pl | en


KBL Sound

Manufacturer: KBL SOUND
Price (when reviewed): 9390 EUR/1,8 m

Contact: KBL SOUND
ul. Bednarska 26 lok. 7
00-321 Warszawa ⸜ POLSKA


Provided for the test by: KBL SOUND


images KBL Sound, Marek Dyba

No 233

October 1, 2023


KBL SOUND is a Polish audio brand specializing in the production of interconnect, speaker, and power cables, although the range also includes power strip and vibration absorbers. In celebration of its 10th anniversary, the company is introducing a new EXTREMA line. Its first representative is the top AC power cable we tested.

EN YEARS IS A LOT AND A LITTLE depending on the perspective. On the one hand, a lot can happen in such a period - let me remind you of the last decade and all we have been dealing with globally or even just domestically. One can also think of it as quite a long period looking through the perspective of the company's operations and development. The very fact that it has existed for so many years is proof that it must be doing something right. The market usually quickly verifies failed experiments and simply gets rid of them. But on the other hand, there are, after all, brands and companies that have existed for several decades or even hundreds of years (although not in the audio industry), and compared to them, we can say that KBL Sound celebrating ten years of existence is just a "kid".

Nevertheless, a kid has been continuously growing, developing, learning, and gaining experience for a decade now. Each of these elements is necessary to offer better and better, more advanced, higher quality and better-performing products. This is the kind of progression we see when looking at KBL Sound's offer. The latest addition to the range, as Mr. Robert told me, heralding a whole new top series, is the Extrema power cable, which he delivered for this review.

He also told me, that work is already underway on next products that will complete the range of the Extrema series, but, the development is not rushed, so it is difficult to say for now when their premiere will take place. It would seem that the upcoming Audio Video Show 2023 in Warsaw will be a good opportunity to do so, but it will only be seized if the next product is actually ready.

I like and fully approve such an approach at times when there are still a considerable number of unrefined products hitting the market when an exhibition, trade show, or other such event is approaching. Judging by the power cable personally delivered by Mr. Robert, one can expect that each subsequent product in the Extrema series will be refined to the smallest detail before it sees the light of day.

As I’ve already mentioned, the designer himself brought his product for the test. The very first thing he showed me was not so much the cable itself, but.... its packaging. Perhaps you have already seen it in the photos from the press release and know that it looks great and elegant. What you can't see in the photos is that the design allows you to fold it easily into a flat piece of cardboard, and then, when it’s needed again, bring it back to its original form within seconds. It’s a detail, unimportant for the sonic performance, yet it makes the life of Extrema’s owner and storage of the box easier. A seemingly small detail, but simply a very cool one.

Extrema AC

WHILE ROBERT spent some time with me, during which we checked whether using more than one Extrema AC cable produced a noticeable change, or whether one would suffice, in terms of design he only told me that all the information he wanted to share was on the website. The point is not to give a ready-made recipe to those, and there are plenty of them, willing to copy a particular design.

The solutions used in KBL Sound cables are the result of many experiments and accumulated knowledge and experience, all of which required effort, time, and investment of considerable financial resources. Hence the decision to share the fruits of labor rather than the means to achieve similar results. Therefore, in describing the cable, I am left with relying only on the little information available.

As those of you who have read some previous reviews of the brand's power cables probably already know, in addition to specific series (Fluid, Zodiac, Red Corona, and Himalaya II, and now Extrema) there is a separate one used exclusively for power cables called TriKord Power®. It includes Mirror Master Reference, Himalaya PRO II and, as of now, Extrema models. As the manufacturer says, the name TriKord comes from the triple (TRI) system of independently routed conductors:

The Extrema power cable was engineered as part of the exclusive TriKord Power line, initiated by KBL Sound in 2018. In our intention, it is an sophisticated cable for the very best systems. It is obvious that every design of any manufacturer is burdened with compromise decisions. Usually, it is the cost of materials or their technological imperfection, sometimes also the difficulty of making. In the Extrema cables, we pushed all construction barriers aside and we conceived a cable in which we did not have to accept any compromise. What we intended to do and sounded better has been implemented, regardless of cost implications., accessed: 09.09.2023.

The concept of the TriKord Power Series cables is to group the conductors in three asymmetrical bundles in each of the three runs. The main advantage of this solution is the ability to treat or tune each of these runs separately. This is important insofar as the role of each of the three runs is slightly different, and fine-tuning each of them separately minimizes the compromises necessary when it is not possible to treat these runs separately. Thus, TriKord Power technology is associated with a spatial topology of conductor routing, special damping, and individual shielding.

The KBL Sound Extrema cable is.... thick, really thick, even if it is still a bit short of the record-breakers in this regard. What's a bit surprising is its weight, because, in contrast to its looks, it's quite a bit lighter than what you might expect. The thing is that the thickness is the result of a proprietary topology that the manufacturer calls HyperSpace. As Mr. Robert explained to me, the idea was to maximize the spread (increased distances inside) of each run. Equally distant are the broadband shielding layers. Combined with appropriately tuned elements for vibration damping, they are supposed to allow excellent, or, as the series name suggests, even extreme performance.

The conductors used in Extreme AC are ultra-thin wires made of mono-crystalline copper with the highest purity and surface smoothness. There are 597 of them in total, resulting in a thickness of 9 AWG. In developing the Extreme cable's geometry, the designer drew on his experience from working on previous versions of the TriKord Power series cables. He used several dielectrics in his design, including Teflon, Kapton, polypropylene, cotton, polyolefin, and air.

The manufacturer optimized the vibration damping and shielding system specifically for the role of each individual run. This, he said, allowed the cable to achieve better performance, also due to minimizing the effects of mutually interfering magnetic fields generated by the current flow.

The cable is terminated with top-of-the-line Furutech Fi-50 plugs using, among other things, for anti-static purposes, nanotechnology. The contacts of these plugs are made of pure copper subjected to the α (Alpha) process, i.e. cryogenization and demagnetization. The body of Furutech's piezoceramic plugs is armed with silver-plated braided carbon fiber, and a coating of acetal copolymer with damping and insulating properties.

It is important that, despite this impressive thickness, the cable is quite flexible which makes it easy to connect, and route in the system. Even if, as in my case, there is not much space behind the devices. It's also not very heavy, so the weight of the hanging cable doesn't put too much strain on the plug and socket in the device.

I asked the designer about a possible suggested application(s), after all, more than one manufacturer suggests that a particular design performs better with more current-hungry components, and others with, say, sources. According to Mr. Robert, the Extrema AC can be used to power any device, although the price suggests that these should be high-end products. The performance of the cable was also checked by the manufacturer in combination with a power strip, and based on the results of those tests, he recommends such use as well.

The standard cable length with IEC 15A plugs is 1.8 meters. A version with C19 20A plugs required by some power-hungry devices (usually powerful power amplifiers) is available on request. This length is not accidental, as Mr. Robert told me, it is the optimal length and the shortest one allowing the best sonic effects. It is possible to order longer sections (adding length by half a meter its multiples) for an extra charge.


˻ HOW WE LISTENED ˺ We started listening to my system together with Mr. Robert using first one Extrema power cable feeding the source, then added a second to the preamplifier and finally a third to the power amplifier. Each successive addition increased the positive impact on the sound without exaggerating any of its aspects. So I thought it worthwhile to describe the impact of both one and several of these cables in the system. The Less DFPC Signature cables I'd been using for years served as a reference. They are much cheaper than the ones tested, but they have been with me for years, so it is easy for me to compare all the others to them, regardless of the price level.

For the main part of the test I used my reference system, in which the digital signal was converted into analog by the LampizatOr Pacific 2 DAC, after which the analog signal was sent to a Circle Labs P300 preamplifier, and that to a Circle Labs M200 power amplifier driving GrandiNote MACH4 speakers. The components were connected using Soyaton Benchmark analog signal cables. Later, the interconnects were replaced by KBL Sound's Himalaya II series products. Finally, the Pacific 2 gave way to another excellent DAC, the Playback Design MPD-6, and I swapped the two-box Circle Labs amplifier for a GrandiNote Supremo reference integrated. In this configuration, balanced interconnects (Soyaton and KBL Sound) replaced unbalanced ones (of the same brands).


THE LESSLOSS POWER CABLE I HAVE USED FOR YEARS are by no means among the best I know of, but their sound-to-price ratio is outstanding, far better than most power cords I know. So they offer a class of sound (impact on sound, to be precise) far superior to that suggested by their price level. They ensure neutral, well-balanced, uncolored performance, without changing the character of even very expensive components they power, even if they can't show their full potential. Never before, in any combination, the LessLoss cables let me down, and that's why (leaving aside the obvious financial aspect of replacing four power cables with much better, i.e. more expensive ones) they have been with me for years.

Replacing one of them for LampizatOr Pacific 2 with the Extrema chord introduced a clear and easy to notice and to appreciate change in the sound. The most obvious difference was the filling and tightening of the lower midrange and bass. The thing was not an artificial effect, it was not about cable adding something to the sound, but rather, judging by the proper balance of the entire range and the coherence of the sound, unleashing the potential of the source and, in effect, the entire system. I've heard this even with the MACH 4 speakers, which, after all, are not the masters of the lowest bass. I could hear it because this change affected the range from the lower midrange all the way down to the very lowest notes these speakers were able to reproduce. With the tested cable it even seemed as if the bass extended even lower than before, that it somehow got even more powerful and effortless at the same time.

As for the extension of the frequency response, this was of course an illusion resulting from a stronger weighting and saturation of the lowest reproduced sounds, because, after all, a power cable, even the best one in the world, could not change the laws of physics, and make the speakers reproduce sounds that they were not capable of reproducing before. Nevertheless, it was a clearly positive, even desirable change, especially since it did not involve a loosening of the bottom end at all, it did stay really tight.

What’s more, even those maybe even tighter, better filled, more colorful lowest bass notes did not lose anything of their speed and compactness that I highly appreciate the Italian speakers for. As demonstrated by a number of recordings in which low bass played a significant role, the Extrema also improved its differentiation and resolution. The sound was thus richer, fuller, with better-shown texture, simply truer, and thus more interesting, more strongly engaging to the listener.

All the more so because this effect, heard for example with double bass or piano on ISAIAH J. THOMPSON's The IT Department album, was reproducible and was not limited to better sound saturation and filling, or better differentiation. Also the dynamics, more so (but not only!) at the micro level, gained with the Polish cable, which directly translated into more faithful presentation of recordings, into their credibility. With Extrema the role of both instruments on this album seemed to increase, there was "more" of them.

I don't mean the number of instruments, obviously, but the volume of their sound. Both of them gained body, so to speak, as their large resonance boxes and the role they played in creating the sound were better conveyed. Therefore, every keystroke or string pluck had more weight, and additionally, the attack phase was more clearly marked (LessLoss, in comparison, however, blurs the front of the attack a bit), and this happened without shortening the decay. There was also no artificial hardening of the sound. The double bass, though tighter, though its strings were more springy, was still naturally soft due to the box input. Drums, on the other hand, became more springy, but you could still hear the sticks hitting the flexible, "responsive" membranes, and the latter responding in kind. Both were nicely differentiated allowing me to fully appreciate the talents and skills of the musicians.

A similar effect appeared on KITARO's Kojiki album. The combination of synthesizers and orchestra, the momentum and freedom of the latter, the majestic, powerful-sounding drums, but also the low electronic sounds - all of these emphasized the "gains" from swapping the LessLoss power cable for KBL Sound Extrema. The sound, which was best heard in moments of climax, piling up of the most powerful, dense sounds, was freer and more open.

The power and fullness of the sound increased the realism of the presentation even more and gave the impression of more physical perceptions of the events from the chronicle describing the founding of Japan (i.e., the "Kojiki") so creatively and beautifully told by Kitaro using music. This way of presenting the music made my involvement in the events on stage even greater, and more natural than ever before. I found it even harder to get away from this album and go back to assessing the tested component.

Later, listening for who knows which time in the last two, maybe three months to the Who is... The Lion, the Wolf and the Donkey? discovered some months ago by chance on Qobuz, my attention, for a change, was focused on the spatial aspects of the presentation. This is because it was easy to notice that the effect of swapping the power cable for the Extrema was similar to the one I felt when swapping the Lithuanian LessLoss speaker cable, which had also been a part of my reference system for years, for Soyaton Benchmark. For just as with the latter, the Polish power cable contributed to a noticeably larger, more open space that appeared in front of me, with better differentiation of layers and placement of individual, large, three-dimensional phantom images on the stage.

A similar impression accompanied me when, after finishing a prepared test playlist, Roon started its „radio” and selected a piece by Queen titled Another One Bites The Dust. Surprised by its appearance, I „watched” how far beyond the spacing of the speakers the sounds appeared and how far behind the line connecting them, but also how they moved from one side to the other. Of course, I had to listen to the piece with my cables as well, and then again with the KBL Sound Extremes, which only confirmed and even reinforced my initial impressions.

The tested cable feeding the Pacific 2 DAC directly translated into a noticeably better presentation of all spatial aspects of recordings, as long as these were properly recorded. Selecting a few more albums with particularly well-recorded spatial aspects confirmed that it didn't matter whether these were recordings capturing a natural space of the venue (live albums), or one created entirely in the studio. Each time, the performance re-created in front of me was very impressive without exaggerating the spatial aspects, i.e. showing it convincingly yet realistically.

Another element brought by the tested cable, further enhanced by adding two more KBL Sound Extrema power cords to the system (for the preamplifier and power amplifier), was the higher energy of sound coming from each instrument, combined with what felt like a truer presentation of their timbre and texture. This energetic aspect was so convincing that it seemed as if this energy was flowing directly from the instruments as if there were (almost) no losses from the whole recording process nor playback, which always severely limit this aspect of sound. Obviously, I don't mean to say that with Extrema chords presentation sounded quite like a live performance, but it was definitely closer to what I remembered from concerts than what I had with the LessLoss cables.

This was also true for the top of the band. I listened to several albums with brilliantly recorded drum cymbals and other percussion instruments, both metal and wood to learn more about upper midrange and treble presentation with three KBL Sound Extrema cables in my system. It was clear to me that in this part of the range too, one could hear more energy and a combination of seemingly contradictory elements, i.e., weighting/filling with sonority, openness, and „freshness” of sound. There was more metal in metal elements, i.e. they were heavier and more vibrant at the same time.

That's why the brilliantly differentiated percussion instruments on PATRICIA BARBER's album, but also the bamboo instruments on JOHN KAIZAN NEPTUNE's, or Steve Gadd's cymbals sounded incredibly powerful, true, and exciting. The already mentioned, very good, resolution obtained with the tested cables provided an abundance of information, yet combined into a smooth, coherent, natural whole. That’s why despite the impressive resolution and clarity of the sound it does not feel particularly analytical, but rather like a very rich, complete sound that allows one to study selected aspects or details but does not force one to do so.

Finally, let me point out one more aspect of the music presentation, which at first was somewhat hidden by the choice of test tracks. Eventually, however, I began to pay more attention to the vocals. My experience with high-end power cables shows that they usually bring more "good" to the sound at the band's extremes, rather than in the midrange. This is not an ironclad rule, it's based on my observations so far that are confirmed in most cases. This is not to say that power cables don't have an impact on the midrange, only that usually it is lesser in this part of the range.

I had a similar impression with the KBL Sound Extrema, at least until I added several tracks not only with vocals but also with guitars in the leading roles to the playlist. In each of these cases, the foreground was magnified a bit with the Extremas and thus it appeared closer to me. It did not, however, move the foreground in front of the line of connecting speakers. Yet, the power of three power cables used in the system simultaneously turned all the vocalists and guitarists into more "present", more impressive (not showy!), more focused beings.

The tested cable did not so much boost the midrange, but made the presentation of the abundance of information from this part clearer, and delivered in a more expressive, more touching way. That's why STEVE RAY VAUGHAN's guitar and vocals, but also those of DAVID GILMOUR or MARK KNOPFLER almost materialized in the foreground, sounding more expressive and, as a result, more engaging than with my cables. That is exactly what I expected from my system as a whole, and the tested KBL Sound Extrema power cables allowed it to fulfill my expectations even better.


EVEN THOUGH THE KBL SOUND EXTREMA power cables, if only by its pricing, are intended more for even more expensive systems than mine, I could still hear perfectly how much it contributed (and the three combined contributed even more) to the performance of my setup. By using the term "much" I'm trying to emphasize its (or their) superiority over the LessLosses counterparts I use every day, not the objectively huge impact on the sound of the system - we're talking about (important!) a few percent which at some (high enough) level may turn out almost priceless as they are harder and harder to achieve the more expensive a system is.

Plugging in just one top-of-the-line KBL Sound power cable into the LampizatOr Pacific 2 reference DAC produced unequivocally positive and desirable results, and adding two more to power preamplifier and power amplifier further enhanced them by showing that there are still unused reserves of quality in my components worthy of exploring. It’s not news to me - I know these components, DAC in particular, deserve higher quality power cables, but as I mentioned before, it’s a matter of a significant amount of money that such an upgrade would require and that I can’t afford at the moment. Yet, if I could, I would seriously consider this particular model.

The presentation with Extrema power component(s) becomes more resolving, energetic, fuller, more spacious, and more engaging. What's important for me, the tested cables didn't take away any of its advantages from my system but enhanced many of its qualities. The end result was a natural, engaging, relaxed, musical sound with great, tuneful, and perfectly controlled bass, brimming with energy, dynamic, yet coherent and smooth.

It is also indeed, as per the manufacturer's declaration, a versatile proposition, because its advantages can be heard both with the LampizatOr’s tube "DAC", and the solid-state Playback Design’s, with the Circle Labs two-box amplifier and with the top GrandiNote class-A integrated. Long story short, if you’re looking for an AC power cable for your top components regardless of their type, you should not overlook KBL Sound Extrema in your search. There is a good chance that it will prove to be a final touch for your setup!

Technical specifications (according to the manufacturer):

• mono-crystalline copper conductors with the highest purity and surface smoothness
• stranded construction with a total number of 597 superfine wires and a cross-section of 9 AWG
• 3 asymmetrical bundles in each of the three runs
• insulation: Teflon, Kapton, polypropylene, cotton, polyolefin, air
• original technologies: TriKord Power ®, 3D ScreenPoint, HyperSpace Architecture
• tuned system of vibration damping and broadband shielding, individualized for each of the three runs
• terminations: Furutech Fi-E50 NCF(R) and Fi-50 NCF(R)
• optional terminations with IEC Furutech Fi-52 NCF 20A plug for high-current devices standard length: 1.8 m


THIS TEST HAS BEEN PROVIDED UNDER THE GUIDELINES adopted by the Association of International Audiophile Publications, an international audio press association concerned with ethical and professional standards in our industry; HIGH FIDELITY is a founding member. You can find more about the association and its constituent titles → HERE .