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Acoustic Revive RTS-30 and RKI-5005 Turntable Sheets and Anti-vibration Pads

11-18-2021 | By Wojciech Pacuła | Issue 118


Acoustic revive is a Japanese company founded in 1997 and run by Mr. Ken Ishiguro-san. It specializes in connection cables and anti-vibration products, but offers also  innovative products, the ideas of which are most often sourced from the University of Tokyo. We test its products containing a mineral called Kiyoh-stone. The use of minerals in electronic devices has a long tradition. Although audiophiles think that we are the center of the universe, we actually just collect "crumbs" from the world's great tables, that is, the medical, defense and telecommunications industries.

On the other hand, it is a good thing that someone has paid for their development earlier. These are extremely costly solutions because the research that leads to them costs a lot. In audio, we get them—in the right context, of course—for free. The real trick, however, is not to take what the, say, telecommunications industry has worked out, repackage and sell it, because it never works. This is just the starting point. More important is how the solution will be adapted to the music playback devices. Therefore, visionaries, such as Mr. Ken Ishiguro-san, the owner of Acoustic revive, build something new by selecting, changing, trying, listening.


Anyway, the use of minerals to minimize RF noise and EM interference, to convert vibration to heat, etc. is one of the well-recognized methods. Mr. Ishiguro has been using them for years, he was one of the pioneers using them in audio, so he has a lot of experience but also a good intuition. So when he sent me the information that he was introducing a new element into his products, the mineral called Kiyoh, I was sure that it was a deliberate choice.

Let me remind you that so far we have tested all the products in which it was used:

  • RWL-3 ABSOLUTE acoustic panels HERE
  • RPC-1K passive AC filter HERE
  • RCI-3HK (micro-test) cables supports HERE
  • RGC-024K ground conditioner HERE

Although in each of these tests we talked about the materials used in the production of these accessories, it is impossible not to do it again.

Same as in the previous products that we have just mentioned, the 'Kiyoh-stone' was used in the RST-30 turntable mat and the RKI-5005 foot pads. Elia Hontai-san from Muson, a representative of Acoustic revive outside of Japan, says that Kiyoh-stone is a rare earth element whose main ingredient is aluminum silicate. It is available only in one location in the Land of the Rising Sun, in Gunma Prefecture. As he says, this is no coincidence, because Acoustic revive is located in the same prefecture.

The property of this material, which Mr. Ishiguro-san was keen on, is that it easily generates high intensity negative ions, the maximum of which is present in the far-infrared rays. Kiyoh-stone generates up to 40 times more ions than tourmaline. Elia adds that it is one of the more expensive materials of this type available on the market, and only in limited quantities. What's more, in both new products we can also find tourmaline, previously used by Acoustic revive—it also releases negative ions. It is a crystalline boron-silicate material, belonging to the group of silicates, made of such elements as aluminum, iron, magnesium, sodium, lithium and potassium and classified as semi-precious stones.

The manufacturer's website presents this combination in the RTS-30 mat this way:

[…] the blend of natural ore generates strong negative ions, which prevents the generation of static electricity during record playback and exerts a surface activation effect on vinyl records, resulting in an overwhelmingly improved S/N ratio. It realizes a fresh and smooth tone and texture full of energy, and a realistic and vivid three-dimensional sound image localization.

The owner of the Acoustic revive does not want to reveal more technical details about the composition of the RTS-30 and RKI-5005, because his capital is the work he did finding the right materials and selecting their proportions, and this is easy to copy (steal). In any case, both products look absolutely professional and could be offered by companies like Apple. They are in the form of relatively thick elements resembling silicone mats from the 1950s and 1960s to the touch. And indeed—the base material is gray silicone.

The mat and pads are flat on the underside only. There is a three-dimensional pattern on top of them. When we look at it, it turns out that it resembles the pattern one finds on the RGC-024K ground conditioner and it is not accidental. The already mentioned Elia Hontai explained it to me in the email, using the example of the washers:

We can use this insulator for almost any application: under any device, power strip, stand, cable, combined with other insulators or platforms. Note the geometric pattern on the top—please use them this way. Mr. Ken Ishiguro says that if the pattern is at the bottom, the impact on the sound will decrease by 50%.

As it turns out, this pattern is not accidental, but was calculated to maximize the effect of negative ions on static electricity. And there is something to it, because using different records with the RTS-30 mat, the electrostatic attraction that the records usually exhibit was absolutely minimal. In turn, with the classic felt mat, it was relatively large. Elia-san points out to one more thing—the RKI-5005 pads can be used not only under the devices, but also on them.

The RTS-30 is a turntable mat, i.e. an element that mechanically (being a mechanical bridge) coupling a record (LP) and a turntable. It has a diameter of ø 290 mm, so it is slightly smaller than a record (ø 300 mm) and is relatively thick—5 mm; weighs quite a lot—355 g. RKI-5005 washers are the of same thickness, but their diameter is smaller and amounts to 50 mm. This is an absolute coincidence, but the Pro-Ject turntable feet and the Finite Elemente Cerabase Compact anti-vibration feet have exactly the same diameter.



The RTS-30 turntable mat and the RKI-5005 foot pads by Acoustic revive have been tested in the High Fidelity reference system. I used an inexpensive but excellent Pro-ject Debut Pro turntable with feet from another model from this manufacturer. I assumed that if the changes with it were not legible or ambiguous, I would choose a more expensive design. As it turned out, the turntable placed on the VinylSpot.pl All You Need platform showed without any problems what the tested mat is and what it is not. The difference between it and the felt pad with which the turntable comes to us was huge.

For the test, I chose five different types of records—both in terms of music and the way they were pressed. I started with a low weight, quite flexible disc with archival recordings from the 1940s. We deal here with crackles both from the original shellac record, as well as the crackles and noises of the vinyl itself. The next one was slightly thicker, but it was still a classic re-issue from the early 1980s. The next album weighed 140 g, but was prepared in a modern way, from ultra-clean vinyl. Finally, the last two were pressed on heavy vinyl—180 and 200 g respectively; the latter version has only been pressed on one side of the record to prevent modulation of the grooves on the other side.

To better understand the operation of the RTS-30, I compared it with two other specialized mats—a German mat made of cork and rubber, by a company led by our compatriot, the Pathe Wings, and an excellent Hungarian mat called Hexmat Yellow Bird (HERE). All three are significantly better than the classic felt mats with which we get inexpensive turntables. But the RTS-30 also turned out to be the best of them.

I also tried the RKI-5005 feet supports, placing the aforementioned Pro-Ject turntable on them. Its feet had exactly the same diameter as the washers, thanks to which the turntable was very stable on them and looked good. To confirm my observations, I also tried them under the Finite Elemente Cerabase Compact feet, used under AYON Audio Spheris III tube preamplifier.

Recordings used for the test

  • Tommy Dorsey and Frank Sinatra, The Dorsey/Sinatra Sessions Vol. 2 (July 17, 1940 - May 28, 1941), RCA Records CPL2-4335, 2 x LP (1982).
  • Alan Parsons Project, Eye In The Sky, Arista Records AL9599, LP (1982), from: Alan Parsons Project, The Complete Audio Guide to Alan Parsons Project, Arista Records SP 140, Box: 8 x LP (1982).
  • Dean Can Dance, Into The Labyrinth, 4AD/Mobile Fidelity MoFi-2-001, Silver Line Special Limited Edition | No. 1545, 2 x 140 g LP (1993/2010).
  • The Montgomery Brothers, Groove Yard, Riverside/Analogue Productions AJAZ 9362, Top 100 Fantasy 45 Series, 45 rpm, 2 x 180 g LP (1961/?).
  • Count Basie & Tony Bennett, Basie/Bennett, Roulette/Classic Records SR 25 072, 45 rpm series, 4 x Special One-Sided Pressing, 200 g LP (1959/2006).

At first, the RTS-30 turntable mat is remarkably similar to a product that could be pulled out of a dusty drawer where it would have hidden since the 1950s. Although it is a child of the 21st century, with its inventions regarding the materials from which it was made. And yet we are dealing with a turntable mat, which does not so much "change the sound," because it does not do it, but "prepares" it, so we perceive the music more directly, on a deeper level.

Tommy Dorsey & Frank Sinatra The first album I reached for was the re-edition of sessions, released in 1982, which Frank Sinatra recorded in 1940-1941 with Tommy Dorsey's band, entitled The Dorsey / Sinatra Sessions Vol 2 (July 17, 1940 - May 28, 1941). In the same year, the project received a Grammy award in the "Best Historical Album" category. The LP was pressed on ordinary vinyl, probably obtained from the secondary grinding of older records. Its problem is that the sound has been subjected to process turning mono recording into a stereo one—blah... . Despite this flaw, it is an album that is musically delightful and sonically surprisingly good.

The sound with the inexpensive Pro-Ject turntable with its classic felt mat was good, really good! The RTS-30, however, brought an absolutely new quality to its sound. The pop & cracks that come from playing 78 RPM discs was much less audible with it. This means that fast impulses with a narrow bandwidth but high slew rate—and that is what cracks are—were very well damped. Traditionally, this is the domain of mass-loader turntables that dampen such impulses—or should dampen—thanks to the large mass of the platter and base.

Meanwhile, with the Acoustic revive mat the distortions in question were still audible, but hidden beyond the sounds of the instruments and beyond Sinatra's voice. The following songs had their own character—they were ripped from records of different quality—and yet they sounded extremely smooth, I had no doubt that they were recorded in the same place by the same crew, often one after the other. What's more, adding the mat improved differentiation—even annoying spatial effects, consisting in adding a phase-shifted frequency segment to the base sound, usually to emphasize the sound of one of the instruments or their group. It should have been more annoying, and yet it wasn't.


Acoustic revive RKI-5005

The RKI-5005 Anti-Vibration Pads, which look like a scaled-down copy of the RTS-30 turntable mat refine the sound. This seems to be the most important change that I heard after placing them under the three feet of the Pro-Ject Debut Proturntable. Although the improvement they introduce when going from A → B, i.e. from the sound of the turntable without them to the sound with them, you can hear their influence even better when you take them out (B→A ).

It will turn out then that the RKI-5005 bring refinement and calmness to the sound, in a very similar way to the aforementioned mat. The differences in this case are perhaps not that big, but considering the price of the pads, it's hard not to notice that this is the cheapest way to improve the sound of any audio product equipped with feet. For years, many years I have been using CP-4 washers from that company, actually under every device, but what the new discs offer is much more tangible and meaningful.

The sound is slightly lower and deeper with them. The treble seems slightly stronger, but this is rather due to their better definition, not emphasis. As I say—the changes are so clear and so consistent with the sound of the system that it is hard to imagine that someone would not even try them out. I am sure that after such a test you will feel obliged to buy a few more sets—our audio systems really need it ... . 

Price: 89 EUR (+VAT)/4 pieces.

Alan Parsons Project however, let's come back to the mat. The better separation of the instruments, which we have just mentioned, was in absolute agreement with the fact that the sound with the Acoustic revive mat was deeper, more three-dimensional and less nervous. Although there were more details and subtleties in the presentation, the sound was darker and calmer. This was perfectly demonstrated by the Alan Parsons Project's Eye In The Sky, or rather its re-edition from 1982, coming from the The Complete Audio Guide to Alan Parsons Project box. It was released on a classic, quite thin vinyl, but it sounds really great.

Thanks to the mat, I could hear the echoes behind the percussion better. As a result, the whole percussion gained in vividness and depth. Although it seemed softer, more silky than with an ordinary felt mat, but also with mats to which the Acoustic revive was compared. It was similar with the vocals of Eric Woolfson, the author of lyrics and music, not only singing, but also playing the Wurlitzer electric piano here. It had a smoother attack and the whole "flowed" better. It was a much richer, better experience than with a regular mat.

This seemingly small change brought more to the sound than I expected and assumed. Although it is difficult to talk about "correction," because unlike other turntable mats, the individual aspects of the sound did not change, the sum of minor shifts of accents, a significant deepening of the "blackness" behind the sounds and—the resulting better resolution—turned listening to the record into a new experience, I felt almost as if I listened to it for the first time.

Dean Can Dance It introduced yet another benefit. Spatial relations, previously really good - for a turntable of this class—resembled those of more expensive designs. The sound of synthesizers from the Into The Labyrinth by the Dean Can Dance duo, released on 140-gram vinyl, perfectly cut from digital files by Mobile Fidelity, had a much bigger "halo" around them with the Acoustic revive mat. The space did not expand in any distinct way, neither in depth nor in width, and yet the sounds somehow "expanded," were not compressed to such an extent as without the AR mat.

The Montgomery Brothers The deepening of the sound that I am talking about also resulted in higher dynamics. It was not, however, dynamics as in "louder" style, but rather something like "more." As if the presentation was wider and more colorful.

What I am talking about came out really clearly with a heavy 200 g vinyl, The Montgomery Brothers' Groove Yard, pressed at 45 RPM. It sounded denser, stronger, clearer. It had a softer attack, gentler decay and much, really, nicer sound. I had no doubts that the addition of the Acoustic revive mat—this is how I go back to the beginning—"adapted" its sound in a similar way to the VinylSpot.pl All You Need anti-vibration platform, on which the Pro-Ject turntable stood (you'll find more about the platform HERE).

Count Basie & Tony Bennett Listening to music from heavy vinyl, pressed on one side of the record only, and it was Count Basie and Tony Bennett's album, entitled Basie/Bennett, re-released by Classic Records ("45 RPM series, 4 x Special One -Sided Pressing, 200 g LP ”), I got the same, slightly distorted "s" in the Bennett's voice, the same, slightly emphasized wind instruments attack as with a regular mat. And yet it was a much more comfortable reproduction, a reproduction that sounded like one form an expensive turntable. Yes, the Acoustic revive RTS-30 mat is really that good, and the RKI-5005 washers are even better.


Each record, with better and better pressing quality and on better and better musical materials, showed a significant improvement in sound, an improvement not so much 'significant', but really important. Better differentiation and resolution, higher dynamics, better space presentation—all this was present with each record. This resulted in a beautiful, smooth, soft and natural sound.

An equally important, perhaps even more important change has to do with pops & cracks and stylus travel noise. These distortions, resulting directly from the mechanical nature of pressing and playing LPs, are inherent to the love for the black records and cannot be completely eliminated. However, you can strive for it. The RTS-30, the mat in question, does it in an excellent way for little money. It will offer an improvement in this area with both inexpensive, light turntables and heavy machines, which theoretically should be resistant to it.

Moreover, the tested turntable mat does not change the sound in the way that other mats do. Although the noise is lower with it, although the cymbals are clearer, and the reverbs are longer, this is the result of extracting something from the sound that was already there, and not adding something new.

So both elements, like other Acoustic revive accessories from 'Kiyoh-stone' series, remain in the editorial office as part of the reference system equipment.



Price (when reviewed): 380 EUR (+ VAT)

Contact: YOSHI HONTAI | MuSon Project, Inc.


Provided for test by: MUSON PROJECT


Translation: Marek Dyba

Images: Wojciech Pacuła

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