⌈ Anti-vibration feet belong to the basic equipment of every device, loudspeaker and even devices used for power supply. Historically, they were treated as the so-called "accessories", today they are often an equivalent element of a system, because they model the sound of audio products placed on them. The best are able to upgrade the sound of a given product to a higher class. We test the first ever anti-vibration feet in the history of Divine Acoustics called KEPLER. ⌋

ivine Acoustics is a specialist company focusing on loudspeakers. Its designs are unique, both in terms of shape and solutions used. And in addition they sound great. An introduction to the lineup of a specialist company of other than "basic" products - in this case, these will be loudspeakers - is most often associated with the desire to diversify the offer and simply adding to revenue stream. And that's fine, that's how all companies in the world operate, including the audio industry.

But in addition it is good if there is something else behind the product - something that enriches this company. Divine Acoustics firstly introducing the Halley, and now the Kepler anti-vibration feet will inevitably raise questions about motives. The fact that the financial thread is present here is probably clear as for the company to grow it needs to make money. In the case of Mr. Piotr Gałkowski, the owner and designer of the company, however, it goes hand in hand with the need for development.

Evidence? - Let us ask ourselves what speaker cables fully implement the vision of the loudspeakers' designer, and the answer is: the same ones that are used inside speakers, that is, the best solution is to use the same wires inside loudspeakers and then from speakers terminals to amplifier. And this is the genesis of Halley cables, flat ribbons being an extension of the internal cabling of the Electra Generation 3.

So let's ask a second question - what should one put the speakers on. They can be decoupled using a ball bearing. That's what Finite Elemente does, Pro Audio Bono, Franc Audio Accessories, and Stacore anti-vibration platforms work on a similar principle and also Avatar Audio.

The most common choice are spikes though. This is a simple, highly effective way to reduce vibrations and for their directed extinguishing, though imperfect one. To make it work, the spike itself is not enough, it must be a whole, complex system, as in the Stillpoints feet. Or in Keplers.

| KEPLER

Mr. Gałkowski's solution seems to have much to do with both of these solutions, especially with the latter. But it is also so different that it is not a duplication of a technical solution of any of the aforementioned manufacturers.

The Kepler feet come in nice, neat boxes with a set of three, four or eight of them. They were designed for loudspeakers, but it soon turned out that they work well under electronic devices. These two versions - the loudspeakers feet feature the "S" suffix - differ in the number of decoupling stones used, and thus the maximum load, which for the electronics version is 20 kg per foot.

They look unbelievably professional, simply professional. Each feet consists of more than 40 (!) elements, and – according to the manufacturer - their main function, ie the accumulation and dissipation of vibrations, is carried out through nine layers made of various materials. In the center of the whole design lays, however, the CeraGem technology developed by Divine Acoustics. As it reads in the manufacturer's materials, it combines the advantages of hard materials: sintered ceramic, precious stones with a repeatable crystal structure and various metals. CeraGem technology is a proprietary solution of the company and does not duplicate solutions used by other companies:

Inside the Kepler enclosure, a rectangular ceramic bar cooperates with precious stones arranged in the shape of a pyramid based on a non-parallel triangle. The stones are held in a fixed position, they cooperate with chromium-nickel steel and together they form a three-layer system.

The pyramid rests directly on the ceramic bar, and the system is encapsulated with other elements that gently compress the whole system and create a kind of heat sink that converts the cumulated energy into heat.

The top threaded spindle transmits vibrations from the device or loudspeaker directly to the top of the pyramid. The steel and chrome, nickel, copper, titanium, molybdenum, aluminum, carbon and auxiliary elements made of wood and polyamide were also used in the design of Kepler in individual layers.

source: company's materials

From the outside one can see six layers of different materials in black or steel color. The whole is bolted from below – with six screws - and from above – with three. The feet have an irregular shape resembling a knob in the machine tool. From the top you can see engraved inscriptions with: company's name, model and CeraGem technology. The feet have an outer diameter of ø 60 mm and a height (with nut) of 35 mm. The nut on the upper part of the screw is used for easier placement under the devices. The version for the speakers is screwed into the holes in the base - the standard spindle thread is M8, but on request you can get others.

Keplers require a bit more work during assembly than other feet, due to the different design. The point is that when screwing in and assembling, the pin is locked with the lock nut, which later should be released. It's not difficult to do, but you have to remember the right sequence of actions. It is important that after leveling the speakers or electronics, the stem has a slight play, and it is not stiffened.

The feet are offered in sets of 3 or 4 pieces with interchangeable threads as feet to be used under audio components and in sets of 8 pieces with fixed mounting threads as a replacement for screw-in speaker spikes.

And one more thing - Keplers come with thin felt discs, you can put them on to avoid damaging the surface. Mr. Gałkowski says that he did not notice that they changed the sound. But it's worth trying something else, like Acoustic Revive CP-4 washers, made of piezoelectric material developed at the University of Tokyo.

PIOTR GAŁKOWSKI
Owner, designer

The Kepler anti-vibration feet were created „by accident”. They were to be part of the newly designed speakers, which will soon be available. Initially, Kepler was meant to suppress the vibrations of the tweeter in a chamber specially prepared for it. During one of the listening sessions, I placed the prototype of this "silencer" as the feet under the whole speaker and that's what started the whole story ...

In this way, an idea for anti-vibration feet for the speakers was born. The ones that would replace the standard spikes and which would not degrade the sound at the same time. A necessary condition to meet was also the small height of the feet, so that the speakers placed on the Keplers would not become taller than on standard spikes. I also wanted to be able to adjust the height and make it as easy as possible - hence the housing features threads and a polygonal adjusting ring, so that it can easily be rotated on the floor. Keplers were also supposed to work on the carpet, because not everyone puts their speakers directly on the floor. I did not want to duplicate other solutions, so I did not use either balls or bearings.

After a few months and after making surely more than 10 prototypes, I gave a few pieces to my friends for evaluation. And they, instead of placing them under the speakers, put their feet under preamplifiers, DACs and transports. And it started again ... A wish list came to me, so that it would sound so and so and that the sopranos would be such and such, and the midrange would be better, and... and.... The prototype number 23 or 25, I am not even sure anymore, was the one chosen for production. It took me about a year to finish the project.

The Keplers are primarily based on a variety of materials that, combined in the right order, provide effective vibration suppression, and thus a change in the sound of the devices we put on them. Finally, there are 9 layers stacked on each other in the right order and with a specific geometry. With this number of layers and material diversity, there are over 350,000 possible combinations, and after rejecting those that are not stable and durable enough, there are still a few thousand to chose from.

At least several hundred of them were evaluated, and one was chosen, which among all others was as neutral and natural sounding as possible. It was not about making feet that, for example, add bass, but at the same time messes with the midrange and high tones, or ones that play smoothly, but at the same time dampens and averages the sound.

A few useful clues:

• new Keplers need around 24 hours under the weight before all the layers settle in,
• I do not recommend using Keplers under other feet, they were designed as replacement and not as a complementary element,
• during assembly and fixing the screws do not use for to avoid introducing strain,
• during the listening tests, I suggest using Keplers not only for the amplifier or player, but also for other devices, such as power strip or conditioner, using Keplers as a base for cables, etc. The key will be finding the configuration that results in the best sound improvement of the whole audio system, not one specific device.

It was an A/B/A comparison with A and B know, using 2 minutes long music tracks. The feet for electronics were used under the Ayon Audio CD-35 HF Edition, where they were compared to Franc Audio Accessories Ceramic Disc Classic with upper elements replaced with Acoustic Revive quartz discs.

The loudspeaker feet were used under Acoustic Revive stands, prepared for me by Mr. Ken Ishiguro of Acoustic Revive. These are complex, multi-element stands that cost as much as the Harbeths 40.1 themselves that are placed on them. These stand grew on me over time but I have never really accepted the feet that came with them. So I removed them and placed stands on OPT-30HG-SC HR by another Japanese company – Audio Replas. And that what I compared Keplers to.

The Kepler feet are not the first anti-vibration product in Mr. Gałkowski's lineup. Let me remind you that we reviewed the Gravity anti-vibration platform. Nevertheless, they seem to me a new beginning, at least when it comes to vibration dampening. It is an excellent product that matches and even surpasses many renown products of this type from other countries.

These feet are excellent in extracting proper articulation of recordings. The point is that they are very resolving, so they bring out a lot of information (saying "resolving" and so on what I really mean is how they change the signal, but I will refer changes directly to them). Once we notice them, we'll hear them every time, as I did, comparing the Keplers with the Franc Audio Accessories Ceramic Disc Classic , the Pro Audio Bono Ceramic SN7 + and the Audio Replas quartz bases.

Player | My reference point was, in this case, the Ceramic Disc Classic, because the Ayon Audio player in its High Fidelity Edition (HF Edition), which is my reference player, comes equipped with them. In the direct comparison, I could hear that using these two sets of feet resulted in a different sound, a slightly different approach to its nature, and yet it was clear to me that it was the same level. That is – a very high one.

The Keplers show a slightly less impressive sound. And this is because they gently push phantom images away from us - that is, from the line connecting speakers. Paweł Skulimowski's Classic Ceramic Discs generate a larger sound image, larger instruments, while bringing them closer to us. And that results in a "wow!" effect, because you do not have to listen to music with them for a long time to say that you like it.

Divine Acoustics feet are different. They offer a more open sound at the top, and yet they sound gentler, they are more delicate in treating musical matter, and yet they go deeper into a recording. They also show a faster attack. This usually does not happen, because if something is more open, faster, more accurate, it usually also more "revealing" – shows all problems with recordings, with system, etc. And here it was different, because it was with them that everything I listened to sounded milder, in a more delicate way – whether it was a slightly bright Ella Fitzgerald's vocal from the album with Cole Porter songs or Nina Simone's from the Silk & Soul.

The effect I mentioned and which Franc Audio Accessories feet charm listener with is based on bringing instruments closer to the listener and enlarging them. The enlargement in this case is supported by the low, slightly flashy bass that these feet offer. After many years trials, I can say that this bass is slightly "puffed up". It was perfectly audible that the Keplers are slightly lighter and their extension in the bottom was not so impressive. But…

This is an important "but" because it makes the tested feet more similar to the Pro Audio Bono's, which deliver a perfectly balanced bass range. Nevertheless, I can say that Mr. Gałkowski's feet show an even better organized and even better defined presentation of the lower part of the band. One can hear „more” with them. I am not saying "better", it is not the point, but there is "more". They are not always as "gutty", but they are always ultra-precise.

Because the Keplers are great in differentiating the distance from the foreground, the way musicians play, the impact. They are extremely fast and clear, making the sound internally richer. Not so impressive or so "charming", but equally refined and internally complex. Due to that they are able to present smaller instruments than other Polish feet, in a similar way as Finite Elemente products do. Differences are not big, but they are related to changes in tonality, which is what makes them important.

Loudspeakers | I performed the tests under the SACD player and the speaker stands separately, but their results were surprisingly convergent. The Harbeths benefited from this change in terms of resolution and differentiation, which they usually miss a little. The sound was also more selective. It could be heard that the attack and the purity of the decay improved. Pat Metheny's guitar, Jarrett's piano from the Köln concert, but also electronics from Rojek and Aquavoice - all sounded faster, more precise and cleaner.

As in any case, also in this one feet modified the sound, changed it. Placed under the speakers showed that the midrange became most important for them. Top and bottom, even at the very extreme frequencies, were colorful, fast, resolving, I doubt anybody could claim that they expected more in those areas. But the attention of the listener will be directed to vocals, guitars, cello, etc.

There is also a subjective element, because I felt like there was less bass and treble in this presentation – because of a stronger emphasis of events in the midrange. Because the lower midrange, responsible for the saturation and size of the instruments, had a smaller share in the whole sound, and the whole seemed a bit lighter than with the quarts I normally use.

Did it make it better? Or maybe worse? Neither and either at the same time. The Keplers are excellent, I have no doubts about it. And just because they present so much information they once again reminded me that audio is an extremely subjective art of choice. We operate within an objective framework, it is quite easy to say what a good sound is and what is not, it is also possible to classify sound and point out which is better and which is worse.

Each of these choices will be made, however, within a certain margin - a margin in which there is room for your own choices. So let's remember that even such a unique product as the Kepler feet is not a remedy for all the bad in your system. In my system, everything improved with them, but the magic that makes all the recordings sound more interesting was partly gone. Simply a differentiation was better and the higher quality recordings sounded better and the lower quality ones sounded even worse.

Summary

The sound with Divine Acoustic feet is delicate, open, accurate and intrinsically complex. It is also extremely resolving - with them expensive components will show more of their class. And all this will be achieved without making the top brighter, on the contrary – there will be a silky coating on everything. The volume of sounds is smaller with them than with the Franc Audio Accessories discs and with the Audio Replas quartz bases, and the bass is not so impressive and dense, although it is more accurate. The whole sound is set a bit higher - slightly, but still - though the treble is milder with them.

However, this is due to the outstanding differentiation and resolution one could built a whole system around. The Keplers will help you extract additional information from recordings, speed up their pulse and present their pace more accurately. And at the same time they represent a fantastic engineering, top quality make&finish on a level that I know only from the products of the Korean company Hi-Fi Stay and extremely interesting, resolving sound. The first feet in the Divine Acoustics lineup immediately go to the pantheon of this type of products. They will be a great alternative for the other top products of this kind.