Realization

Grand Prix Audio's conclusions

Mass: We found that even the heaviest bulkiest equipment supports on the market couldn't apply enough mass mated to the requisite attendant damping properties to effectively attenuate resonances. The amount of ballast that could be filled into the hollow metal columns proved insufficient for proper damping. A larger cross-section and increased wall thickness would be required. Additionally, mass without damping is a sure recipe for defeat.

Anyone whose feet have ever been tickled by bass notes vibrating the floor understands that even thousands of pounds of concrete (presumably damped by the soil below) are insufficient to quelch the loudspeakers' output. What's more, the concrete substructure transmits vibrations across large distances (into other rooms) relatively unattenuated. GPA's designs clearly could not primarily rely on mass to successfully isolate components from environmental vibrations.

Suspension: Airbladders must be precisely matched to whatever weights are supported to avoid acting as essentially undamped springs. Air suspension properly implemented was one of the most effective isolation controls pre-GPA. However, limitations remained.

Take a racecar. Its worst enemy? The tire. A tire by nature is a largely undamped spring that goes into oscillation with every unevenness encountered.

The only inhibitor? The friction created from sidewall deformation and the contact patch with the asphalt. The only damping occurring with air suspension is the friction created by the mass loading it - a primitive friction shock as used at the turn of the last century in buckboard wagons and early automobiles. The problem with spring suspension is its natural tendency to cycle endlessly until it is stilled by converting motion into heat. Like a bell, a spring is a very resonant structure. It requires a damper to control its motion. Ever since computerized hydraulic shock systems were banned from racing, elaborate mechanical systems with thousands of adjustable valve settings account for optimized control over the springs as defined by the frequency and amplitude of the surface imperfections of any given racetrack. Taking into account the high maintenance variables involved in making traditional spring suspension work properly, we decided against relying on it in any primary fashion. Instead, we would suspend our shelves using non-metal spring suspension with integral damping.

Damping: We found damping to be a highly critical aspect of the most effective systems. We thus concentrated on implementing it in a senior function in our designs.

Coupling: We determined that point loading to reduce resonance transfer was moderately effective. Hence we embarked on developing a new and unique coupling interface dubbed True Vector coupling, which is described in detail in our White Papers.

Decoupling: Our reviews of existing decoupling schemes concluded that various Sorbothane accessories and their derivatives as used in heavy industry (when utilized correctly) are the most effective decoupling devices. Moreover, our tests showed that these damping interfaces can attenuate high percentages of energy from the components themselves.

After using commercial shaker tables for initial prototype testing, we quickly discovered that the efficacy of our new design went as far as damping the actual shaker table to render precise test data impossible. We were forced to construct our own shaker table in conjunction with high-sensitivity millivolt accelerometers. We then measured our own prototypes as well as all manner of competing designs using controlled inputs of actual music signal while recording the amount of attenuation produced. Once we had developed our high-sensitivity measurement setup, we could clearly quantify up to 45% improvement of resonance attenuation that our designs produced versus the most successful air-bladder suspension designs on the market at the time.

Integration: As with our prior racecars, we believed that the chassis itself should be a significant contributor to the overall performance and provide many of the damping functions we would require for optimal efficiency. We knew from our testing that we couldn't manufacture a structure stiff and rigid enough to not vibrate at all. Damping would be key. This pointed the way to a flexible, fully independently-suspended, highly damped structure that would abandon the popular high-mass ideal and require sophisticated composite technology. We had in-depth experience with modern carbon composites and identified them as the perfect self-damping materials of superior stiffness yet light weight and a given ability to be elegantly shaped for sophisticated appearance. Finite element analysis would be used to design a structure with optimal damping properties and enough innate flex yet sufficient strength to support the specified loads.

Multi-Stage Isolation

Stage One Isolation: A robust 304 Stainless steel spike with thru-hole for leveling key (provided) and hefty 3/8" mounting stud provides the perfect starting block toward superior vibration attenuation and assures a solid coupling contact with all subfloors even through multiple layers of thick carpet and carpet pads. A hefty locknut guarantees permanent adjustments for structural integrity.

Stage Two Isolation: Large 2" diameter, thick-walled 304 Stainless steel support columns with self-damping Aerospace coating attenuate vibration migrating from the floor upwards through the columns. Even without ballast, the wall thickness and hitech coating already prevent the ubiquitous ringing and transmission behavior of inferior metal tubing. Lead/sand filling bestows additional benefits but to a far less pronounced extent than with designs lacking such detail-intense engineering.

Stage Three Isolation: A unique twin O-ring damping concept decouples the column closures from the actual columns to create another dissimilar material juncture against vibration propagating upwards into the higher modules.

Stage Four Isolation: Our research led us to develop the unique True Vector coupling interface implemented between shelf modules 2/3 and 3/4. This innovative and attractive pin/bearing interface replaces the far less effective spike/cone feature that always suffers from insufficient manufacturing tolerances to cause poor force fits that introduce permanent material stress, deflection and visible deviation from perfectly perpendicular load paths. The True Vector interface is our adaptation of industryproven single-ball constant velocity joints.

Stage Five Isolation: Rather than bolting the cross members directly to the columns, our innovative viscous damping interface acts as yet another decoupler and assists the primary composite structure in its self-damping properties as well as provides necessary degrees of freedom.

Stage Six Isolation: Our Carbon fiber composite triangulated primary support structure offers far higher load stress compliance and none of the metal fatigue degradations common to the usual metal cross members. Lacking their directional crystalline grain structure, our polymer-toughened 90-degree Carbon fiber weave -- similar to the far stronger cross-fiber arrangement of plywood versus the directional grain structure of natural wood -- turns each strand into a constrained-layer member.

This offers thousands of load paths and yields a stiffer, lighter chassis without the ringing associated with metals which -- like bells -- are really energy transmitters, not dampers. (Ever wondered why church bells aren't made from wood or rubber?) Like Go-KARTs that lack primary suspension and use chassis flex compliance instead, our Carbon fiber struts combine shock absorption and spring qualities for the ultimate dissipation of resonant energies.

Stage Seven Isolation: Sorbothane dampers that are weight-matched, from shelf to shelf, to the specific components supported create the next transmission barrier. They nest in pre-formed hollows where the Carbon fiber composite cross joists meet. By adapting their compliance to the components, we are able to maximize the performance of our design just as we would adjust the shocks of a race car for any given track.

Sorbothane was first developed in the 1950's in response to a Navy contract for nuclear submarine skin coating. Due to extensive and ongoing research enabled by such government funding, Sorbothane's application-specific properties down to very finite degrees are well documented and can be optimally tuned to diverse usages and intended results. Basic properties of this hi-tech, over-engineered material may be studied as jpgs 1 / 2 / 3 or a pdf file. These documents remain the property of Sorbothane/Trelleborg Company and are reproduced here in their original form for your convenience.

Stage Eight Isolation: By using an Acrylic shelf in combination with component damper pads, we transform the shelf proper into the final vibration defense for the quietest, most isolated platforms in the business. Our acrylic shelves are second only to our Carbon-fiber composite Formula Shelves. These shelf materials further assist in attenuating component-generated vibration to prevent transference to other components housed on the same support unit.

Shelves are available in 1/2" and 3/4" thickness determined by component weight, and in clear (standard) or smoked and black (upcharge) finishes. Since our standard shelves are 23.25" deep to accommodate even the largest components, ultra-short interconnects between standard-depth components placed along the forward edge of the shelf will be too short to clear shelf depth. To accommodate such scenarios with interconnects shorter than the standard 1m/3ft, we offer cable management holes wherever in the shelf you care to specify them.

Stage Nine Isolation: Our Apex interface replaces the stock spikes for significant performance enhancements. The Apex is a pyramidal cone whose tip features a recessed cup. This recess houses a 1/2" ball bearing in such a way as to utterly avoid the frustrating instability and "component jitter" of competing bearing- based devices that cause supported gear to sway and move when barely touched. The high-pressure vacuum-cured Carbon fiber outer skin of the Apex is decoupled from its Carbon fiber base/core via a proprietary dampening polymer that we codeveloped with aerospace applications and materials sciences engineers. When Apex is used as the floor interface for our stands, the spike is replaced with a knuckle adjuster, Leveler, that securely surrounds the ball bearing but adds two degrees of freedom to the structure.

Stage Ten Isolation (exclusive to Monaco SE): The 2" diameter upright stainless steel support columns add 1-inch aluminum inner tubing to contain a 3/4" ring damper of the same custom polymer first developed for Apex. This polymer is poured into the airspace between inner and outer tubing. The hollow core of the inner tube may additionally be filled with ballast or lead shot.

Stage Eleven Isolation (optional): The Apex interface doubles as an ultra high-performance component footer whose standard- size ball bearing allows experimentation with various after-market isolation balls to fine-tune the effects of Apex.

Multiple degrees of freedom
Like a sapling surviving strong storms with flexibility and bending, our top-line Monaco Modular Isolation System shelf incorporates multiple degrees of freedom to help dissipate absorbed resonance through flexible movement within the unique, fully independently suspended and damped structure.

For details on the science behind our design, continue on to our White Papers.