Publisher Profile

Stage III Concepts A.S.P. Proteus power cable Review

By: |


Using the Electrocompaniet Nemo

This was the comparison using the system combination I’m most intimately familiar with, which both helped and hindered the comparison. I have tweaked my reference system around the Nemos and have thus achieved what to me is the “best” sound.

On the one hand, I was able to notice subtle differences, but on the other I had to fight my preconceptions about how a piece of music is supposed to sound. Over the years, as I have developed more and more specific preferences and prejudices, I find it increasingly difficult to hear significant improvements when introducing review components into my reference system. Differences certainly, but not improvements. In short, it took a bit of listening to objectively describe the differences between the two power cord combinations. Not to get ahead of myself, but I had a much easier time finding that the Proteus upped the performance of the other two amps in my comparison.

I started by playing “Annabelle” from Macy Grey’s Stripped. This is a very evocative piece of music on a very intimately recorded album. Macy sings, purrs and growls throughout, providing numerous opportunities to hear shades and nuances in her vocal presentation. Switching between the Proteus and my own setup it seemed that the differences were more preference than definitive. Through the Proteus, the performers were a tad more solid, while with my existing Lessloss setup they were a bit more ethereal. The initial round ended in a tie, with my own personal preference making the difference.

I next teed up the Red Hot Chile Peppers. I started with my own setup, which was very dynamic and projected a very live feel. I then switched to the Proteus. This time I immediately heard a difference in the presentation. The difference wasn’t gigantic, but with the Proteus, the Chilies became more vivid and more potent. The performance was conveyed with an even more “live” feel than before. Percussion and bass lines were more vivid and aggressive and really made you want to dance. Score one for the Proteus.

Next up were tracks from David Bowie’s Let’s Dance and Steve Vai’s Where the Wild Things Are. Both albums sounded just a bit better with the Proteus in play. Again, the power and solidity of the performances were a little more live sounding. Though both power connections produced great results, the Proteus was just a little more potent.

I expected Radiohead to produce similar results, and was mildly surprised when I preferred my Lessloss setup. I thought that the ethereal sound of Radiohead came across better in the less weighty presentation that was produced by the Lessloss combo. Of course, personal preference has a lot to do with this, so I suspect others might feel differently. I also had the same reaction when listening to The Head and the Heart and Nora Jones, but it was a very close call.

To summarize: I liked the Proteus powering the Nemo more when playing the Red Hot Chile Peppers, Bela Fleck, David Bowie, and Steve Vai; I liked my current setup powering the Nemo better when playing Radiohead, The Head and the Heart and Nora Jones. I was neutral in their relative performance when playing Macy Grey.


Using the Pass Laboratories Xs 300

I gotta tell you, I thought long and hard about going through the effort to include these amps in the review. Each channel of these monoblocks is a 2-box monster totaling 298 pounds. That alone would make anyone think twice. However, the bigger issue is that I normally only pull these amps out in winter because of the huge amount of heat they generate. I can literally turn the heat off in the listening room in the dead of January and feel perfectly toasty. To get additional perspective, check out my review of this amp in Dagogo back in January 2015.

I preferred the Proteus powering the Xs 300 in almost every instance, with the exception of Nora Jones and Macy Grey, where I was neutral in their relative performance. The Xs 300s convey a very powerful, dynamic and solid musical presentation while providing excellent nuance and delicacy in the mids and highs. Based on my experience with the Nemos, I anticipated my existing setup to be a tad more organic when playing Radiohead, The Head and the Heart, Macy Grey and Norah Jones, but something clicked between the Xs 300 and the Proteus. The power and solidity were easily a 10 out of 10, but the nuances and little details created an amazingly intimate listening experience. I don’t mean “for a high power amp.” I mean for any amp.

Nora Jones’ breathy voice was in front of me in the room. Correction, she was in the room. There was no stridency at all to the piano. The highest notes of course reverberated like they do in a good hall, but there was absolutely no “white noise” or “glassy” effect. The attack and decay of each note was outstanding, and key to creating the live-sounding experience. For those of you who are familiar with the difference, the Xs 300s with the Proteus were more like the detail you hear from the Bricasti Model 1 dual-mono DAC, while with my existing setup the sound was more like what you get from an MBL 1611 DAC. My own preference is for the latter. However, when it came to the bass performance, I preferred the sound of the bass in Cold, Cold Heart and Come Away With Me when the Proteus was in use. The added sense of power was clear and added to the realism of the performance.

Moving on to Bela Fleck, the nuances of the bass in every track were more audible. Each pluck and every induced growl was framed in sharp relief against the overall presentation of the bass and the other instruments. And the sense of power in the bass…well, you had to be there.

Another great example of the sense of power added when the Proteus was in play is the Red Hot Chile Peppers’ Dark Necessities. Virtually everything about this tune is explosive. When I played it using my own setup the room rocked and everyone listening was left a tad breathless. I stopped the music and changed to the Proteus. About 1 minute into the song everyone in the room looked at each other with just a hint of disbelief. Every person said that they couldn’t believe that Dark Necessities sounded even more dynamic and explosive than before.

The Proteus seemed to be an ideal fit for the Xs 300. The solidity of the images produced when the Proteus was feeding the Xs 300 was the best I’ve heard with this amp. All percussion instruments were vividly realistic with hit-you-in-the-chest intensity, but without any loss of delicacy when necessary. The upfront drums in David Bowie’s Let’s Dance were on the stage right in front of you with an almost frightening presence. Mind you, I would never have guessed that any power cord by itself could better my existing power cord/conditioner combo both in bass impact and delicacy of presentation, but there you are.


Using the Electrocompaniet Nada

The Nada is the little brother of the Nemo, but it’s not only a bit less powerful – “only” 400 wpc – but it is a bit more analytical than the Nemo, which is one of the warmest-sounding solid state amps that I’ve encountered. I wasn’t sure what to expect, but decided to start with Nora Jones and assess the effect on Jones’ breathy vocal style. The Nada had always been very detailed, but now even greater nuances surfaced when listening to Don’t Know Why. I wasn’t just hearing the breathy detail. I could “feel” the breathy detail the way I do with the Nemo. This was totally contrary to my expectation. I thought that the presentation would move from “neutral” more toward the “clinical” side when the Proteus was inserted. Instead, it went the other way.

Going on to Cold Cold Heart, the bass, as expected, was deeper, more natural and more solid than I’d heard with any other power cord powering the Nada. Not quite as warm as with the Nemo, and not quite as solid as with the Xs 300, but really pleasing, realistic-sounding and detailed in all respects.

Moving on, I teed up Bela Fleck’s title track on Flight of the Cosmic Hippo. For an instant the thought occurred to me that I had left the Proteus plugged into the Xs 300s, which of course was ridiculous since I had already played music through the Nada. The lowest bass notes of this track now sounded like they came from a totally different amp. They were not only fast and deep, but the leading edge and ultimate decay of each bass note were clearly audible, thus imparting a much more organic sound. The growl of the bass was now a you-are-there experience, not just a nuance in a recording.

These effects were clearly replicated when playing the Red Hot Chile Peppers, Radiohead and David Bowie. In fact, I discovered that I preferred the Nada powered by the Proteus in virtually every instance.

Similarly to the effect it had when used with the Xs 300, the Proteus made everything a bit bigger, more realistic and more powerful when the music demanded it. However, it also imparted the Nada with another quality. Paradoxically, it made the Nada sound less analytical. I had guessed that the opposite would occur, that the Proteus would make the Nada sound even more analytical. That was not the case. When used with the Nada, the Proteus clearly acted like what was, for me, a component upgrade.


Let’s start with an obvious conclusion, one that doesn’t require auditioning the Stage III Proteus: this is one expensive power cord! When talking about this kind of money you have to think of the Proteus as a component, not “just” a power cord. When you audition a new high end component you are typically either looking for the proverbial “final link” that gives your system that last bit of perfection, or in the case of power cords, you want it to significantly improve the performance of the component it’s feeding. In the best of all possible worlds, you get both.

The Proteus is an absolutely first-class, state-of-the-art power cord that is extremely dynamic, robust and nuanced. With the exception of the Electrocompaniet Nemo monoblocks, it made every amp I tried it with seem “upgraded.” If you are looking for the best without regard to price, you have to include this power cord in any short list of power cords for amplifiers. Even if you would normally never even look at power cords this expensive, there are two things I suggest you consider.

First, the Stage III Proteus appears to make most amps sound more potent and robust. I can’t say exactly why, but both the Electrocompaniet Nada monoblocks and the Pass Labs Xs 300 quad-chassis monoblocks benefitted the most from inserting the Proteus. The Nada especially benefitted, taking on a more robust, powerful and solid sound. The Pass Labs Xs 300 monos were already very robust amps, but substituting the Proteus made the already-robust sound more nuanced and less clinical. To be clear, the Xs 300 amps are not clinical but are very “neutral”; the Proteus moved them a tad toward a warmer sound. I have no idea why the effect was less on my Electrocompaniet Nemo monoblocks, other than that I’ve tweaked the sound around the Nemos and not the other two amps.

Second, the more “ordinary” your home electrical system is, the more the Proteus will improve the sound of the components being fed by that electrical system. Now, I am not saying that it’s a substitute for a good dedicated electrical system for your audio. The Proteus easily sounded the best in my Reference Setup. However, more than any other power cord I’ve tested, the Proteus seems to make the last meter or two of power –or, from the perspective of the component, the first meter or two (more on that another time) – matter more than other power cords I’m familiar with. The Proteus was excellent being fed by every circuit I tested it on, but it made the least difference when fed from my dedicated 8-gauge circuits. Surprisingly, it made more difference when used in circuits employing special noise-rejecting audiophile 10-gauge cable. Finally, it really made a difference when I used the Proteus with electrical circuits that were ordinary 12- and 14-gauge standard home wiring.

The point is, you definitely need to treat the Proteus as a major component and/or electrical system upgrade, and not just think of it as another power cord tweak. I wish I could have tested a single Proteus on a high power integrated amp to see how much it would benefit such a component. In some systems that could provide more bang for the buck than going to separates.

Earlier I referred to the Stage III Proteus power cords as “monsters,” like their siblings the Leviathan and Kraken. I’ve come to the conclusion that maybe an even better characterization would be “Monster Tamers,” given how they brought out the best in several monster amps. After all, other than Poseidon himself, the Greek Proteus was able to tame and control various giant sea creatures, and the Proteus can certainly tame and get the best out of your amps. Very highly recommended, if you can afford them (and, I guess, even if you can’t).


Copy editor: Dan Rubin

7 Responses to Stage III Concepts A.S.P. Proteus power cable Review

  1. Mike Johnson says:

    I am puzzled, but interested in the improvement you speak of with the Pass Labs Amps. I have been told by Pass Labs that aftermarket power cords make no difference in their amps, due to their design. Other Pass owners have also stated they heard no difference in upgrading power cords on their Pass amps. You do not agree with this recommendation ?

  2. Ed Momkus says:

    Hi Mike – I’m familiar with the fact that Pass states that PCs don’t make a difference with their amps. Though that has generally been my experience with tonality, speed, attack, decay and most other Pass amp characteristics, on a few occasions I have heard very subtle changes in soundstage width with some PCs I’ve tried on Pass amps.

    Quite frankly, I was at a loss to explain my experience with the Proteus on my “big” amps. That is why I felt I had to be very specific about the effects with each amp playong different types of music. The results did not match my original expectations (prejudices?). Furthermore, I don’t know whether the results would have been different if different Pass Labs amps were involved.

    The only other thing I can say is that the differences, though clear to me, were still subtle. I know there are many people (normal non-audiophiles) that would not acknowledge any difference, and probably a good number of audiophiles who say the differences were too subtle and subjective to be reliable.


  3. Bill says:

    The improvements you heard are similar to a review of the Siltech Ruby Hill, by another reviewer. Both have in common, heavy silver alloy conductors. I find it interesting, but 18K is not my budget range for components.

  4. Tim says:

    Your kidding ….right ?
    Earth to audio…earth to audio…
    Jeez : )

  5. phil says:

    More that a amp, preamp and speakers and this is a power cord. This is what is killing our hobby and reviewers go along with this farce and promote it.

  6. Tom says:

    No power cord would be found superior to another in a blind test. The fact that sighted tests reveals differences is a great example of the confirmation bias in full display. Even with the obvious differences present in speakers, Harmon labs has shown differences in preference in sighted testing versus blind testing. How could a power cord somehow overcome hundreds of feet of 12 gauge solid copper house wire? Wow…

    • Dear Tom,

      Thank your for your readership and comment. I’m not sure I understand you: You are visiting a web magazine purveying the use of audiophile-grade products. You have no need to convince me or our staff, for we know what we hear.

      Instead, I encourage you to invest in just one premium power cable and use it for a month. Then, replace it with your generic power cord. See if you don’t miss the performance of your system with the premium power cable.

      I look forward to hearing from you again.

      Constantine Soo

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Popups Powered By :