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Critical Mass Systems Sotto Voce Equipment Rack

Sometimes, if you’re lucky, you acquire a component or accessory that is so good the thought of replacing it never comes to mind. You install it, have a listen, and say to yourself: “Well, that’s that.” For me, this happened when I replaced whatever racks I was using to support my system (see, I can’t even remember, so thoroughly did I jettison them) with a contraption from Goldmund. Back in the day, when Goldmund was blazing trails that others are still following, the company made a rack system built from state-of-the-art materials and with a clever method of isolating shelves from each other. Isolation of the equipment from the shelves was handled by the superb Goldmund Cones, which were an integral part of the system. I put my gear onto those racks, had a listen to their effect, and I was done. The sound had improved substantially in every way.

Since then, understandably, racks haven’t been on my radar. Oh, sure, over the years I have read the glowing TAS reviews of some pretty fancy-shmancy racks, like the Critical Mass Systems Maxxum. But they tempted me not at all, given their $40k price tags and my satisfaction with the Goldmunds. Truth is, I probably would have lived happily with those racks right into my twilight years if not for their bête noir. You see, these things are ugly. I mean seriously ugly. Massive blocks of sharp-edged black iron form the frame, which supports equally-square, equally-black slabs of methacrylate shelves. On the style-ometer, the Goldmund racks earn a solid zero.

Why is this relevant, given that the racks perform so well from a sonic perspective? Well, I happen to believe that aesthetics contribute mightily to the pleasure of this hobby. Top-notch audio components don’t just sound good; they look the part, oozing craft and workmanship and, yes, style. Some are even sexy (“audio porn” as my buddy Karl Schuster calls them). In my view a rack should show off these components to best effect, and also show off the system as a whole within the room. This is why, despite the eyesore-Goldmund’s sound, I have rankled at inhabiting it with the stream of gorgeous components I am fortunate enough to have flowing through my home. The equipment—not to mention the room—deserved better.

So when Critical Mass came out with a brand new entry-level rack, the Sotto Voce, the first thing that intrigued me about it was not its potential sonic benefits, which were purely theoretical at that point, but rather its looks. Other CMS racks lean toward a purposefully industrial style (though not with the brutality of the Goldmund stuff), but the Sotto Voce has a much friendlier, warmer, and more inviting look. This is because, while metal connections within the frame are milled from billet aluminum, the frame and shelves themselves are made of good old-fashioned wood. Sapele African hardwood, to be exact. Not high tech, to be sure, but purposefully chosen and certainly appealing to the eye. The rack also appealed to my value detector. Unlike CMS’ ultra-pricey top models, a four-tier SV system with shelves costs just $4500 ($5500 if you’d like it in black). That’s right: the SV is one-tenth the price of the top-line model.

I took delivery several months later. By the time CMS’ affable and deeply-knowledgeable Joe Lavrencik personally delivered two SV racks, plus assorted accessories and options, I had already seen them at many trade shows. Still, experiencing the Sotto Voce in my own room was something of a revelation. Replacing the Goldmund racks with the CMS quite literally transformed the look of my room. Rather than being a blight, the new racks melded into the décor and showed off the components within to great effect. I took stock. Looks: check. Value: check. Ah, but would the SV rise to the sonic standard of my long-time reference rack?

Before I delve into that, let’s talk about the component that doesn’t sit on a shelf: the speaker. CMS’ solution for SV (and other) buyers is their Rize! footers ($225 each). To get a feel for what they do, I first compared the sound of my speakers with and without their normal Goldmund Cone underpinnings. Using “God Bless the Child” from the terrific OMG pressing of Blood, Sweat and Tears, I could easily detect that the Cones conferred more air to the brass, nicely tightened the bass, brought some needed control to the top, generated previously-missing depth, and gave drums both more realism and more visceral impact. Man do I love these Cones! But if I’m being honest, I must admit that they also dulled the mids a tad, and rhythms weren’t quite as razor-sharp either.

I then replaced the Goldmunds with a set of three Rize! footers under each speaker. My hope was that they would sound as good as the Cones—a tall order since nothing else ever has. To my delight, the footers delivered all the benefits of the Cones. If anything, drums, and transients in general, became even more visceral. Even better, the footers also nixed the Cones’ drawbacks; tempos regained their drive, and there was no dullness anywhere in the sonic spectrum. Then there was the wholly unexpected icing on the cake: The footers removed some of what I can only describe as “random energy” in the system. You don’t consciously hear this energy; but you can definitely hear its absence. A layer of electronic noise recedes, leaving a rare and blissful purity. Somehow, the reduction of this stray energy lets the ear-brain mechanism interpret what it is hearing as “music” rather than “sound.” That, in turn, means more realism co-joined with more relaxation.

I have gone into detail about the effect of footers in what is, after all, supposed to be a rack-system review because it turns out that the Sotto Voce has the exact same effect on everything set upon it. Bass tightens, transients gain more verve yet maintain better control, rhythms sharpen, and—perhaps most significantly—that subliminal low-level noise plummets. All this without any noticeable sonic degradation, at least not compared to my reference rack. I knew very quickly that I could live happily with the Sotto Voce. Sound: check.


But wouldn’t it also be nice if, unlike the Goldmund rack, the CMS wasn’t a closed system? Even the most content of us will revisit the upgrade situation in the wake of a lottery win, or even just a hefty bonus check. Upgrades are especially appealing (and tempting) if they can be done over time, at incremental cost, and in place. As it turns out, while the stock SV will, I believe, ably serve most audiophiles, it is only the beginning of what can be done with this system.

The first step in CMS’ multi-layered upgrade plan is an inexpensive one that doesn’t require changing anything about the SV itself. Simply insert a set of MXK-SV spikes ($225 for a set of four) between a component and its shelf. I found that the efficacy of this upgrade depends on the component being spiked. When I slid the spikes under the CH Precision D1 transport, there was a loss of transparency, spatial focus, and dynamic nuance. But then let’s remember that one of the things you get with the CH’s $40k price tag is an intricately conceived vibration-evacuation system, of which the feet are an integral part. The spikes bypass the D1’s feet, thus completely defeating CH’s elaborate scheme. In this case, it’s not surprising that the D1 preferred to be right on the SV’s shelf.

In contrast, and more typically I suspect, the Esoteric K-01 transport/player/DAC virtually breathed a sigh of relief when set atop the spikes. On its own feet, the K-01 had played the ravishingly-recorded “Title of This Song” from Beck’s recent Song Reader CD with typical élan. But compared to the same track through the D1 the Esoteric betrayed some spatial confusion, paler tonality, and a loss of clarity. With the MXK-SVs in place, though, the K-01 was suddenly doing a mighty close impression of a transport costing twice as much. The difference was that transformational. My conclusion is that for gear that has not been as fanatically engineered for mechanical grounding as CH is—which is to say, most gear—this $225 per component upgrade will be worth every penny.

The next step up is to place our friends the Rize! footers between components and SV shelves. This will cost $775 for a set of three ($600 if you buy them with the SV). I found it a rewarding upgrade. The difference is in the “purity factor”—a measure of how much random noise is being banished. The footers do a better job at this than the spikes, so the sound clarifies. I’d say the footers get you about half the way between the spikes and the next step in the upgrade path.

For a more profound—and yet again more expensive—upgrade, you can swap out stock Sotto Voce shelves for one of CMS’ “filters.” These are shaped and function like shelves, but are mechanically far more complex. The filters compatible with the SV rack are the very ones that snuggle into CMS’ high-buck systems. I tried swapping out an SV shelf for the entry-level filter, the Black Sapphire Mk.2 ($995). I was expecting this upgrade to be subtle, but, boy, was I wrong. The filter is clearly more accomplished at noise abatement, and the “purity quotient” takes a sizable jump. Under some components, like turntables, the improvement can be even more dramatic. The filter allowed bass from my ’table to really speak out, and there was a good deal more timbral information and tonal richness. These filters aren’t cheap (there are two more models above the Black Sapphire Mk.2), but they deliver the goods. Don’t listen to them if you aren’t prepared to buy them. To be exposed to what they do is to be spoiled for anything less.

The nice thing about the SV system is that if funds do not permit making an upgrade right away, it can always be done later. And when the time comes, the process couldn’t be simpler. Even installing a filter is a breeze. Heck, there aren’t even any screws involved; just lift off the SV shelf and plop down a filter. Voîlà—better sound. Also, there is no requirement to replace all the shelves at once. Instead, you can upgrade selectively, moving to spikes/footers/filters one by one, starting with the components that will benefit most. Mixing and matching shelves and filters in the same SV rack is perfectly okay.

The only gap in the SV system, to my mind, is the lack of a proper amplifier stand. Depending on the size and quantity of your amps, they may or may not fit in the SV rack. In my case, with two swank but bulky, inhumanly-heavy CH Precision A1’s, there was no way they were going on the rack. Amplifier stands to match the SV would look cohesive, but CMS offers plenty of sonically workable possibilities for outboard amps. For starters, amps that would otherwise be on the floor can be placed on Rize! footers. Alternately, an SV shelf ($125) can sit atop a set of MXK spikes, resulting in an apparition of the shelf hovering just above the carpet or floor. The shelf can also be set atop footers. The ultimate option, sonically, is to use one of the amplifier stands CMS offers as part of their higher lines. They won’t match the rack, though.

I was able to test the latter scenario thanks to Joe having provided a pair of QXK amp stands ($1995 each) with the mid-tier Black Platinum Mk.2 filters ($1895 each). Compared to the previous Goldmund amp stands, the QXK imparts that same wonderful feeling of the electronics getting out of the way, letting more music shine through. They also make the amps more coherent, with more air, more dynamics, and more bass, yet with more control of spurious elements. The SV shelves on spikes, however, are impressive as well. They give up little—just a smidge—in the by now familiar “purity factor.”

I realize that this has been a highly deconstructive analysis, so it’s important to sum up by saying that the Sotto Voce not only looks good and is more than fairly priced; it just plain works. My system has never sounded better. The hallmark of the SV rack, in all of its various permutations, is that it gets the crap out of the sound, delivering a less electronic, less hurried, less blurred presentation of the music.


Critical Mass Systems
69 Windsor Dr.
Oak Brook, IL 60523
Tel: (630) 640.3814

Price: $4500 for a four-tier, four-shelf system ($5500 in black)

By Alan Taffel

I can thank my parents for introducing me to both good music and good sound at an early age. Their extensive classical music collection, played through an enviable system, continually filled our house. When I was two, my parents gave me one of those all-in-one changers, which I played to death.

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