Sluggo - For Use with SDFB

I recently replaced the stock fuses in both my SSZ and Tempus PSU with the Graphene Sluggo.

Even at the start there was a sense that something had shifted, but this is not the kind of upgrade that shows everything in the first hour. In my case it really came into its own after about 300 hours. The first 50 hours the treble had a slightly tighter character and the mid-bass felt restrained. Around 150 hours the presentation started to relax, with better flow and more natural layering. By 300 hours dynamics felt settled, micro-details became more apparent, and the whole system sounded more connected.

What stood out most to me was the neutrality and transparency. It does not push the tonal balance in any direction, it simply lets the system speak for itself. Highs extend cleanly without harshness, keeping fine texture and air. The midrange has a natural presence with good retrieval of subtle detail. Bass is well controlled, evenly weighted, and separated with clarity.

On the SSZ, highs became smoother while keeping resolution, and the soundstage felt more open in both width and depth. Vocals gained more dimensionality compared to the stock fuse. On the Tempus PSU, tonal balance stayed consistent, but resolution improved across the range, making instrument separation easier to follow.

Mark at Vera-Fi has been great to talk to. Every question I asked was answered with detail and warmth, which made the whole experience more positive.

After this I plan to gradually replace all the fuses in my system with the Graphene Sluggo. For anyone using SSZ or Tempus PSU who wants more resolution and detail without altering the system character, this could be worth considering.

I've had experiences with three different sluggo options, the high purity copper version, high purity copper with a gold immersion, and the graphene sluggo. The graphene sluggo was far and away my no. 1 choice; graphene is the best conductor of electricity that exists, and the graphene sluggo has been vapor-deposited with a microscopic layer of the compound. Graphene is actually just a single molecule of carbon, and though the microscopic layer deposited on the sluggo is infinitely thin, it still transmits current at a 70% higher rate than either of the two other options. The sluggo uses the proven concept of "skin effect," where the lion's share of the current travels across the surface of the sluggo. The graphene sluggo was absolutely superior to anything else I had access to, you can read my original review here:

https://positive-feedback.com/reviews/hardware-reviews/vera-fi-audio-swiss-digital-fuse-box/?highlight=graphene

The Naiu Ella Stereo Amplifier is the only amp in my collection of gear that has an amperage rating higher than 10 amps -- that wouldn't allow me use the more flexible Infinity Fuse unit that's user-programmable. The Swiss Digital Fuse Box arrived in a black case as opposed to the usual silver case, which was a really good look! Hookup was easy, and I robbed the Core Power Piggy Tail from my analog system to hook the Naiu Ella to the SDFB. After it burned in for 24-or-so hours, I took an extended listen, and the SDFB in the system with the Ella amp now showed the same level of effortlessness and clarity I noted in my original experiences with it in my all-analog system. And my principal assessment of the SDFB remains consistent -- the Naiu Ella in the digital source system now plays with more control and limitless dynamics -- it's almost like a completely different, more powerful amplifier. Very highly recommended -- once you hear your system with the SDFB, there's no going back!

The Graphene Sluggo brought a more natural sound all around. Thanks Mark

I’m very impressed with the SDFB. I’ve used many high-end fuses before, but most tend to alter the tonality, introduce noticeable midrange distortion, and result in bloated, loose bass. In contrast, the SDFB preserves the original tonality while significantly improving bass performance—offering greater detail, tighter control, and a clear reduction in distortion across the entire spectrum. The soundstage also expands substantially.

I briefly compared it directly with a fuse-less setup and can confirm that while there’s a slight reduction in body and bloom, the SDFB is the closest I’ve heard to running without a fuse.

Killer combination with SDFB

As a late-comer to the fuse-upgrade culture, I'm glad that I finally stepped into the realm of SDFBs. I currently use a pair of Dutch and Dutch 8Cs sourced by Grimm Audio Mu2 as reference. I replaced all three fuses with SDFB and Graphene Sluggos. On my 8Cs, not only it opened up the soundstage, it did so without any sacrifice, the soundstage is more defined and the presentation is embodied with better clarity and even better focused - large orchestral passages become more layered, the tonality more visceral and congested sections more relaxed without sounding "loose". The additional graphene added to my Grimm Mu2 tightened the overall focus even more and further enhanced the overall realism of my system. This upgrade to me is fundamental and astounding. It ranked among the best upgrades that I'd ever experienced!

The single most effective "tweak"

Amazing, pretty much sums it up. Everything I’ve read about the SDFB, I found to me true in my 300 b amp.

This is my 9th SDFB! I obviously like them!