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 . 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! :)
Assuming you are willing to take the risk of running your gear without a fuse, why use an expensive slug when you can re-wire and bypass the fuse holder entirely with a straight piece of wire? A slug would only make sense if you have plugged the component into a digital fusebox that will sense powerline anomalies and open a relay to protect the gear. If you are foregoing the digital fusebox, you should also forego the fuse holder and slug.
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 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.
Okay, the slug may be a positive "addition" to the circuit that improves the sound in your system, but, what it is doing to the sound can still be best ascertained by seeing how the addition compares with a bypass of the fuse holder entirely. Otherwise, the comparison is basically between other "additions."
I don't have any objection to the concept of an addition to a circuit having a positive effect; but, anything that alters the sound has the possibility of altering the sound in the wrong way for a particular system or a particular listener's taste, so I would like to know what improvements you hear over no fuse holder and slug of any kind.
Also, which component benefits the most from a digital fusebox? Will it's effects be obvious with just one component or will several be needed to hear what it does?
@gladmo, you didn't make it explicitly clear that the Swiss Digital Fuse Box provides the protection to replace the fuse.
Even when you bend over backwards and explain it 3 times, there are people who still think you're running without protection. I think you have to just accept that you'll never make everyone understand.
Your recommendation to try the graphene slug in an amp first and then a DAC, is this with or without the digital fusebox for purposes of a brief demonstration?
I've only heard a brief demonstration of fuse vs. no fuse (copper slug), and I did not hear any difference. Is the big difference from the use of graphene as the slug vs. going without a fuse and using a digital fusebox? If it is the slug itself, that would be a cheap experiment vs. having to get a digital fusebox.
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.
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.
The biggest resistance in the circuit is the $2.49 cent fuse clips that the sluggo goes into. so bypassing the fuse clips with a quality conductor would probably be a good thing.
I read your thoughts on "resistance isn’t the only factor" and I don’t feel very enthusiastic about your argument. I think resistance (or impedance), especially at higher current loads, is the overriding factor. Graphene is used because it is a superior conductor.
I did test the SDFB against no fuse at all and found no fuse at all slightly better but the SDFB greatly superior to any fuse, including the expensive ones.
Thank you for clarifying that none of your trials and comparisons were made without the digital fusebox in the circuit. This means power going through one additional three prong plug, additional wiring of the digital fusebox, additional relay contacts in the digital fusebox and a female outlet before we get to the graphene plug. I am not saying that this invalidates results, but, it adds additional variables to the assessment of the graphene plugs themselves.
In being open minded about the impact of the graphene plugs, I am willing to do a short-term trial of just the plug (foregoing protection of a fuse) because the cost is not that high. I cannot recall the last time I blew a fuse, so this would be a fairly low-risk experiment.
When your components-sans fuses catch fire and burn down your house you will be crying!
The Swiss Digital Fuse Box seems to be pretty reliable, based on the users who post here. It’s basically a circuit breaker, the way I understand it, so it should be able to provide the same protection as a fuse. Do you have reason to believe otherwise?
(I realize I’ve oversimplified my description of the SDFB, but it seems important to clarify that its use isn’t forsaking protection.)
Thank you for the wonderful review of our Graphene Sluggo. I feel as you do - for me, they changed the game entirely
@cleeds - to date SDFB has about 750 systems installed with one return that might have been a fault other than our own. As well, better than 70% of our SDFB End Users have bought multiples.
It's a combination of MicroP Controlled software that must be installed at time of purchase with a pretty sophisticated Hall Effect Sensor and Relay
Normal State of Operation is OPEN STATE until the above system senses all is well and allows current to flow. We have SAVED many systems already as reported by our Customers.
Current SDFB works up to 12 amps, but Fuse Box Max ships at mid week (after a long wait) with rating to 32 amps - they both work flawlessly.
If you have questions - feel free to e-mail at verafiaudio@gmail.com
Thanks for keeping us up to date with your findings. I’ve been following your informative epic with great interest. I’ve had good luck with aftermarket fuses, but the SDFB clearly in another league.
When I bought the SDFB, I went straight for the g-slug. Generally my results, as far as they go, mirror your own. I will add that if you’ve only got 50 or 60 hours on the g-slug, you may not be completely cooked.
I’m surprised I haven’t read anywhere about improved timbre. I guess it’s system dependent, but to me it’s pretty striking how instruments sound more like themselves now. Also, low level listening has become more satisfying.
"Tonality" may not be the word I’m looking for, but the presentation has certainly changed. I had configured the peripherals of my system around a tubed integrated amp. I swapped in a solid state integrated a couple of months ago. My cables are all from a well regarded manufacturer. They’re known for their open, fast character. Well, I’ve just ordered a power cord reputed to be "organic" and "relaxed." I’ll see where that takes me. It may be more harmonious with the g-slug loaded SDFB.
@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 🫡
@gladmo Thanks for the exhaustive review. I suggest a comparison of the graphene sluggo with either NPS-1200 contact enhancer or the current version, NPS-Q45T, both of which contain graphene. The nature and quality of the gains you describe are similar to what those provide, both immediately and after three days. Btw, since I don’t know anything about you, is your hearing really able in the 10-12K range (vs. diminished capacity or merely sensing a high end there, like many of us only have remaining)?
@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.
Thanks for the detailed review Gladmo- Have you or anyone else compared any other Sluggo types besides polished copper and graphene? Silver solid, Silver hollow, rhodium/copper, gold/copper, rhodium/silver hollow or solid? Lots of choices out there now. I have been on the fence with the graphene sluggo and use solid silver, gold/ copper and rhodium/silver hollow with good results.
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.
Got a pair of SDFB's and used some "hardware store" copper tubing with them. A remarkable improvement from the Hi-Fi fuses that were in the monoblocks. Then installed the Super Sluggos and in my opinion the copper tubing and the super sluggos were quite close to each other. I then went to 99.99% copper OFHC copper tubing that I polished and again noticed another improvement although not quite as much as the initial improvement with the SDFB's and copper tube/sluggos gave initially, but an immediate improvement in the sound stage yet again.
IMO I feel the the skin effect provided by using tubing performs better than a solid piece, at least that is what my ears are telling me!
I am waiting for the air core/hollow graphene Sluggos to arrive. Should be a worthwhile wait as far as I'm concerned. Lovin the improvements the SDFB's allow one to experiment with.
What utter rubbish, the best example of fairy dust and use of the placebo syndrome yet. People can’t be that stupid, my suggestion don’t quit your day job. 200 years ago you’d be going around the country in a Horse drawn caravan belching Sluggo elixir.
@gladmo You wrote: “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.”
Does the graphene sluggo maintain that? You wrote about balancing, something I pay attention to too, while seem to be more adept at developing options than probably most of us.
Thanks for replying about NPS-Q45T. I didn’t know that you had previously used it. Unlike the NPS-1260, my bottle of which inexplicably disappeared, I found that the Q45T, at least on tube prongs, changed the tonality to neutral, so took it off.
Interesting post. Well articulated deep dives into our hobby are always appreciated.
I was one of those "doubters" that was dragged kicking and screaming into the whole subject of "power delivery". Now, it's safe to say, I didn't just drink the KoolAide. I chugged the whole pitcher! We do performance mods. Power deliivery upgrades are "standard" proceedure now. Big smiles. Every time.
The OPs post makes sense to me. So, do the alternatives suggested here as well. I've spent some time with circuit breakers vs fuses with good sonic results. It seems that "breakers" are not as fast as fuses, and found that I need to drop a couple of values to stay on the safe side. The gear I've used for experimentation falls into the "replaceable" category. Not quite ready to whack away at my A-team gear just yet. Just wondering if anyone else has gone down this path?
Not trying to be judgmental here, but it appears that some of the posters got up this morning, slipped on a new pair of BVDs, and forgot to take the cardboard out of them? It's an audio forum. We sling ideas around. Some of them stick. Some don't.
I still don't quite understand what is the claim about the graphene sluggo. Is it that the sluggo minimizes the restriction of flow of electricity across the fuse holder and thereby improves the sound? Or, alternatively, that the graphene sluggo alters the flow in such a way that the sound is improved? If it is the former--that its highly conductive properties minimizes the flow restriction, then simply bypassing the fuse holder would be the ultimate fix. If it is the latter, it is harder to explain what type of alteration to the flow in the power side would have beneficial effects in the signal amplification side of an amplifier. Can anyone speculate on how the graphene sluggo works?
@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.
Wouldn't it make more sense to skip the sluggo, wire around the fuse & just get the SDFB? Mind you, if the existence of a fuse & the corresponding hardware impedes the flow of electricity, what's the effect of whatever mechanism the SDFB uses?
Count up the fuses in your system, amps, preamps, streamers, phono stage etc... how much cash are we talking here & what is the incremental benefit of each additional SDFB? It feels like the cable discussions to me where people say that they can hear a significant difference from replacing just a single cable (SDFB) but the overall effect of doing this for all is maybe a 5-10% improvement. So the overall effect is say 7% but you can hear a significant improvement from replacing just one single cable (SDFB)? Doesn't make sense to me.
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.
How do you sleep at night, go away with that nonsense.,.tonality ?? It’s gone from mildly entertaining almost laughable to ridiculous almost illegal. there’s an election coming perhaps put your name on the docket.
Whether the graphene sluggo minimizes loss through the fuse holder or alters the flow somehow can best be answered by someone who owns the digital fuse box and can bypass the fuse holder with a simple wiring change. Yet, it seems no one is making the attempt.
I might purchase a couple of sluggo's for the purpose of just seeing what it does without the digital fuse box. I know that is a risk during the trial period, but, I cannot ever recall changing a fuse in my system. I would then compare that to bypassing the fuse holder in my amp.
How do they actually utilize graphene? Graphene is only a single atom in thickness and not really easily utilized as of yet. I don't see how it will do anything but act as a marketing point. Powdered Graphene isn't really going to do that much from my reading. I could be incorrect but I don't think the development case for graphene is there yet.
Thanks for noticing. Made my day. I'd like to take create for this little tidbit, but it goes back a long way. Pretty sure it was a comedian one-liner from years ago.
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 . 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!
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.
a) Any affiliations with this verafi guy? (i.e., more than just an ecstatic customer? any financial/material arrangements? Did verafi guy load you with slugs for free? etc). Please clarify.
b) Eitherway, you will need to sit down with a blindfold, have spouse add slugs, swap slugs, etc and pass 23/25 times. If you can’t, its a no bueno (might be time to toss slugs in a lake and move on).
@gladmo Thanks for your thoughtful reply. I like a bit of warmth and openness, which includes the top end, although my direct hearing tops out in the 9K Hz range, last I checked. That combo, along with accurate as possible pitch, are what keep me listening for hours. The rest are bonus.
Mark’s linking of your post brought me to Agon. Other than checking here when researching an item, I don’t visit the Agon’s forums anymore because the site attracts a lot of trolls and the proudly and vocally ignorant, more than WBF and Decware, e.g. But unlike those, the people in charge here have a more laissez-faire attitude.
Big risk ,-0 safety without a fuse, and a brass slug Horrible conductor ,Copper has 3x better conductivity , 3 x less resistance or noise ,brass is bright vs Copper
that’s why I use a Not too expensive Hifi tuning Copper,gold fuse ceramic body
silicon filled to lesson any vibration ,gold over Copper conductor as well as end caps , and under $90 VH Audio sounds much better then stock Bottleneck
brass zinc buzz fuse that is a horrible conductor Bottleneck with a capital B
copper is a 63 in the Metals conductivity a buzz fuse 17 !!
@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.
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. 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!