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! :)

128x128gladmo

@verafiaudio

Yes, I am disappointed.  The Lux and the VTL would have been the best options, covering both tube and SS, but with other fuses downstream from the sluggo and SDFB, neither makes a good platform for analysis.  I guess I need to go amp shopping.......

@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.

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.

I had a SR purple fuse in my preamp, stock fuses in my class D monos and another SR purple in the streamer/DAC for the past 6 months or so.When this thread started, I removed the SR fuses and put stock fuses in everything once again. I listened to my system with these stock fuses almost every day for a week or so.

Yesterday, I received a partial order from Vera-Fi. I started off with replacing the stock fuse in my tube preamp with the "high purity copper" 6x23 sluggo. I allowed about 2 hours of running in as background music before plopping down in the sweet spot for some critical listening. I have a few test tracks that I know better than any person should. Immediately, I noticed exactly what @gkr7007 mentioned in his post on the previous page:

The largest difference for me was the expansion of the width and depth of the soundstage, and that sense of 3D surround. To a lesser degree there was a bit more dynamics and accuracy in the bass, and a general feeling of a smoother and more accurate tonality to female voices, sax, and piano. Not jaw dropping like some folks have reported, but an immediate and obvious positive change in the listening sessions. It’s a definite keeper for me."

I whole-heartedly agree. This is exactly what I experienced. And I mean exactly!

At the intro for Yello’s "Pacific AM" there is a sound like waves crashing. Before this sluggo, I could hear the same thing but without as many layers in the depth. It was a big improvement to me, I feel I have above average ears, but that’s pure opinion since I have nothing to compare to other than the the guys that work at stereo shops. I think it’s probably best to assume some will have better ears than me and some might be worse.

I like to pull my ever-so-wonderful Wife into these experiments. She is not an "audiophile" but she has come to appreciate the improvements in the system over the years. I just invite her to come sit and pick out a few of her favorite songs in the evening. After 5 or 6 songs, she mentioned "the stereo sounds really good tonight and that it’s noticeably "fuller" than it was last night.

Strange thing is that when I installed the purple SR fuses about 6 months ago (one at a time with plenty of listening before adding the other one for the streamer) I noticed strange things happened to the bass. Kind of that sound if you play bass through a driver loud while outside of the enclosure. Where it makes that bottoming out sound. It somewhat improved but never got to where I was hoping it would. There are hundreds of hours on those purple fuses by the way and they have been filpped around and cleaned terminals etc. When I put the stock fuses in last week, after about 6 hours, they started sounding better that the SR purple ones to me. How is this possible? When I installed the purple SR- back then it was an improvent over the stock fuses. Now, somehow the stock fuses sound better? I don’t know what’s going on with that, but I’m done with SR fuses and not going to examine any deeper.

I will say that there was no downside to installing this sluggo compared to SR fuse or stock fuse....only improvements. I guess time will be the true test. I’ll switch back to the stock fuses again in about 6 months to see which is better and report back (if no nukes have been launched).

For those of you who went all-in on replacing all your fuses with sluggos: was it the same amount of improvement each step of the way or was it less and less noticeable as you started adding more sluggos to your system?

Here’s a subject that simply drives some people nuts. Fuses.

Change the power fuse in a DAC or preamp and the sound changes, depending on the type of fuse you change to.

Why stop with tube rolling and fuse rolling??

I’ll open the chassis, give you a soldering iron and you could roll everything, roll every cap, thermistor, roll the transformer....Roll everything

Punch a few holes in the speaker box, see how the sound changes, keep adding holes, plug them back again, see how the sound changes.

You could also roll the listener, put different kinds of chemicals in him and see how the sound changes...ROLL EVERYTHING....NEVER STOP ROLLING...