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|Resonance control -- or more accurately, vibration attenuation or isolation -- is a highly complex and sophisticated science. All the available data and research amassed thus far really pertain to industries other than audio. Precious few are the audio companies who not only understand the science involved but have the access, aptitude and know-how to first identify the relevant measurements to make and then to conduct their own testing procedures as they apply to our intended usage. Far more prevalent are marketing-driven firms who befuddle their audience with impressive terms like "mechanical impedance" and "energy drainage" and "constrained layers", to first sell concepts and then products that conform to these concepts. Should you read somewhere for example that viscoelastics are good only as door stoppers, run as fast as you can. Then ask yourself how come that all mechanical fixtures inside Trident submarines use viscoelastic decouplers to make these aquatic hi-tech marvels as silent as ghosts. Especially in this field of isolation accessories for audio -- though they truly are far more than mere accessories if properly engineered -- it is vital to crank up your own BS sonar to its highest sensitivity. Take serious any blips that show up on your common-sense radar and don't hesitate to ask questions and insist on verifiable proof for claims made.
Read up on the background of the individuals who run Silent Running, HRS and Grand Prix Audio, for example. Without fail, you'll find that their applications of specific technologies rely on prior experience in other industries where vibration attenuation has been a very serious science for ages. Whenever an audio application relies on solutions not found anywhere else, you can pretty much conclude that it's at best marginally effective if at all. Military, aerospace, medical, automotive, heavy construction and seismic control are all sectors that have spent far more decades and millions on this subject than all audio companies plying these vibration attenuating fields combined. These industrial sectors are our peers in this regard. Audio can merely apply their prior findings and solutions and adapt them to become optimized for the frequency range and impact scale that concerns us. Forget about inventing anything novel per se. The most novel anyone could -- and should -- hope for? That honest engineering might migrate from those fields into audio to displace some of the cocked poppy weeds that grow rampant here.
EquaRack belongs in the category of mostly intuitive rather than measurement-driven engineering. Joe Ciulla did not generate any measurements on his assembled rack during any stage of the design process. Nor did he purchase or borrow competing solutions to survey the scene or later conduct side-by-side comparisons to monitor and steer his own design progress. His focus first was on the concept of lateral isolation which he believed to be important for audio applications. This led to the development of his ultra-precision dual-race (top and bottom) bearings. Already a year ago, viscoelastic damping was part of that equation but it has since grown more prevalent and sophisticated. Its implementation is based on generic performance specifications as provided by his material supplier. Shy of subjective iterative listening, there are no self-generated tests about how these parts actually measure and perform when they're integrated into the assembled rack as a system. It's thus fair to state that the design genesis here was based in equal parts on prior assumptions and subsequent engineering focused on parts rather than the whole system. There was no in-house test-bench data acquisition from the word go to quantify the performance of successive prototypes and assist in deciding on the desired mix of performance, aesthetics, convenience of assembly, ease of manufacturability and target retail price.
EquaRack combines three particular design elements. The first is structural rigidity by way of the framed exoskeleton. Its bolt/channel-nut joints [above left detail] take 50lbs/ft pressure for quasi cold weld connections. In practice, it means you could take a long handle extension for leverage and crank down until you hear the metal screech. That's in fact Ciulla describing how to know when you're good. Are you one of those wrench maniacs who routinely sheers off speaker binding posts with too much applied torque? EquaRack welcomes you. Take on someone of your own size. Your wrench will snap and your wrist break before you make so much as a dent in this frame. One assembly challenge is to avoid a parallelogram. After putting everything together on the floor and then rightening it up, you will likely notice that the uprights won't exhibit a perfect 90-degree angle with the cross members to create a leaning-tower-of-Pisa effect. Loosening the associated bolts enough, you could in fact fold the whole structure down flat [not recommended but illustrated to show how the parts don't automatically lock into perfect right angles]. Before you thus mount 105 lbs of raw frame atop the isolation bearings, make sure everything's true and square.
|The second design element is lateral freedom of motion. The associated idea is that vibration propagates through motion and that Newton tells us how every action engenders an equal but opposite reaction. Think of the popular executive desktop toy called,
|fittingly, Newton's Cradle (or less reverently, Newton's Balls). Five metal balls, one right behind
|the other, hang suspended via filament from a frame. You bounce the first ball into this row and the last one will pop up and the whole thing turns into a clickety-clack pendulum-type affair. Note how the first ball stops nearly cold in its tracks, transfers its energy through the other balls and into the last one that separates from the pack, swings out and returns to resume the process. In general, you've got a few options to stop a moving ball. Slam it into something rigid in which case the ball will bounce right back at you. Slam it into something that can move and rather than bounce back, the movable item will run with the impact. Or slam your ball into an absorptive viscoelastic that accepts the original impact without reflecting it back. Returning to our desktop toy, its clickety-clack pendulum takes a long time to exhaust the input energy before it comes to a complete stop. It's not a perfect "closed-loop" perpetuum mobile but still highly inefficient at dissipating/converting energy. Of course, that's precisely its appeal - a bit of visual distraction for the bored executive while chewing pencils. But insert just one piece of viscoelastic between two of the balls and the whole toy will stop working as intended. This brings us to EquaRack's third design element, viscoelastic damping.
The way viscoelastics are applied to the bearings is by way of a second stacked story. In that dimension (below in the floor bearings, above in the component bearings), these nubs make for hardly any lateral damping unlike the horizontal-domain decouplers between uprights and triangular cross members of my GPA Monaco. Activating the ultra-sensitive EquaRack bearings even with the slightest push -- and without yet the additional load of weight-bearing components -- can take upwards of ten seconds before movement becomes too small to discern with the naked eye. This becomes further exaggerated with bearings that are mounted to the top tier. Any motion introduced at the bottom is amplified on the uppermost tier. That sensitivity is testament to how precisely those bearings are executed, how polished, hard and even the Tungsten Carbide races are. Now conceptual assumptions enter the picture. Is lateral isolation a vital design parameter of audio racks? After all, we don't bang into them while we listen. Is this particular cure then for a real disease or merely one that's imaginary or at best tertiary? If the disease were real and primary, are expensive precision bearings in fact the most expedient and cost-effective cure? Without devising comparative tests to quantify measurable effects of different solutions, this question simply cannot be answered. Period. That's why I earlier called the EquaRack approach based on intuitive engineering. Once you start with the assumption that lateral isolation is king, building audio's best isolation bearing with only marginal self-damping properties becomes the solution. Naturally, marketing propaganda now has to use it as a unique selling proposition (and having worked in that sector, I have some pretty good notions on how that could be done). However, what isn't asked though it should be asked? Is it necessary in the first place and truly effective and best in the second?
Mounting the assembled 105 lbs rack atop the isolation bearings so everything's perfectly aligned and none bind up especially if spike adaptors are used is somewhat challenging. You probably want to account for some wall clearance behind the rack while doing it but once finished, you cannot push the rack flush up against the wall since it's solidly spiked now. Leveling out the spike adaptors via their open hex ends becomes vital to assure that the load's downward pressure compresses the blue pellets underneath the bearings equally to get a perfectly even gap [upper right detail]. The next step involves leveling the actual rack above so that its cross members are parallel to the floor. This is done via the 5/8th bolts that connect the upper half of the bearings to the uprights. I'd say set aside about 3 - 5 hours for total setup from unpacking and reading the very lengthy instructions to assembly, setup and weight-matching of the component mounts. If you choose to use the combination mounts, figure on adding 3 inches of height for component clearance between tiers. If you change components and significantly alter their load-bearing weight, use the 5/8" threads to jack up the stand and temporarily park it on spacer blocks or phone books to change the number of blue pellets in the floor mount.
Does your notion of good engineering include not merely audible performance but ease of use as well? Then Equarack is clearly not a premium example of truly elegant engineering. This design is klutzy and unwieldy and makes not only significant demands on prospective owners but also asks for certain oversights. It's as though Ciulla hadn't fully thought through all of the practical implications before he committed to his particular design tangent. I find this especially curious in light of the fact that Finite Elemente and Grand Prix Audio, arguably the two established heavy hitters with market share in this genre, existed well before EquaRack ever entered the picture. If you wanted to compete successfully in this market, wouldn't you try to design something that didn't suffer the perceptional hurdles of "less attractive" and "far more complex to assemble" than two of your keenest competitors? Since this known owner of GPA's Monaco was especially chosen to conduct this particular review, am I not expected to approach my evaluation in this critical and comparative manner? Incidentally, to this day, Mr. Ciulla has not compared his Equa rack to either Finite Elemente or Grand Prix Audio or HRS to determine for himself where he stands with regard to audible performance. This signals unusual faith in the superiority of his own concept.
With these considerations out of the way, on to my subjective listening evaluation. I deliberately minimized my system to have merely two components to move back and forth until I got a solid fix on things. I also picked components that I had never listened to before as a system. Whatever the sonic outcome, it'd be completely fresh and news to me. I'd be able to concentrate on the raw differences made by the racks, not complain that one didn't sound the way I'm used to. I opted for the absolutely massive 65 lbs Consonance Droplet CDP 5.0 with variable outputs directly into Deja Vu's 300B amplifier into my Zu Cable Druid Mk4s via a single-wire run of Zu's Ibis. The interconnect was by Siltech, the power cords Crystal Cable Reference. Swapping between racks would take about five minutes. The FirstWatt F1 found itself on the Monaco simply because I ran out of space to put it anywhere else in my room after I'd taken down the usual reference rig. Consider it free ballast in this context (sorry Nelson).