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It's impossible to tell the story of the room construction without at least mentioning the Wilson Alexandria X-2. First-time visitors to the room are instantly drawn to the speakers. They are complex yet elegant and visually compelling. Few have seen and heard the X-2 and even fewer have watched their assembly. Several friends and readers have asked about the speakers so I’ve added this chapter to give a little insight into the assembly and setup of these amazing transducers.


First let’s get my bias out of the way. I consider the X-2s to be the finest production speakers in the world. There are many speakers vying for state of the art and they are spectacular in their own right. Some may exceed the Wilsons in a specific attribute but taken as a whole and set up properly in the right acoustic environment, this is good as it gets for me. You could write a book about the uniqueness of their design and exquisite sound. This however is a chronicle of my room assembly, not an X-2 review. Perhaps I can do that later. For now I’m going to focus on assembly and setup while briefly touching on one of the unique elements of this speaker design as it relates to room acoustics and setup.


Let’s talk about assembly. With the finished units weighing 600 pounds, assembly is a job for professionals and Terry Menacker and his technicians from Overture Audio were the experts. The process is far more than just bolting box A onto Box B in rote fashion. The design and flexibility of the X-2 mandates a unique installation in almost every listening room, which we will get to shortly.

The speaker arrives as a set of modules – bass, midrange and tweeter. The modules are made from Wilson’s proprietary X and M materials and let me assure you, they are solid, dense and non-resonant. The sound of a knuckle rap to the side produces a thunk closer to lead than any MDF variant  How these modules interact is part of the uniqueness of the speaker. While I can't state for certain that no two Alexandria installations are identical, it’s certainly possible. The reason for that Wilson calls aspherical group delay. It began with the X-1 and now expanded in the X-2.


Complex multi-driver speakers with wide dispersion have significant advantages as well as inherent limitations. In all multi-driver systems, each transducer has its own dispersion pattern which mixes with and overlays the sound from the other drivers to create all manner of amplitude, phase and timing issues. What starts as a uniform and coherent music signal is split by the crossover, output by a series of individual drivers and then reassembled into a hopefully coherent musical waveform by your brain.  Due to design limitations in many speakers, it’s difficult if not impossible to maintain the proper time and phase relationship of the original signal. This results in the difference between merely good and that tingly scary-good sound when a performer holographically appears in front of you. Wilson uses the analogy of wide-angle optical lenses, designing systems that allow the sound to be focused over a wide variety of distances and listening heights.


There is a series of three midrange and tweeter modules sitting atop the bass modules. Each of these pivots up/down and slides in/out based upon the height of the listener at the seating location and the distance from the listener's ears to the speakers. I've long forgotten my college statistics for calculating total possible combinations but each module has up to five different heights (actually polar rotations) and 33 different horizontal locations, allowing the X-2 to be optimized in rooms with listening distances from 8 to 26 feet. 


Wilson uses what they call a series of timing tables, charts and graphs to convert the listening distance to spike length and horizontal spike locations. The length of the spike determines the height/rotation of the speaker module, the location gives the in/out distance of each module for the proper location of each assembly. These are critical dimensions where the difference between a single module detent is measured in fractions of an inch. It's a complex and sophisticated system.

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In my room, the listening distance is 12 feet and my ear height is 40 inches off the ground. The correct spike length for the high-frequency module is ‘D’. Using these same distances and following the graph, you get detent spike location 24. Spike length determines the amount of rotation per module and the spikes rest in a track of indentations designed to receive them. The same procedure applies to all three upper modules. This is one of those processes virtually impossible to describe properly but making total sense in the observing. It's one of those ah-ha moments that just clicks into place.  Having seen and participated in the installation process, I can now fine-tune the speaker and reset the modules myself using the instruction manual and timing tables.


It’s difficult to gain a full appreciation of the process by simply viewing my photos. The sheer number of pieces and their complexity might offer the impression of a cluttered random assembly. The reality is quite the opposite. The speakers are assembled in a very precise linear fashion. Unfortunately my photos don’t capture that. Therefore, look at them as a minor glimpse into the process rather than a true documentation.

Once assembled, we need an initial location. While an equilateral triangle between speakers and listeners is always good, Wilson has their own system which involves finding what they call the Zone of Neutrality. This two-person process includes one person at the listening location and the second person standing against the front wall roughly behind where you intend to position the speaker. The person against the front wall begins talking moderately loudly in a consistent voice. That person then slowly walks out into the room parallel to the side wall. Initially the voice will be unfocused and have Wilson calls chesty due to the negative boundary effects of the front wall. Moving away from the wall, the voice will open up with increasing focus and ultimately become more tonally correct. The floor is marked at that position. Continuing for one to two more feet, the voice will eventually lose focus due to interactions with the opposite wall. The floor is marked again, giving the outer boundary of the target window. The same process is repeated for the side wall by walking out from it through your floor marks parallel to the front wall. With the two additional side-wall floor marks you now have a rectangular zone of neutrality to provide a very good starting point for your speaker placement. 


There are countless rules of thumb. The aforementioned equilateral triangle or placing the speakers at thirds or fifths dimensions from the nearest walls are good but just starting points. In my specific case, I was fortunate to have Terry and Overture’s expertise to draw on. Terry’s initial placement in the zone of neutrality was very close to the final position. Unfortunately there is no shortcut to the painstaking incremental movement of the speakers at sometimes quarter-inch increments.


After finding the best location, I used a disc with in-phase and out-of-phase signals. The test record works well. I play the out-of-phase track and incrementally move the speakers to achieve the most diffuse sound possible. Close your eyes and you should not be able to localize any sound, meaning zero soundstage and imaging. If you can pinpoint the sound, move your speakers very slightly. With the out-of-phase sound, you should be totally engulfed in sound and with your eyes closed, the sound should not appear to be directional but simply exist in the room. The closer you can come to this effect, the better your speaker location will be for superior soundstaging and imaging with normal in-phase sound.

Two months later I was done tweaking and the speakers' casters were replaced with spikes to lock in the installation. Where was the final location?


As shown above, the distance between the speakers is 85% of the distance to the listening seat, 37% from the front wall and 29% from the sides. 

There is no way one person can install the X-2. It requires several strong men. In fact a single person attempting it risks serious injury. At over 600 pounds, even a small slip can be dangerous. Wilson dealers are well trained and use several people to move these monsters around.


With that said, the installation manual is so incredibly well written that an owner and a few friends could actually assemble these using just the manual.


This is not a recommendation, just an observation. From my experience, it’s far away the best product manual I've ever seen for any audio equipment in my entire life. When it comes to instruction manuals, there is Wilson and then anything else ever written.  Beginning with the lush padded binder, the manual explains not only how but why. From detailed close-up drawings of the installation, pages on acoustic theory, positioning and troubleshooting, the manual—like the speaker itself—is a spectacular example of what can be done. It should become the model for the industry.


With the speakers assembled and initially positioned, the next chapter moves on to one of the primary ASC acoustic tools – the MATT test.

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