Atlas Cables Grun Coherent Earthing System | REVIEW

atlas cables grun eos block

The Grun Earthing System from Atlas Cables is the third product I’ve reviewed in the last year that addresses grounding in your high-end audio system. The first two products, of course, were the Nordost QKORE system and the AudioQuest GroundGoody grounding cables.

The QKORE was an expensive, all-out assault on grounding that used heavy, compact hubs and a series of optimized ground wires to achieve a solid “artificial earth,” and it worked incredibly well—so much so that my listening room started to resemble an anechoic chamber. (The Nordost QKORE was assisted, in this instance, by an AudioQuest Niagara 3000 power conditioning and all sorts of NCF products from Furutech, but nevertheless the effect was spooky and also revelatory.)

The second grounding product came from AudioQuest. The GroundGoody Jupiter and Saturn grounding wires were simple and relatively easy to install. While both the $30 Saturn and the $300 Jupiter effectively reduced ground hum, which is the bare minimum task that a grounding/earthing product should accomplish, these directional wires were designed to drain RF noise and distortion away from the phono cartridge. That led to greater clarity and sharper transient edges and a permanent place in my analog rig.

The Grun Earthing System from Atlas Cables occupies the territory in between—it’s potentially complex like the QKORE, with countless combinations possible, but it’s not quite as expensive. It’s more of a complete solution for your entire system, one that combines an earthing system with cabling. Instead of those big, heavy grounding hubs the QKORE system uses, Atlas Cables uses a power strip, called the EOS, that contains the distribution block—the “artificial” earth you’ll need if you aren’t creating an ufer ground in the crawlspace of your home. Then, instead of hooking up ground wires to every component in your system, those grounding wires become part of the cabling.

That’s where the Mavros cables from Atlas Cables come in. These are premium interconnects and speaker cables that have sort of a second connection point for the ground cables throw flying connectors near the terminations. Aesthetically this is interesting, because those ground wire leads don’t look like ground wires—they have the same green jackets as the Mavros cables, and they are hooked up with connectors and leads that makes it seem like some new three-conductor system, one slightly more complex and versatile than the typical phono cable but similar in a very basic way.

mavros cables for the grun coherent earthing system

Atlas Cables

I’ve never heard of Atlas Cables before Anthony Chiarella of Vana Ltd. wanted me to take a listen. Once I did a little research on Atlas Cables, I found that we weren’t talking about another loom of inexpensive wires that sound really good for the money. No, these Atlas Cables, in conjunction with the Grun Coherent Earthing System, are part of a very serious approach that involved your entire audio system. (I’m sure this applies to your video systems as well, since the people of Atlas Cables started in that side of the industry.)

Atlas Cables is based in the UK, in Kilmarnock, Scotland. With a couple of exceptions, as the website states, all their products are designed, tested and built there—by Atlas engineers. As Roy Feldstein of Vana explained, “Although Atlas has been producing critically acclaimed cables for two decades and has built a cult following overseas, many people in the States haven’t heard of them yet.”  

My giant box of Atlas Cables included a pair of Mavros Grun speaker cables ($2995), several pairs of Mavros RCA interconnects ($1400 each), and some of the EOS Superior power cables ($1680 each). The EOS itself is $1000, and you can order whatever combination of filtered and unfiltered outlets that you need. Once you’ve made those choices, you can determine if you need additional mains power adapters, RCA adapters and various grounding leads—most of these retail for less than $200 each. You can also buy all sorts of connectors and adapters that allow you to ground through RCA, XLR and other types of digital jacks. The box contained a little of everything so I could experiment with different systems.

Roy elaborated on this further:

“Interconnects and speaker cables from Atlas’ reference families (Mavros and Asimi) come configured with Grun by default. Adaptors for connection to chassis or signal ground are included with the single-ended interconnects and speaker cables. Grun is available as an optional addition on some of the intermediate lines as well.

The spade lug adaptor can be used on any standard grounding post or the Eos power block, but we don’t want to give the false impression that the Eos system is a necessary investment to benefit from Grun. There are 4 options. The spade lug or RCA adaptors are included in the box with the speaker cables and single-ended interconnects. Besides the Eos, the Nema power adaptor lets you ground to any spare outlet (they can be configured to accept as many as 4 or 5 Grun leads, so this is an efficient option for a Mavros-heavy system). The attached pictures show each configuration. The Eos and Nema adaptor provide an equal level of performance.”

If I was going to purchase the Atlas Cables Grun Coherent Earthing System and Mavros cables for my reference system, I’d probably wind up on one EOS, one pair of speaker cables, three sets of RCA interconnects and one pair of XLRs, four or five of the Superior power cords, and all the accessories and leads—we’re talking around $12 to $15,000 for the full Grun. That approaches the cost of the QKORE, all three units, with assorted ground wires. But with the Atlas Cables Grun approach, you also get cables. And a power strip. Move up and down the Atlas Cables line and you can more or less adjust the total cost for your budget and choose the compromises that are important to you.

That means, of course, that you can go nuts and drop a lot of money on the Atlas Cables Grun Coherent Earthing System if you so desire. You don’t have to, though—there are some very basic configurations as well.

atlas cables eos

I Am Grun

Atlas Cables approaches grounding in the same way as Nordost and AudioQuest, as a way to combat new issues due to wireless technologies. As I discovered with the GroundGoody, it’s not a matter of ground hum or even the overall level of the noise floor and whether or not it’s audible from the listening position, but what reduced noise and distortion can add to your system’s performance and its ability to let the music through unfettered.

The Atlas approach to an independent earth addresses an important point, that we tend not to notice this RF noise pollution until it is removed. As Atlas explains:

“Ironically, this is generally only noticeable when eliminated – even though much of this ‘noise’ is theoretically at frequencies beyond the range of our hearing. The main sources are noise in the mains supply and component ground connections – mobile phones, ‘wall wart’ chargers and wifi networks are major offenders – while a percentage is actually generated within the equipment itself. Generally things have got worse with the advent of computer audio. The Grun Coherent Earthing System addresses these issues by providing an ‘independent’ earth for users of Mavros and Asimi Ultra interconnects and Mavros speaker cables* with the new Grun configuration.”

eos with eos superior power cables

Atlas Cables Set-Up

Hooking up your system with Atlas Cables Mavros cables and the Grun earthing system requires some patience and planning. First of all, you hook up the cables. It’s no different than inserting any loom from any brand, but you’ll want to pay special attention to routing and dressing your cables because it’s about to get a little more complicated. You’ll need to find a spot for the EOS power strip—not difficult, but it’s better to keep things relatively close. You’ll have more options, which will be important when you’re up to your elbows in wires.

Finally, you’ll need to start making your grounding connections throughout the system via the flying earth connectors near the end of the cable. (The most basic connection for RCA interconnects, for example, is to plug the cables into the inputs, connect the two flying grounds to a Y-shaped lead, and then plug that into an empty input.) Atlas Cables gives you plenty of choices when it comes to the cable configurations—some of the grounding wires are long, some have more than a single run and some have different types of connectors.

At some point, the EOS will have a single ground lead running from its lug to either another lug elsewhere in the system, or you can add RCA adapters and find a spare input.

As you start moving through the system, it starts becoming easy to know which grounding cable from the Grun system goes where. Plus, the instruction manual is very helpful when it comes to getting everything in the right spot. (There’s more than one way to do this, obviously, depending upon the specific needs of your hi-fi system.) It’s possible, I suppose, to make a wrong connection somewhere and create a brand new ground loop hum issue, but it never happened to me.

mavros and brinkmann

I had one small issue with the installing and uninstalling of these cables—most of them use a fixed connector with a finely threaded collar that requires quite a few turns until it is seated properly. That means you might be wrestling with all those wires, getting everything to stay dressed and routed. It’s much more involved when you de-install the Grun system, and one wrong turn results in a rat’s nest because it’s tough to move the connectors independently of the cable runs. You’ll be reminded of attaching garden hoses to outdoor spigots and watching that sprinkler on the other end flip round and round.

In fact, that’s the only issue I had with the Atlas Cables and the Grun. I spent eight years in telecommunications, terminating wire onto patch panels, routing cable runs neatly even when it couldn’t possibly be seen by another human. Those skills came in handy when I installed everything, and yet I was still mildly disappointed that I eventually couldn’t tame the flow of cables. You can see this in some of my other recent reviews—there’s some craziness going on behind my equipment rack in the photos. Even my Furutech NCF Boosters couldn’t quite corral the cables into the neat flowing lines I usually require. Plus, I still try to separate power cords from low voltage cabling as much as possible.

I also know plenty of audiophiles who would accept this challenge with enthusiasm. It’s not without its fun.

I had the Atlas Cables Mavros and the Grun earthing system in my system for many months—as soon as I took the Nordost QKORE out of the system—so I won’t go into a long discussion of the associated components. It remained a vital constant.

atlas cables mavros speaker cables

Results with the Grun

Let’s just say that I’m getting really used to having a completely quiet system with an astonishingly low noise floor. As I mentioned with the QKORE, my room gets so silent that I can detect some very low-level tinnitus. Whenever I heard a hum or a sizzle or anything out of the ordinary in my system, my search always led me to another room, where some sort of appliance was gently humming to itself as part of its normal operation. Fans. Air filters. The sounds of the city outside. The friggin’ neighbors doing the things that friggin’ neighbors do.

The Atlas Cables Grun system got me close to that anechoic feeling I had with the Nordost QKORE, perhaps equal. (What an impossible A/B comparison that would be.) My first test, leaning my ear up to the speakers as I turned up the volume (with no music playing, of course), yielded the same uncanny feeling of complete silence, as if something in my system still needed to be switched on.

In fact, I even noticed that my components were much quieter when I simply plugged them into the EOS power strip without the Mavros/Grun system engaged, with just one ground wire connection to another lug. That an excellent argument for just trying out the EOS on its own before you go down the rabbit hole. As I learned with the QKORE, things just keep sounding better as you add grounding runs—the lowering of the noise floor is obviously something that is always a matter of degree. You can keep going until you no longer have a space to sit. But you don’t have to go that far.

hyper cable loom

Atlas Cables Hyper

Anthony included a small loom of the more affordable Hyper line from Atlas Cables—two pairs of RCA interconnects ($195 each) and one pair of 3.5 speaker cables ($395/pair). This is the more basic, affordable line with polyurethane jackets, not as visually distinct as those intriguingly greenish Mavros cables. He wanted me to see the difference between the Atlas Cables than cost hundreds of dollars and the Atlas Cables that costs thousands of dollars. (The flagship Asimi Luxe line, which can also be used with the Grun system, can edge into the tens of thousands.)

The Hyper line features the new Achromatic connectors, which are low-mass, non-magnetic and cold-welded (not soldered). Atlas Cables claims these new connectors leave less of a signature to the sound due to a reduction in mass and contact resistance.

While they aren’t designed for direct use with the Grun Coherent Earthing System, the Atlas Cables Hyper runs wound up serving a few important functions during their stay. My system has become complicated over the last few months, with my digital palette expanding with the Merason DAC and the Innuos Zen Mini Mk. 3 music server, not to mention two Technics turntables facing off for some exhilarating A/B comparisons, and a plethora of phono stages. (Yes, I would say that I had a plethora.) Plus, what’s with all these external power supplies everywhere?

In other words, it seemed like I always needed just one more RCA interconnect here, or one more XLR there, and I didn’t have it. In went the Atlas Cables Hyper.

While this seems like the broadest of evaluations, the various runs of Atlas Cables Hyper were present, in one place or another, in my system over the last few months, a period that I enjoyed some of the most exquisite sound at home in a considerable amount of time. I had Qln and I had Allnic and I had Jeff Rowland Design Group and I had Brinkmann and I had Pass Labs. When I needed a pair of speaker cables with banana plugs, I never hesitated to grab the Atlas Hyper.

hyper hooked up to volti razz


Looking back on my time with the Atlas Cables Grun earthing system, I feel like I fretted about the mess behind my rack a little too much. But I’ll tell you what—if you spend this kind of money on the Grun and the Mavros and the EOS and whatever else you require, make the dealer come to your house and hook everything up and dress up all the cables for you and make everything pretty. Then take ‘em out to lunch.

That’s pretty much it. That’s the only complaint. The Atlas Cables Hyper lines were great values for the money because they functioned well as a loom and never subtracted from the overall system in a meaningful way—and this was with a number of very revealing components. The Atlas Cables Mavros cables, sans the Grun earthing system, comprised a first class cabling loom that helped to create a steadily quiet and neutral presence with all types of analog and digital systems. The Mavros cables alone could be purchased alone, and you can then upgrade with the Grun over time. I think the EOS is a great product at a great price, because it’s a high-quality power strip with excellent parts AND a distribution block that allows you to ground your system through then power cords.

Separately, these products all work. Together they are formidable. After the Nordost QKORE, AudioQuest GroundGoody and now the Atlas Cable Grun, I realize that grounding your audio system isn’t a novel or trendy thing to do, like putting Armor All on your CDs. The increase in wireless technologies and all that associated RF noise and distortion has created a new and very real problem in the audio world, and if you’re using a network streamer or specialized router or Bluetooth, then you probably need to come up with an earthing strategy for your system.

The genius of the Atlas Cables Grun Coherent Earthing System and the Mavros cables and the EOS is the integration of the system into both cables and a power strip/distribution block, items that are generally costly. The Grun system has an edge because it’s such a holistic approach, not to mention an economical one. Atlas Cables is a smart company with a lot of smart ideas, and I can’t wait to see them develop and expand these technologies into the RF-soaked future.

atlas cables grun coherent earthing system

grun grounding lead

atlas cables mavros in marc phillips system


atlas cables with furutech ncf

mavros rca interconnects

hyper speaker cables from atlas

adapters for grun coherent earthing system

1 Comment

  1. All cables, power cord, spkr cables, interconnects, ought to be suspended. Use PS Audio premier plant, for powering ur audio equipments. Earth connections must be linked. U get clear n clean sound. Yes, I believe, Nordost n Audioquest earthing system could give, clean sound. Not cheap, though.

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