KBL SOUND EXtrema USB

An experience with the ‘entry-level’ KBL Sound PRISM USB and many top analog cables from this brand made me curious about what their top-level digital interconnect has to offer. So here comes a review of the latest KBL Sound EXtrema USB.

Introduction

I remember quite well my first experiences with KBL Sound cables from roughly 10 years ago, so right after the company started. Already the first ones of those were encouraging enough to keep following the company’s development and progress over the years. Progress in terms of both, the sonic performance of their products, as well as even more aesthetically pleasing looks of the cables, but also of the elegant boxes they are delivered in. Today these are not only better but also more complete products that could satisfy the needs and expectations of the most demanding audiophiles.

The aesthetics of an audio product does not influence its performance, and yet, especially at a certain price level, it is something that customers expect to go hand in hand with it to form a complete, highly appealing product. So while it is not a ‘sine qua non’ condition for a low or mid-level component, it becomes one for the top ones. In my opinion, already a while ago, KBL Sound reached such a level. That allowed them to expand their distribution network not only across Europe but also across oceans. And that’s not an easy feat, as there are hundreds if not thousands of brands, each offering ‘the best’ cables, so to stand out among them a brand needs to offer exceptional ‘sounding’ and ‘good-looking’ performers.

KBL Sound EXtrema (that’s the original spelling) is the latest addition to the brand’s lineup. It is the top or ‘extreme’ line, as the name suggests. As far as I know, it is not based on a brand new concept, but rather is a result of a long, painstaking process of development of several solutions used previously in other lines by KBL Sound, and taking all the knowledge and experience that come with time. At the moment, the EXtrema line includes analog interconnects, speaker and power cables, and a full range of digital cables, including the tested USB, plus a very special and rare XDMI (developed for Taiko Servers users). As you may know, LampizatOr, maker of one of the best tube D/A Converters, has been working on XDMI input dedicated to Taiko users for a while. KBL Sound contributed to the efforts by preparing a proper link. But that’s a story for another time.

Just to remind you, my everyday reference is a relatively inexpensive David Laboga Custom Audio Expression Emerald Mk 2 (you can find the review of its original version HERE). It is the least expensive model (of three) in this brand’s lineup, yet so good, that it has been boldly competing against any tested cable of that type ever since I got it and never gave up without a fight. The other cable I had at hand for direct comparison with KBL Sound EXtrema USB was Tara Labs The Artist. Much later I got two more models, namely Tara Labs The Master with EVO grounding station, and a prototype of another one, that needs to remain unnamed for now, but that is supposed to cost even more than the tested one. Using my memory and notes, I also tried to find some similarities and differences with some of the top USB cables that visited my room in the past including David Laboga Custom Audio Ruby or Jorma Prime USB Reference.

Design and features

The information on KBL Sound EXtrema’s design is scarce which is nothing new for this (and many other) manufacturer. The point is that anybody with the help of a web search engine could buy the same conductors, plugs, sleeves, and so on, so laying out all the details of the design would only help those who make knockoffs and sell them at 1/5th of the price of originals. There is no reason to help them and the potential customers should base their decisions on the performance anyway.

So let me share what the manufacturer decided to make public knowledge. EXtrema USB design was developed using all the knowledge and experience gained over 10 years of designing and making audio cables. As the designer told me, they put everything they learned over those years into making the best cables in the brand’s history, and, in his words, they succeeded. Let’s be clear – the EXtrema cables, all of them, are meant for the top systems. Their prices reflect the ‘price-no-object’ (even if they are nowhere near the most expensive cables on the market level) approach and my job was to assess the performance of the USB variety.

As for the design. What I know, is that EXtrema USB features top-quality conductors made of the highest purity, monocrystalline silver and copper. These are additionally hand-polished for an even better sonic performance particularly in the treble range (according to the manufacturer). The hot and return signal runs in the cable are physically separated from each other to minimize magnetic interference. Also, the distance between conductors and shielding layers has been maximized to achieve an EXtremely (my guess is that is where the name comes from) low capacitance of the cable and to avoid phase shifts.

The main dielectric of EXtrema cables is air. To use it, which is a bit tricky, the designer placed conductors in Teflon sheaths. One of the key elements of the design is a specific spiral HyperSpace architecture which ensures that the conductors are kept away from shielding. As a result, the area where the wires and Teflon sheaths actually touch makes just a few percent of the total surface, so it is much lower than in most cables. As the manufacturer explains, such contact areas of conductors and shielding result in losses, which due to this particular solution are reduced to a negligible level.

The Teflon sheath layer is also quite rigid which makes it an excellent mechanical barrier, protecting against vibrations caused by the signal flowing through the conductor. There are actually a few layers of shielding, although the manufacturer doesn’t get into the details of the design, revealing only that those differ depending on application (type of cable). Then there is another multi-layer part used for highly effective vibration damping. That’s what makes this USB cable particularly thick – it is thicker than some speakers or even power cables (!).

The external sleeve is made of carbon-infused polymer for better high-frequency shielding. The manufacturer emphasizes that another property of the carbon polymer is the effective dissipation of electrostatic charge that reduces mechanically induced electrical noise and improves the uniformity of the voltage gradient within the insulating dielectric. As one can read on the manufacturer’s website, the final stage of production is a several-day long full frequency spectrum high-voltage conditioning process that allows to achieve better clarity, musicality, and resolution without the effect of fatigue. The idea is to shorten the necessary “break-in” period for end-users.

The EXtrema USB cable is terminated with solid, gold-plated A and B types USB plugs. While most of the cable is very thick and somewhat stiff, the last maybe 15cm at both ends are much thinner and thus more flexible making connections much easier. The EXtrema is not as heavy as it looks, and yet some support might be needed to avoid putting too much strain on the USB sockets on either end. KBL Sound EXtrema USB comes in a simple, yet elegant dark blue box. Inside, apart from the cable, one finds also a Certificate of Authenticity with the cable’s unique serial number, which is a nice touch.

Sound

The KBL Sound EXtrema USB cable was tested in my regular reference setup (see below) connecting JCAT’s USB XE card (see HERE)used in my custom Roon server and an input of the LampizatOr Pacific 2 DAC. It was directly compared to my David Laboga Custom Audio Emerald Mk 2 cable, but also to another loaner, TARA Labs The Artist.

Price-wise, my Emerald is the cheapest, and the EXtrema, by far, the most expensive cable among those three. As I’ve spent a lot of time testing cartridges and phono stages recently, I start listening to my digital setup using Emerald first to refresh my memory of its performance. Then, I move on to Tara Lab’s The Artist which I reviewed a few weeks earlier, and finally to KBL Sound EXtrema. The first switch confirms what I described in the aforementioned review (for another magazine), namely that The Artist is very transparent, clear (but not bright!), precise, detailed, and resolving cable.

The Emerald on the other hand is richer, more saturated, not quite as open, as crisp in the treble range, but a touch more weighted in the lower end. The Artist (around 3 times more expensive, to be clear) overall is a better cable, and yet again the DL Custom Audio Emerald MK 2 stands its ground proving that its price/performance ratio is exceptional. It is more relaxing, smoother, richer sounding, which better suits my personal preferences. The Artist will suit particularly well those with a warm and rich sounding system who want to add more clarity or ‘brighten’ things up without actually making the sound bright, or those who love transparency and detail über all.

My system (regardless of which of my sources or amplifiers I use at any given moment) always delivers performance on a bit warmer, richer side of things without pushing these features over acceptable limits. It was built to prefer natural sound over super-neutral one, coherence, and smoothness over hyper-transparency, and being super-detailed. That’s how I like it. With The Artists, it sounds ‘fresher’, and crispier, and it is hard not to like it, yet, in the longer run, I prefer the more relaxed, slightly laid-back sound that Emerald MK 2 provides.

Now, to the point. The next step is switching to the KBL Sound EXtrema. I replace The Artist with the latter and continue to listen to a live performance of Ahmad Jamal and his band entitled simply „Live in Marciac”. Even before the whole band joins at the very beginning, it is clear, that with EXtrema the spatial aspect of the presentation improves, and not by a small margin, over either, Emerald MK 2 or The Artist. The acoustics of the room and its size become more apparent, and not by begging for attention if you know what I mean, but by just being there or opening the window to the music more widely for me.

When the whole band enters moments later the depth of the soundstage they occupy becomes clearly even more impressive while still realistic, and imaging of the very well differentiated and separated in the space phantom images becomes more three-dimensional, gains some weight, if you will, hence the instruments seem more palpable, more present than with any of the other two (way cheaper – just a reminder) competitors. That’s a huge plus in my book as I love spatial and palpable presentation almost (!) above all.

After all the instruments finally join, also another significant improvement jumps out at me, even though it happens on the micro level of the presentation. Because, it is the abundance and clarity of all those tiny little information, that fills in, enriches, and improves every aspect of the presentation quite significantly compared to the other two USB cables. It is not the type of a ‘lifted veil’ revelation but rather a realization that there is more information in all those highly familiar tracks that have always been there but now they are easier to notice and, again, make the whole complete and even more realistic.

The effect is similar to that of turning the volume up when the details sort of jump out from the mix, except in this case they don’t, not really. They are clearer, but not ‘extracted’ or pushed out from their surrounding. I haven’t touched the volume control, to be clear, and yet when something is meant to jump out, like a powerful collision of a stick and a cymbal or drum, they grab my attention even faster and easier than before. Adding the KBL Sound EXtrema to the setup creates an impression that there is more, significantly more information in the sound which translates directly to a more essential, denser, richer, and ultimately more convincing musical experience.

While listening to David Gray’s „White Ladder” with the EXtrema I bask in the pure and rich beauty of incredibly natural, organic vocals and the sound of an acoustic guitar. It’s not quite what one would call an audiophile-grade recording and yet due to this organic feel of these two features, it becomes more immersive than almost ever before. Almost, because what it reminds me of is a sound that I know from some very good 300B SETs. I keep using the very tube-like sounding GrandiNote Shinai for the test, yet with the EXtrema USB between the server and my tube DAC, the sound coming from the speakers reminds me even more what I love a good 300B SET for.

The remnants of the ‘solid-stateness’ of this fantastic amplifier seem to disappear completely. Importantly, it happens without eliminating its strengths such as deep, powerful, hard-kicking bass, which is usually quite hard to get with an 8W SET, unless the matching with speakers is perfect. There were only a few indications sonic-wise of the solid-state design of Shinai before, but the tested cable through their absence, reminds me that they existed before and now they are mostly gone. Or that’s at least how it feels to me. And, to be clear, as a 300B SET fan, I love this feature of the KBL Sound’s top USB cable! It, simply put, adds a sort of natural, analog finish or polish to the performance. It is a subtle change, one that seems more like a feeling, a vibe than something one can clearly hear or point out. Yet, considering that what many people are after is getting rid of all the hints of a digital origin of the sound played from files, it is a highly welcome feature that only some, usually quite expensive cables offer so efficiently, as the EXtrema.

Another album, that EXtrema USB turned into a special experience was Christian Sands’ „Embracing Dawn”. It’s filled with moody, well-recorded compositions where Christian’s guitar doesn’t always take the lead. I listen to it late at night so naturally at quite a low volume level. For all the details and intricacies of the music to be so clearly, yet unobtrusively presented in such conditions, all the components in the system have to play their role perfectly. The deciding factor is the amplifier-speaker relation, but the former has to be fed a high-quality signal to ultimately convey every piece of information even if the low level makes it difficult.

The tested KBL Sound’s top USB cable does play its part extremely well. Starting from the deep, powerful, colorful, and when needed quite tight bass, to the crisp and shiny metal cymbals, and the richest of them all, smooth, dense, and beautifully natural midrange, it conveys the whole wealth of information in a pure, and orderly way. The resolution is magnificent, as well as the ability to differentiate the information on both micro and macro levels, ensuring that fantastic dynamic range, as well as the texture, and timbre are accurately presented. As all these elements are skillfully put together, what ultimately comes out of the speakers is a perfectly coherent, full, and highly engaging performance that forces me to add more and more albums to the playlist despite the late hour.

I sort of forgot how much fun on the one hand, and how different experience on the other, is late-night listening. With the ambient noise of a busy city (and that of activities of other family members and neighbors) lowering to a negligent level, listening to music, despite the low volume level, requires me to be more attentive, more focused and that translates to a different kind of listening experience where tiniest details matter even more. That means I demand more from my system, and KBL Sound EXtrema USB significantly enhances its performance making listening easier, more engaging, and more gratifying.

Still the same night, I decide to switch gears and mood and play „The Twilight Of The Gods: Soundtrack” (by Hans Zimmer, Omer Benyamin & Steven Doar), and finish the (very late) night with „Dune Part II” (also by Hans Zimmer). These are monumental, powerful soundtracks that include very, very deep, and powerful bass. There are parts with huge space, choruses, and many more features that are quite challenging to present convincingly even when listening at normal levels, let alone such low ones.

Again, the capability of the whole system, including the KBL Sound EXtrema USB cable, to present all these elements of the music with clarity, and transparency in a quiet, yet powerful, deep way is truly impressive. I’ve mentioned it before, but these albums shine the light on this quality yet again. The space, depth in particular, even though the width seemed amazing as well, is stunning. The clearly defined phantom images are clearly, precisely placed either closer or further away from me, in the axis, off the axis, to the left, to the right, to the far, far left, and far, far right. An impression of being in a large venue while precisely ‘seeing’ all sound sources is uncanny (just a quick reminder – it is late at night so I use only some ambient light).

The very next day to slowly start the day I play „Bach jazz”. Yup. That’s a jazz trio playing Bach. The piano plays the main role in many tracks with drums and double bass supporting it gently in the background. These are very good recordings and the EXtrema USB acted on it presenting, first and foremost, the beautiful, warm, a little dark timbre of both piano and bass in an incredibly natural way. The drums are precisely placed on the stage a few meters behind the piano, as is the bass, although more to the side. Yet, I can hear a lot of beautifully differentiated, intricate details of the performance of each musician. The whole, with KBL Sound cable in my setup, has this intimate vibe of a tiny concert held in quite a small room, my room.

One of the albums that I also listen to with the cable under review is David Gilmour’s new „Luck and Strange”. When it came out I listened to it with my USB cable and… on the one hand, it was exactly what I expected from this artist, on the other it somehow didn’t reel me in, so to speak. It was good, but not a fantastic experience, as some reviews claimed it to be. It changes the second time around with EXtrema in the system. Now, whether it is because it is the second time, or because of the change of the USB cable is debatable, but the third and fourth times are more like the second one, so my bet is on the cable. This time I am more involved in the music and more focused on it. It is not about better bass, treble, space or any particular quality audiophiles love so much, but rather about the experience as a whole. It is just more immersive, and more… personal with the music seemingly more present, more here and now.

An Addendum

Just days before finishing this review I received two parcels. Inside one of them, I found a prototype of another USB cable for another manufacturer (I can’t name names yet), one that will most likely cost even more than EXtrema. Another contained a higher model by Tara Labs, The Master with an EVO grounding station. I had to jump at the possibility of comparing three similarly priced USB cables to at least get the first impressions of how they all compare to each other.

All of them are insanely good performers, ranking among the very best USB cables I’ve ever tested in my system. Each of them is a bit different, with the EXtrema and the unnamed being more alike than the Master, though. The tested KBL Sound top-of-the-line offers a slightly deeper, even more weighted bass, than the other two, although the unnamed one comes very close in this regard. The Tara Labs, same as the Artist before, keeps even the deep end tighter than the other two. It still has quite a punch, and the extension is impressive, but since it’s the tightest and (due to the EVO station, as it seems to me) offers the lowest noise level, it seems the leanest (which is not necessarily true).

Master w/EVO has a tiny edge over the other two when it comes to the other extreme, delivering the crispiest and the most open sound. Overall it seems that EXtrema’s center of tonal gravity is set a bit lower which results in a sound that seems a bit denser, and more weighted. To be clear, all the differences I pointed out are tiny (!), and you will need a really good system for them to make a difference for you. Otherwise, all three will offer the same, amazing level of performance.

I am not even going to go into how resolving, how tonally rich, how natural, and how analog (!) all three sound, as at this level these features are basically a must. I can’t say these are the best cables in the world as there are many I haven’t listened to, and the best cable in any setup doesn’t have to be one in another. Let me just say instead, that I am really glad that manufacturers treat USB cables more and more seriously, and as a result, we get more and more refined products to choose from. No doubts, KBL Sound EXtrema belong to the best money can buy today.

Summary

For the reasons explained above I am not going to call KBL Sound EXtrema the best USB cable in the world. I can, though, recommend it as one of a handful of the best and most versatile (as the genre of music doesn’t really matter) I’ve ever listened to in my system and one that offers a peak performance as long as the rest of the setup is capable to follow suit.

The absolutely key feature, in my opinion at least, is this incredibly analog (or non-digital, free of digital artifacts) and natural sound you can get with it. All the rest, meaning everything one demands from any high-end component, is also there and it seems completely natural, expected. KBL Sound EXtrema is highly resolving and refined. It brilliantly presents both the large and the smallest scale dynamic and tonal contrasts and details. The sound with it is smooth, beautifully rich, coherent, and also spatial. It delivers music in a lively, energetic, and palpable or very ‘here and now’ way. It differentiates recordings extremely well, and yet it will let you enjoy not only the very finest, hi-res files but also those of a ‘regular’ quality. What any true high-end component should be about, if you ask me?

You need to consider one thing though, when purchasing this cable for your system. Adding the KBL Sound EXtrema to your system involves a serious risk! You may (most likely will) get addicted to listening to music (even more than before), hence it is likely that you will spend a lot more time in your listening room. You’ve been warned! Now, get a loaner and check it out for yourself.

Prices (when reviewed):

• KBL SOUND EXtrema USB 1,2 m: 4.535 EUR (1.330 EUR per each additional 0,5m)

Manufacturer: KBL SOUND

Technical specifications (according to the manufacturer):

• Conductors: ultra-pure monocrystalline silver and copper, polished by hand, gauge: 20 AWG
• HyperSpace Architecture
• Dielectrics: uncolored PTFE, air, Kapton, polyolefin, polyurethane
• Electrostatically dissipative carbon polymer used externally reduces mechanically induced electrical noise and improves the uniformity of the voltage gradient within the insulating dielectric
• Version USB 2.0 A/B type
• Standard lengths: 1.2 M, each additional 0.5 M upon order

Associated equipment:

• Digital source:  a custom passive server with WIN10, Roon, Fidelizer Pro 7.10, JCAT NET XE, and JCAT USB XE cards with FERRUM HYPSOS Signature power supply, KECES P8 (mono) linear power supply for the server, JCAT USB Isolator
• D/A Converter: LampizatOr Pacific 2 +Ideon Audio 3R Master Time (USB signal regenerator)
• Analog front end: J.Sikora Standard MAX turntable, J.Sikora KV12 & J.Sikora KV12 MAX Ziconium Series tonearms, AirTight PC-3, Le SON LS10 MKII, and Audio Technica PTG33 Prestige cartridges, Grandinote Celio MK IV & ESE Lab Nibiru V 5 phono stages.
• Power amplifiers: GrandiNote Shinai, Circle Labs M200, Art Audio Symphony II (modified)
• Preamplifier: Circle Labs P300
• Loudspeakers: GrandiNote MACH4, Ubiq Audio Model ONE Duelund Edition.
• Interconnects: Bastanis Imperial x2, Soyaton Benchmark, Hijiri Million Kiwami, Hijiri HCI-20, KBL Sound Himalaya II XLR, David Laboga Expression Emerald USB, David Laboga Digital Sound Wave Sapphire Ethernet
• Speaker cables: Soyaton Benchmark MK2
• Power cables: LessLoss DFPC Signature, Gigawatt LC-3
• Power: Gigawatt PF-2 MK2 and Gigawatt PC-3 SE Evo+; a custom power line with Gigawatt LC-Y in-wall cable; Gigawatt G-044 Schuko and Furutech FT-SWS-D (R)
• Network: Silent Angel Bonn N8 + Silent Angel Forester F1 + optical LAN isolator
• Racks: Base VI, Rogoz Audio 3RP3/BBS
• Anti-vibration accessories: ROGOZ-AUDIO SMO40 and CPPB16 platforms and ROGOZ AUDIO BW40MKII feet, OMEX Symphony 3S, Franc Accessories Ceramic Disc Slim Feet and Wood Block Platform, Graphite Audio CIS-35 and IC-35