As far back as I can recall I’ve always enjoyed taking a look under the hood–from automobiles to audio. So when I was invited to have a peek at some of the technology that goes into Wilson Audio loudspeakers, especially in light of TAS’ plan to have me review the Sophia 3 later this year, I jumped at the opportunity. We’ve all innocently joked at one time or another that loudspeakers are little more than a box full of drivers–as if, what’s the big deal? Spend a little time with Wilson’s Director of Sales and Marketing, John Giolas and I was reminded just how big a deal it is. Here is a brief photo essay of what I’m talking about.
Located in Provo, Utah, the current factory reflects Wilson Audio’s enviable growing pains. An expansion begun two years ago increased square footage from 28,000 sq ft to 40,000 sq ft.
Enclosures are milled on-site. Period. Every plane is leveled to within 4/1000 of an inch. Note in the below image the feeler gauge looking for “daylight” and not finding any. Throughout the construction and final finish process these parameters are rechecked. Obsessive? You bet.
Loctite cabinet adhesive is used unsparingly. The cabinet structure is designed to balance three criteria– hardness, damping and to achieve a narrow-band monotonic resonance which can later be addressed via bracing and crossover optimization.
X-Material (pictured above; it's a high pressure composite of mineral, polymer, carbon and paper) is very monotonic with a resonance of approximately 1.2kHz. It’s downside is that the relatively high resonant frequency is not ideal for some midrange modules so Wilson developed M-material (now in its 5th Generation) for the Maxx Series midrange enclosure and S-Material for the Sasha which uses a bit less carbon in the composite and is 20% less rigid than X. Combinations of both S- & M- material is implemented on the Sasha and Sophia loudspeakers. S&M?
In terms of the stages of development the first 20% of the speakers evolution is done in the virtual domain but once the basic skeleton of the enclosure is determined full scale mock-ups are constructed, tested, bracing patterns adjusted and refashioned–not unlike the way an acoustic string instrument would be crafted by its luthier.
(above) Thor internal bracing pattern.
(below) Dual bed, twin head air cooled system for drilling, & routing X, S, & M Material enclosure materials. No pieces are wasted. This image shows grille material destined for a Sasha speakers with Wilson Logos being cut-out to be used as painted-disc samples for customers to peruse. Drill bits have short life-spans–perhaps a couple hours and can cost up to $450 a pop.
(below) X-material in clamping rigs
(below) Sophia cabinet depicting overflow of glue and raw edges prior. Overflow insures there are no air pockets in the seams. Immediately following the initial application of glue each speaker travels to a curing room where enclosures spend three days in a sauna-like 100 degrees. Sanding tolerances are extreme and this second image shows the application of a SuperGlue/Corian powder combination to seal the seams prior to finish sanding. This substance dries almost instantly. Wilson reports virtually zero seam-failure.
Gel-coat is a marine-grade vinyl/polymer which like a traditional primer creates an impermeable shell in preparation for the finish and clear coats yet is more elastic than normal primer. First however this application is sanded down to 4/1000 of inch. Typically seven coats of paint anoint a Wilson speaker. The final three coats are clear coats which help provide the deep luster and add resiliency. Custom colors, stencils, pretty much you name can be applied and in some instances the process may take up to 12 steps. Curing time is seven days. The spacious paint rooms sport massive fresh air recirculation technology and are controlled for both temperature and humidity.
(below) This is followed by wet-sanding.
I inquired whether flat or matte-finishes, like those popping up in the high end automotive world have increased in popularity at Wilson as well. For reasons I'll never understand, the answer is yes. Image (below) depicts clear-coat black with date and employee signature.
A nearby metal-milling subcontractor supplies 60-70% of its output to Wilson Audio including all aluminum, stainless components. Cables are delivered in raw bulk from Transparent and are built to specification and assembled totally in-house. Crossover design is proprietary and no photos were allowed but Giolas expressed the particular and obsessive tolerances that Wilson mandates in its designs–0.5%. In order to achieve these tolerances no two crossovers are necessarily physically identical in terms of capacitors as Wilson never takes cap values for granted. Thus I saw varying combinations of small and large caps designed and tested to precisely match Wilson's reference x-over boards.
Later on we were shown into an area that houses Wilson's in-house photo studio which Giolas personally oversees plus a somewhat improvised Wilson Museum. Here was the original Tiny Tot prototype and this rear view of the legendary and rare WAMM.
(below) TAS Reviewer Jacob Heilbrunn stands beside the original XS subwoofer. Seven feet tall, 900lbs (the XS, not Jacob)