, then sign off on 'em. The Diva Monitor seemed stillborn. But Hannes is resourceful. As a former cabinet maker, this would be child's play. He moonlighted a pair in secret, tested it to great personal satisfaction in his own studio and then snuck it to a trade show where the floorstanding Diva would be introduced. Except that once there, that particular room didn't cotton perfectly to the setup. Even its designer had to agree that the performance of the floorstanding Diva was most certainly adequate but not exactly mindblowing. So Hannes pulled out his stealth pair of Diva Monitors, the speaker/room combo gelled and the rest was history. Minds were blown, Martin was converted and this particular exhibit reportedly became the talk of the show.


Therein hide lessons. For a designer, it's greater fun to aim for the stars and push the envelope. A marketing guy meanwhile understands that his bread and butter sales will come from entry-level models. More people can afford those. Many shoppers of course instinctively sympathize with the designer. The popular law says, expensive is always better. As is bigger. Why bother with the small and cheap stuff? Surely it's pock-marked by compromise. What they want is the best. Which once again overlooks that the room may not be - the best. Nor uncompromised in size or acoustics for the purposes of their dream speakers. While on the subject of "best", WLM's trade secret hides behind the PAC acronym for phase acoustic corrected. Major companies have made offers to either OEM Martin Schützenauer's treble system or outright purchase the technology. WLM refused. They're not letting on what's hiding behind the PAC enclosure either.


Its shape suggests deliberately broad dispersion, its depth is greater than a conventionally loaded dynamic tweeter would necessitate. Ready to take a guess? UltraAudio's Jason Thorpe "...used a flashlight to obliquely investigate what's going on in there. Each enclosure seems to contain two cone drivers with an apparent diameter of about 1.75". Each tweeter seems to be recessed into a cylinder 1" to 2" deep. These two cylinders don't point straight ahead: one fires in toward the listener, the other outward, toward the sidewalls." No ribbon or air motion transformer then.

Add the fact that all WLM setups I've heard or seen pictures of never used toe-in. Armed with this information, one could come to certain conclusions. Wave-guided tweeters such as Jason described will produce controlled dispersion. This creates enhanced directivity and minimized lobing. Without toe-in, WLM's inner tweeters will be aimed directly at the listener, the outer tweeters at the side walls. Averaged -- i.e. considering typical setups in standard-size rooms and normal listener distances -- this will create direct and reflected HF information within a specific time window of arrival times or phase rotation. As we learned, the so-called Wave Control of the active-drive circuit can adjust phase rotation just for the tweeter by up to 45°. The rationale given is to improve PAC behavior in well-damped rooms, i.e. setups where the sidewalls will absorb or diffuse the outer tweeter action. Then consider the acronym. It doesn't say phase-correct. It says phase, acoustically corrected.


WLM contends that conventional treble systems don't allow our bio computer to maximally process spatial cues from the portrayed mix of high and low frequencies. As a result, our brain doesn't make total sense out of the data. It can't fully simulate the perception of completely believable holographic dimensionality. The sonic image is never entirely divorced from the speakers. Something about it remains artificial. WLM's proprietary PAC system claims to result in a more credible recreation of spatial cues. It "utilizes insights into phase equalization and human hearing to overcome the acoustical short circuiting of conventional left/right loudspeakers that modulate their HF response. "


It is well known that image specificity and dimensional realism in playback are a function of HF performance. Lower frequencies become more and more omnidirectional to our human ears and thus indistinct where their sound origins go. High frequencies on the other hand appear to originate from a very tightly confined location, one that is easily pinpointed. We can thus appreciate that the quality of upper midrange to treble performance in our rooms is important to the convincing recreation of recorded space. Stereo relies on two discrete sound sources (the speakers, which each tend to be comprised of multiple transducers). Our ear/brain mechanism has to assemble the left/right data in such a way as to - um, hallucinate the apparent presence of ghost performers between the speakers, each in clearly assigned spatial relationship to the others, front-back and left-right.

This happens via the arrival time offsets caused by the different path lengths which sounds travel to each ear, both from the closer and farther speaker. Martin Schützenauer contends that if the speaker-to-speaker distance is known -- an average of 2 meters in standard rooms -- a clever designer can manipulate the phase behavior of his treble system such as to simulate a sound origin exactly in the middle of the room, as virtual single point source. This is regardless of the usual room interactions which omnis and bipolars would deliberately exploit but which would be different from room to room. It also explains why the Wave Control would work affecting both drive units inside the PAC module simultaneously. It doesn't rely on sidewall reflections the way we might assume.


This now ends our detour into conjecture. Except to confirm that this system works without understanding word one about it. Again, my first exposure to WLM's PAC system in 2005 had me write this sentence without knowing any technical background: "The most powerful impression here was one of complete annihilation of the usual differential between left, center and right image density."


Clearly, if you want the best from WLM, you need an active (direct-coupled) model outfitted with their SUPER-PAC tweeter. That may not necessarily mean a floorstander. A superior monitor augmented by the right sub will nearly always beat the equivalent floorstander in speed, greater absence of box coloration, better dynamics and higher power handling. In fact, word has gotten around that Hannes privately listens to a one-up Grand Viola Signature monitor. He's a monitor/sub man. And it's two up. Dutch WLM dealer Theo Oosterhuis has a pair too. Now his clients have heard it. Orders are coming in for a product that does not officially exist. Yet. There's the old law of demand and supply though. It appears a GV Monitor will soon make its official launch. Word leaked, discerning ears want it. Desires can manifest things. Incidentally, the Grand Viola and Duo subwoofers use Birch plywood for their enclosures, all other models MDF with solid hardwood bracing.


Adds 55-year old Theo: "I've been an audiophile for some 35 years now. I owned my share of electronics and speakers. Think just about all of the standard names in the business, about 40 pairs of speakers for me and even more electronics. Eventually I recognized that I am a tube guy (especially single-ended designs) and analog is my preference. My first encounter with Hannes goes back to the early nineties. He had some interesting, very exotic tube amplification as a retailer which I was looking for. We set an appointment and I drove from Holland to Austria to visit his studio and audition the amplifiers (which I ended up buying). From the moment we met, I knew that he was not the usual retailer but someone with a real musical interest and very good hearing. His ability to set up very unusual systems with a very musical outcome was exemplary.


"Then in 2001, both as exhibitors at the Frankfurt Show in the Kempinski hotel, we met again. I told him how disappointed I had become with the whole High-end thing. The more expensive the system, the more disappointing the outcome. Hannes shared my sentiments about mainstream sound but told me he'd heard an unusual speaker from an Austrian engineer that really had him enthusiastic. He invited me to have a listen to this speaker after hours. At 10PM that evening, I saw someone entering the hotel carrying some wooden ski sticks (stands) over his very broad shoulders who later came back with a very strange and ugly pair of monitors. I thought he was some guy setting up a cheap pro-sound system for background lounge music somewhere.


"After about 30 minutes, Hannes reappeared in the bar. He told me he'd completed the setup in his demo room. He'd taken all the exhibit stuff out just to set up the mystery speakers. I entered the room and you guessed it, there were those ugly monitors. I feigned interest to stay polite. Martin explained the system, an actively crossed-over monitor/subwoofer affair with a weird-looking high-frequency concoction on top of the monitor. Then music played and my mouth fell open. The sound was full with real presence, a midbass with real impact, dynamics to scare you and high frequencies with none of the thinness and whiteness you normally hear from playback. There was an immense amount of air and dimension to the sound that I had never experienced before. I was totally swept away and listened for hours on end. Stranger still was the fact that this system was set up with whatever electronics happened to be on hand. The cables were nothing special, just some thin generic $15 copper wires. The electronics were good but not extravagant - a pair of Manley 300B monos on the midrange, Manley Stingray on the highs and a Martin-built transistor amp on the bass with a YBA CD as source. That demo was the best sound I'd ever heard, period.


"Even though they were prototypes and I had no idea how WLM would develop, I told Hannes and Martin that I wanted the first production pair, ugly and all and at whatever cost. They had a real ball that night. I went back to my exhibition room afterwards and listened to my own $150,000 retail setup. I couldn't figure it out. The Austrian contraption so put to shame my so-called ultimate high-end display that I really considered breaking it up and leaving for Holland the next morning." Four years later, Theo is the proud owner of the second pair of WLM Grand Viola Signature monitors in existence, basically a seriously souped-up Diva without coaxially mounted tweeter but the top-mounted SUPER-PAC instead (higher efficiency, broader dispersion and superior impulse response over the standard PAC module plus all silver cabling).


Another case of how desires shape destinies is WLM's engineer Martin. He built his first loudspeaker at the age of ten. Along 35 years of obsessed tweaking, he built himself amplifiers, preamplifiers, phono stages, output stages, input stages, micro stages and more but concluded that the loudspeaker always represented the weakest link of the chain. He finally decided to tackle this problem head-on. Being a fiercely competitive athlete, he insisted on learning to design a speaker which he didn't feel suffered compromises. This involved decades of immersion into filter theory, transfer functions, acoustic theory, psychoacoustics and insights into how human hearing localizes sounds. Spending plenty of time, money and energies on his obsession, his summary conclusion became that it's not merely measurements, lowest possible distortion, the most expensive and exotic materials which determine the sonic quality of a loudspeaker but an equilibrium between all constituents that must conform and appeal to human perception. After having tested many of today's exotic drive units which upscale speaker houses take great pride in using, Martin merely shrugs his shoulders. "We tried most of them. We're not afraid of building expensive speakers if that's what it takes. You wouldn't believe though how many of those expensive drivers simply failed our admittedly tough tests. They broke, never mind sounded inferior.
People may decry our reliance on Eminence because their stuff isn't expensive. Take my word for it - Eminence drivers outperformed anything we've put against 'em. These units are super reliable and nearly the epitome of a growing personal suspicion that with drivers, more often than not, more expensive nearly predicts poorer performance." Not a statement the trophy audio hunters will embrace with conviction. For the SUPER-PAC modules, WLM goes through 100 drivers to come up with at most 4 to 5 systems. That's how critical very close tolerance driver matching is for these purposes. All PAC-fitted models come as clearly marked left and right speakers which aren't interchangeable side to side.


About his high-frequency system, its inventor added: "Because the complex interactions between phase behavior, impulse response and frequency response I'm exploiting won't show up in conventional measurements, I had to develop my own suite of measurements -- many hundreds of them combined -- to document the actual performance of PAC. In other words, you have to first know what to look for before you can design specific measurement procedures to quantify it. Otherwise you'll measure the wrong things. You'll be baffled that what you so clearly hear shows no correlation on the test bench. It does. But you won't know what to look for and thus miss it, period."



On that subject -- knowing what to look for -- if you're playing in the price league of the Diva Series, the floorstander isn't necessarily the better choice over the Monitor as you can appreciate by now. Add the Diva Control to further confuse the usual implications of hierarchy and superior performance. The moral of this story is, don't let your loaded wallet or preconceptions (on size or anything for that matter) decide. Listen to your ears instead. They know. That's the unpopular law. Which now concludes our introduction to this loudspeaker company, its principals and lineup.