Graphene Sluggo - Unlocking Sonic Scenery


Henceforth to be abbreviated as "g-slug", the Graphene Sluggo from Vera-Fi Audio is getting its own review from me because a few sentences in existing discussions won’t satisfy my desire to fully share my thoughts about these. I feel ready to write, as the last two g-slugs I bought have about 20 hours on them, and the initial four have about 50-60 hours on them. I feel confident enough now to expound. These g-slugs are fascinating creatures; they are not your friendly neighborhood slugs.


For info on the prerequisite purchase needed to use g-slugs, see my review of the companion product, the Swiss Digital Fuse Box (HERE). (There’s an option to choose a g-slug for an upcharge on any SDFB purchase, and currently, SDFB owners get a 20% discount for upgrading.) If you don’t know what a SDFB is, my review was pretty in-depth and should give you most of the info you’d require. I’m a bonafide slug connoisseur with 13 slugs in my digital music streaming system. Yes, THIRTEEN, and soon to be fourteen when a new component arrives! Some devices have more than one slug, and I have them in subwoofers, external power supplies, everything I can manage because sonically it affects each device. Slugs replace fuses in your components’ fuse holders and SDFB is a non-sacrificial overcurrent protection device installed upstream from the fuse holder inline with alternating current. The SDFB is the key to slug town.


I’ll start at the end by getting to the point now, then walk through some details and my recommendations. G-slugs are better than other slugs. They are solid copper cylinders the size of standard fuses that have vacuum deposited graphene on the surface -- and its a thick, solid matte black coating with no etchings on the surface.


If you just want the gist, g-slugs make any device with a fuse holder (and a SDFB upstream) produce more linear, extended frequency response that constructs a soundstage and its sonic images with greater precision and dimensionality than you currently experience surprise. They bring you one step closer to 3-dimensional life-like music reproduction and help vanquish speaker locations, perceived room boundaries, and obstacles to musical immersion... your worst enemies!


Okay, first thought: Solid copper slugs sound better than fuses and reduce resistance between fuse holder endpoints drastically... to almost zero, right? Is that all that matters? If that were so, then everyone would use humongous 6 awg copper conductors for all cables to get really low resistance. The reality is that there are many other aspects of the power conduction chain, like dielectric properties, crystal barriers, and a bunch of other properties of various materials, their shapes and surfaces, construction geometries, etc, that result in various sonic consequences. Most of the slugs I had been using were solid copper and I chose to hand-sand and polish the surfaces to a mirror finish and clean them carefully in order to extract the finest high-frequency details (yes, this is effective in resolving systems), which is related to the well-known "skin effect" of conductors. Yet, a graphene-coated surface dramatically outperforms my best attempts at solid copper slug surface modifications.

 

To get the point across, here’s a hypothetical numerical rating scale of 1-10 with my best estimates to compare sonics of the different options I’ve tried inside fuse holders:

If a stock fuse with a tiny resistive wire is a 1 and sounds the worst, then:

  • a custom fuse with crystals, high voltage treatments, etc, is a 2 or maybe 3,
  • brass slug is a 4,
  • copper slug with original machining surface ridges and an engravings is a 5,
  • copper slug with a mirror-finshed polished surface is a 6,
  • g-slug is a straight 10.

 

Before g-slugs, my whole system was filled with mirror-finish copper slugs, which are all much better sounding than fuses, except my subwoofer amps, which have gold-plated copper slugs. Here’s what I experienced...

 

Firstly, two large sized g-slugs went into the amp. WHOA. When you first install these, it’s very energetic feeling like you are very close to the performance stage due to the inrush of newfound detail retrieval and emphasis on mids and low treble. I have experience using the top capacitors from Duelund, Jupiter, and V-Cap, and this initial experience is similar to using V-Cap CuTF caps by themselves. It’s like viewing the soundstage with a fish-eye magnifiying glass, which is interesting and highly resolving of details within that particular viewpoint, but it isn’t natural or a linear response. The copper in the slugs gives it the appropriately warm midrange similar to the copper in the CuTF caps, and the graphene enhances the top end. But, I found that g-slugs require about 4-6 hours of burn-in to relax, open up, and evenly express resolution across the audible frequency range and up into the very high frequencies, beyond what your components normally output.


In comparison, the best combination of linear and extended frequency expression that I’ve found in the world of capacitors is the relatively new Jupiter COMET silver foil. Using these by themselves or as a bypass cap in combination with the top V-cap or Duelund caps can be stunningly gorgeous, detailed, and realistic. Yet, they still can’t quite transform the listening experience like what the graphene coating on a g-slug does, which is like uncorking latent resolution and frequency extention, particularly beyond 10-12khz for exceptional spatiousness and realism. It brings out more spatial information that informs your mind of the implied locations of sounds within the soundstage. It also gives you more complex sonic textures, more defined images, and a more even and filled-out sonic picture.


When I was doing testing recently, I took all of the g-slugs out and went back to all polished copper slugs in non-subwoofer components. There was still a lot of details with the copper slugs, but immediately I noticed that the the sound stage flattened out in depth and my speaker locations were revealed with the particular recording I was listening to. I had forgotten how non-existent the speakers had become within the room when the g-slugs were installed. The front wall of my listening room had also previously disappeared, but now seemed to be a containment boundary. There was a loss of space/air in all directions with an obvious roll-off in high frequencies and the sound quality took on a quality that I can only describe as "stylized", as opposed to what was previously effortlessly natural. This is hard to describe, but it was like a more artificial sound quality, and the experience was more like listening to a recording of music or the reflection of a live performance off of a wall instead of a live performance itself. It was no longer a natural, linear frequency response, so the perceived realism suffered. Admittedly, I was a little shocked that I had forgetten how I had previously experienced music in the same room only a couple weeks prior.


I began progressively adding back the g-slugs to my components, and what unfolded with each successive addition were greater overall resolution, more evident spatial relationships and image location stability, a sense of space and transparency, and also a feeling of immersion into the musical experience and my satisfaction with it. These g-slugs have some real magic about them, and that’s why I’m writing this. Lastly, I think the contrast between silence and sonic substance widens, so it *seems* like there’s a "blacker background" from which the sounds arise from, but I think it’s actually about your components simply producing more sonic information to build a more convincing sonic scene than it is about removing interfering low-level noise. I think there’s something about the super-conductivity of the thick graphene coating that is more than a noise-filtering application.

 

In order of highest to lowest impact in components I installed g-slugs in:
1) upgrading from polished copper slugs to g-slugs in the amp had the largest effect, then
2) DAC
3) preamp, tied with the streamer’s external power supply
4) Farad Super3 linear power supplies for modem and Fidelizer router separates. Effect here was minimal, so I’m using the copper slugs in them.

 

My recommendation is to put a g-slug(s) in your amp. If you don’t like it, ummm, I would be shocked. If you have a DAC, do that too. I think a good goal would be to make approx 50% of your slugs g-slugs, and use slugs with a very smooth polished or plated surface in your other components. If you put g-slugs in ALL of your components that use IEC fuses, then you may end up with a need to balance tonality because of the additional top end energy, but for me, that’s not a problem because I have 101 ways to accomplish that balancing act, from power cable connectors, to which components they are powering, to capacitor combos connected to ground planes, to modifying acoustical treatments, etc. In other words, the things that you previously used to boost high frequencies may become obsolete. Overall, tonality of the g-slugs is really excellent and I'm using a lot of g-slugs to gain all the extra resolution I can. They extend all the way in both directions, and give you meat and bones and body... and the beauty of the finest airy details, too.


I feel justified in my enthusiasm about g-slugs after they’ve burned in for awhile. They are transformative in a way that is similar to going from a stock fuse to a SDFB with a copper slug. If you want a higher resolution sound system, g-slugs. If you go from a stock fuse and zero SDFB’s in your system straight to a SDFB and a g-slug on your amp(s), please leave your comments here for me to read! :)

gladmo

Showing 34 responses by gladmo

@roxy54 All good! I’m just here to share and discuss. Not possible to prove anything without hearing it, nor is my intention to convince people. The hallucinogenic type of instrument realness and presence is only experientially believable in my listening room, of which the graphene sluggos play a part of the whole system.

For the serious audio tweak people, when I was changing from graphene slugs to copper and back, I took care to maintain the original directionality of the slugs in the fuse holders. Otherwise, I would have waited a number of hours for burn-in and settling to occur, in case the direction of current flow might have been reversed.

Larry, did you read everything I wrote? You might have missed some of the points I made.

1) In the beginning of paragraph 2, I said "For info on the prerequisite purchase needed to use g-slugs..." and "Slugs replace fuses in your components’ fuse holders and SDFB is a non-sacrificial overcurrent protection device installed upstream from the fuse holder inline with alternating current. The SDFB is the key to slug town."

2) Bypassing the fuse holder is just your theory. The reason for the better sound is the *addition* of graphene near the end of your AC power chain, plus a thick chunk of copper. That’s what makes it unique. Bypassing a fuse holder with normal wire is not the same.

For anyone that skipped paragraph 2 or didn't understand it's meaning, the gist is that you must have a SDFB installed, as per the company's instructions, as overcurrent protection in order to remove the main fuse from a component and use a slug in its place.

Hi roxy54,

Even Einstein doubted the probabilistic nature of quantum mechanical theory, so I understand your position. I'm more of a listen and decide guy than a theorist.

@gita Yes! Definitely improved timbre. To me that falls under a combination of two things I did mention, tonality and textures. And I was telling a friend about much improved low SPL listening a few days ago due to the g-slugs, and I intended to mention it here but forgot. So thanks 🫡

@tksteingraber I think you should go for the g-slug. The return policy is great, but you won’t be returning it. At least not your first one or two.

One thing I recommend is handling any graphene product with nitrile gloves, and the bonus is that no skin oils get on the g-slug surface.

@highstream Hi, I can see how you’d think that because I previously used quite a lot of NPS-Q45T, but I stopped using it over a year ago and removed it from my cables to get a more natural sound. I can tell you with certainty that it is not the same. To me, it is very much like a limited range EQ tweak boosting certain higher frequencies. G-slugs are like using a totally different component that outputs greater resolution, linearity, extension, and vividly 3D stereo imaging. Also, my hearing is good into the teens, yes.

I haven't used VeraFi's rhodium plated slug, but it's interesting to me. I'm a big user of rhodium plated AC and signal cable connectors. I've used hollow silver slugs, but it didn't quite work out for me... same with brass. There's someone on this forum that's into solid titanium, molybdenum, and tungsten, and says they all have their intriguing aspects. I'm listening to my system right now and have no desire to look for other slugs, but I'm open if they aren't too difficult to acquire.

@larryi Since this isn’t a scientific paper about special material electrical properties seeking peer review and publication, the precise answer to your question is that there is no claim being made about the Graphene Sluggo product. It’s just a hifi audio tweak. My post wasn’t a claim as such either, but a sharing of empirical evidence with audiophile languaging on its intended application.

If I were to play around with wild theoretical guesses, I would say that the sonic effects could have something to do with some sort of super-state of electrical excitation due to having so much contiguous graphene particulate matter, which would suggest that it is in a different class compared to the way metal conductors behave in HiFi system power delivery. That’s my intuitive speculation based on zero research. And that’s what the sonic effect sounds like to me.

The closer to your component, the more significant are the qualities of the power chain, and the fuse holder position is very close so the sonic influence is very high. Putting one of these g-slugs very far away from the component, such as at the neighborhood transformer, wouldn’t be audibly detectable.

@highstream Good question. I wrote "appropriately warm" in the section about the pre-burn-in period, but actually it was overly warm for my system when I first installed them in my amp. That there is a copper core was obvious to me. It's hard to describe that initial experience because warm usually implies a darkened top end, but that's not what it was. It was both warm and with a lively top end at once. Anyway, I think you are really asking about tonality after burn-in. As a tonality aficionado, I maintain that it is very good overall. They have some natural warmth, but overall they are more neutral and extended. To me, freq extension, both low and high, is a key to the best overall tonality, and can be one of the more difficult aspects of great tonality to achieve. G-slugs help your components make that happen. Bass, mids, highs all have the qualities of realistic and precise presentation.

The advantage of getting a SDFB is that you can remove the main fuse. But you need to replace it with something, either by inserting a slug or doing surgery on your component and bypassing the fuse holder with wire. Most people go with a slug. My experience is that g-slugs are the best sounding slugs, by far.

There are multiple sellers of graphene of various flake sizes. VeraFi bought some and attached it to copper cylinders using vacuum deposition.

https://en.m.wikipedia.org/wiki/Vacuum_deposition

 

@highstream You're welcome. I agree about arrogance and smugness around here. There's a craving for the feeling of being right about some concept and making others wrong, even if it's mostly just based on prejudice.

If you can use a very short adapter instead of a shorty AC cable, NEMA 5-15P to IEC C13 adapters are nearly invisible, sonically speaking, and very inexpensive.

By the way, Mark from VeraFi did not compensate me to write this review. I wrote it out of pure appreciation and gladness about enjoying my sound system.

I have a bunch of SDFB’s. Your choice of "shorty" power cable that goes from the outlet to the SDFB matters, but somewhat less sonically than the power cable that goes from the SDFB to your component. VeraFi offers a couple different pre-built options for this. I do a lot of DIY component mods and cable builds, so I built my own shorties for my components to match my preferences for AC cabling and connectors. For my subwoofers, I needed longer shorties so I ordered cheaper, larger gauge AC cables from Amazon.

@emergingsoul You’re not replacing an circuit breaker, if that’s what you mean. You are just adding a device inline between your component and the AC outlet it plugs into, and replacing a fuse with a slug of the same size. For more info, you can see my review of the Swiss Digital Fuse Box for an explanation (linked near the beginning of this review), or the walkthrough video on Vera-Fi Audio’s product page for the SDFB, near the bottom.

None of you guys have tried this product, yet you strut around with chest puffed out, looking for the pleasure of flinging snide insults on the internet. Take a look at yourselves before you comment on my review again.

@larryi

I'm looking forward to your impressions of the graphene sluggo vs. bypassing a fuse holder with wire. Please share here what you find.

For example, my preamp has 4 fuses in total, and gets a big upgrade with a sluggo in the fuse holder by the IEC while leaving the downstream fuses installed. My DAC requires two main AC fuses at two different different ratings, so I use a SDFB set at the lower rating with both fuses replaced by sluggos.

@pickindoug Many people use SDFB on devices that have more fuses downstream from the main AC fuse with excellent results by only replacing the main AC fuse(s) with sluggos. I can attest to this. Maybe someone else will chime in about it too.

The equally sarcastic but opposite position is never roll anything. Now you have the two extremes. Audiophiles live somewhere in the middle and expert audio product designers live closer to the roll everything extreme.

I think all of my g-slugs are fully burned in now. I did a recording with the cheapest measurement mic and recording interface from Behringer, so don't expect wounderous quality and a low noise floor:

graphene sluggos in my system

Thanks Mark @verafiaudio ! I’ve been trying to figure out how to make these system recordings not sound muddy and atrocious. I don’t think there’s much I can do with a $35 mic and the cheapest of cables and components feeding my laptop... But think I’ve optimized levels more now than before, and it’s a bit less crappy now...

sotho blue

This is fun :)

I know that nobody else can hear the graphene slugs in that recording, but I can. Assists in helping it sound very much like the real thing

@tdhayes I don't know. the Rythmik sub isn't very sensitive to different sluggos like it is when going from a fuse to a sluggo.