PREMIERE

⌈ PRO AUDIO BONO is a Polish audio company specializing in anti-vibration products - feet, platforms, stands and racks. Unlike most companies of this type, it has developed its own solutions, certified by a relevant patent (P.223047). The company was founded in 2010, so this year we celebrate its 10th birthday. ⌋

o much has already been written about anti-vibration systems that improve the operation of audio devices placed on them that we can consider them being full-fledged, often even equivalent with all others elements of the system. If you don’t agree, it may mean that there is still a long, but fantastic way ahead of you to discover this sphere of complex audio world. Unless you just don’t care, then nothing I’ll write will matter for you anyway. Maybe naively, but I assume that those who read "High Fidelity" want to learn something.

I have been using anti-vibration feet, platforms and racks in my reference system for years, actually from the very beginning, since I bought the first serious CD player. It turned out that in the case of sound sources the improvement offered by good anti-vibration systems was then the largest. And it was about both analogue sources, i.e. turntables, and digital sources, i.e. SACD and CD players, and more recently - file players. Over time, it turned out that all the other components in an audio system benefit from it, even power strips and routers. And most of all devices equipped with switching power supplies and / or amplifiers working in class D. And who would have thought that?!

Products for controlling and reducing vibrations are divided into several classes, depending on the chosen method of decoupling two planes, and there are a lot of them. In my system, I use almost exclusively two methods, because they give me the greatest improvement: pneumatic and "rigid" decoupling, using intermediate components with low compliance or rolling bearings. And only in the Finite Elemente Pagode Edition rack I have several joints using horizontally mounted spikes - in the two upper shelves. If there was such a possibility, I would give up on them.

Acoustic Revive RAF-48H anti-vibration platforms provide pneumatic decoupling in my system. They are already quite old, but are still doing great job. In turn, rigid decoupling is provided by the Acoustic Revive RST-38H platforms, used under the speakers and power strip, and RT-38H under the SPEC Real-Sound Processor RSP-AZ9EX filters. And there are also bearings - in the form of a ball bearings featured in the Franc Audio Accessories Ceramic Disc Classic feet used under the SACD player as well as my preamplifier and Finite Elemente large feet under the their rack.

| PAB AND ANTI-VIBRATION FEET

I have been following the development of the Polish company PRO AUDIO BONO for years with interest. They proposed slightly different solutions, but going in the direction, which I consider right, because their anti-vibration feet are based on a ball bearing. Except that it is different from other, mentioned by me producers.

In company materials it reads that they work differently than the solution patented by the American company Symposium, as well as derivative solutions in which "the equipment stands on the ball, pressing on it and increasing friction, thereby reducing its anti-vibration capabilities." And next:

In my foot the device "hangs" on ceramic ball bearings. As a result, he exerts much less pressure on them. Therefore, the ball bearing has much greater mobility and the possibility of converting mechanical energy of vibration into heat. It should be added that the bearing I use has many more balls than [other company's] feet: it is a self-aligning (swinging) bearing with 18-20 balls.

Pro Audio Bono began to manufacture anti-vibration feet along with the production of anti-vibration racks with under-hung shelves. According to Mr. Władysław Skrzypczak, the founder and designer of the PAB, during tests he established that the racks have much better anti-vibration properties when placed on solid metal legs. Initially, the company offered only legs of solid metal and later also feet on rolling elements. The feet on rolling elements are - let's add - the original Pro Audio Bono design, patented at the Patent Office of the Republic of Poland (P.223047)

At the end of March 2015, on the fifth anniversary, the company introduced new anti-vibration feet PAB ceramic 5. Unlike feet manufactured so far featuring steel rolling bearings, the new product used swinging ceramic bearings in which both balls and and the rings are made of very hard sinters - zirconium dioxide, silicon nitride or tungsten carbide.

Elements made from these sinters have a hardness of a dozen or even several dozen times greater than steel, and at the same time are lighter than it. As a result, bearings made of them have - as Mr. Władysław says - incomparably better rolling parameters and longer durability. Ceramic rolling bearings also do not require lubrication, and if they are covered - also cleaning. In PAB ceramic 5 feet, bearing housings were made of monel, i.e. a nickel-copper alloy with an admixture of titanium, cobalt and chromium.

Further tests have proved that "for the production of high-end anti-vibration devices the best are: non-magnetic stainless steel, monel and brass, and the worst - aluminum and lignofol (these materials tend to contour the sound too much, "slim down" the bass and sharpen treble)." Based on this research, PAB began to produce next generations of alloys only from AIF 316 L stainless steel, also used in the chemical industry.

Of the group of steel feet with ceramic bearings, the highest rated were the developed two years later PAB ceramic 7 SN ('7' - seventh anniversary of the foundation of Pro Audio Bono; 'SN' - an acronym of silicon nitride; review HERE). They are made of AIF 316 L stainless steel, containing more than 62% iron, 18% chromium, 15% nickel and 3% molybdenum. Self-aligning silicon nitride bearings are used in them, which is one of the hardest ceramic sinters used in the production of rolling bearings.

These bearings, as we read in the company materials, have better anti-vibration properties than zirconia bearings. Their higher hardness implies less friction. Except for making these footers accurately on CNC machines, all of their design details are the same as those of the other Pro Audio Bono feet manufactured for 10 years. Model 7 SN is still in production. The company also offers PAB ceramic 8 CT feet ('8' - the eighth PAB anniversary, 'CT' - an acronym for carbide tungsten; review HERE), which are structurally different from 7 SN only in the silicon nitride bearing mounted in them. They also replaced the original balls with tungsten carbide balls.

| PAB ceramic 80 SN

The new feet, called PAB ceramic 80 SN, from the technical standpoint are a continuation of the previous designs of this company. There are two elements decoupled from each other - a selected component is placed on top of the upper element. These elements are made of steel, and the decoupling element is a roller bearing with ceramic balls.

The dimensions of the feet are new - they have a diameter of 80 mm and are 41 mm high. The bearing has the same diameter as in the '7' and '8' series feet. An Allen pin is screwed in from above, used to screw the feet to the bottom of a selected device (or speakers). Instead, the device can be simply placed on them - a nut is screwed onto the pin, with which the feet become 53 mm high - the device then rests on the nut. Mr. Władysław Skrzypczak will explain details himself.

WŁADYSŁAW SKRZYPCZAK
Owner, designer

The need to launch a massive steel foot was suggested to us by Sylwester, a well-known music lover and audiophile from Poznań. We were convinced by his arguments that many electronics companies are already equipping their "high-end" products with feet with very large diameters. So we agreed with Mr. Sylwester that an 80mm diameter steel foot with ceramic bearing would be optimal, which in common opinion is best combined with alloy steel, and therefore we chose silicon nitride bearing. That’s how the PAB ceramic 80 SN came to be.

The PAB ceramic 80 SN foot weighs as much as 1850 grams (1.85 kg), which is over four times more than the 7 SN foot. Its height without counter-nut is 41 mm, and with it - 53 mm. The nut, like the footer, has a diameter of 80 mm and is added to each footer. The foot can therefore be used without the nut, by simply placing it under the device, or with it, further increasing foot’s weight. Basically, however, the nut is designed to stiffen the thread clearance in the foot screwed to the device. To make the screwing easier, we add to the foot-nut set a clever brass adapter with a M10/M8 2-thread brass pin, allowing the foot to be screwed with the original screw from the foot of a chosen device (see photo).

The PAB ceramic 80 SN feet can be placed directly under the devices (screwed to the devices), but can also be used as feet for creating anti-vibration platforms using shelves made of plywood, acrylic, MDF or Mylar. The choice of material for such a platform should be preceded by testing these materials with feet in one’s own system. We prefer plywood and Mylar - one can loan them together with the feet for testing.

 Since the beginning of this year, all Pro Audio Bono products bear serial numbers, which are entered along with the device description into the company's database. This allows one to check all the properties of a particular product at any time, which is of paramount importance for any necessary repair. Soon this data will be available on the proaudiobono.pl. ♦

| HOW WE LISTENED TO IT

I always test anti-vibration feet in my system in the same way - placed under a signal source. For several years, this is the Ayon Audio CD-35 HF Edition SACD player (№ 1/50). I always compare the tested feet to the same reference point - for years they have been Franc Audio Accessories Ceramic Disc Classic feet, which was the first product in this company's history; I have one of the absolutely first units.

Their special, white varnished version is permanently screwed into the player, and the preamplifier stands on three feet finished in a classic, black anode, to which I added the RIQ-5010. These are rock crystal discs offered by the Japanese company Acoustic Revive, on which I put washers of the same company, made of piezoelectric material (developed by the University of Tokyo). This is my base which I know best. As an „external” reference I also use Finite Elemente Cerabase Classic feet – one of audio industry’s standards.

Because (four) feet in my player are screwed in, it is difficult to compare them with free-standing feet, such as the ones in the test. I unscrew them and put the player on three feet - in exactly the same arrangement as under the preamplifier. I chose their arrangement years ago that I have one on the front and two on the back. The comparison consists of listening to the same tracks fragments (1 min. long)using the reference feet and then moving the player onto tested feet.

During the test I am moving the SACD player so its connections must be more flexible than the ones I use every day - and I use Siltech Triple Crown cables. So for feet tests (all of them) I replace them with much more flexible, also high-quality, Crystal Cable and Harmonix cables: Absolute Dream (RCA interconnect) and X-DC350M2R Improved-Version (AC power cable).

Recordings used for the test (a selection)

• Cal Tjader-Stan Getz Sextet, Cal Tjader-Stan Getz Sextet, Fantasy/First Impression Music | Lasting Impression Music LIM UHD 061, „Limited Edition | First 2000 Pressings”, „UltraHD 32-Bit PureFlection”, CD (1958/2008)
• Chet Baker, It could happen to you, Riverside/ZYX Music OJC20 303-2, „Original Jazz Classics”, Super Bit Mapping CD (1958/1987)
• Ella Fitzgerald & Louis Armstrong, Ella and Louis, Verve/First Impression Music | Lasting Impression Music LIM UHD 045, „UltraHD 32-Bit”, CD (1956/2010)
• Ferit Odman, Dameronia with Strings, Equinox Music & Entertainment/Master Music XRCD24-NT019, XRCD24 (2015/2016)
• Laurie Anderson, Big Science, Nonesuch 79988-5, „Expanded and Remastered for the 25th Anniversary”, CD (1982/2007)
• Radiohead, OK Computer. OKNOTOK Edition, XL Recordings/Beat Records XLCDJP868, 2 x Ultimate HiQuality CD (1997/2017)
• Radiohead, The King of Limbs, Ticker Tape Ltd. TICK-001CDJ, Blu-spec CD (2011)
• Sonny Rollins, A Night At The “Village Vanguard”, Blue Note/Universal Music LLC UCGQ-9011, SHM-SACD (1957/2017)

I sat in front of the computer for a long time wondering what I should write first. Why? - The "opening" sentence often "sets up" the entire test and is a sort of calibrator. And, to tell you the truth, I still don't know. So I'll give it to you straight - these are excellent feet. What’s more - ones of the best anti-vibration feet I've ever had. And one more thing - these are feet that perfectly harmonized with my player and my system, emphasizing its advantages.

Their impact of the performance is extremely sophisticated. Because the device placed on them gains in terms of refinement, even if it previously seemed to us that there was nothing lacking in this respect - as in my case. They bring internal peace to the sound, ordering events, presenting them in a vivid and resolving way. They lead the sound towards filling, but at the same time towards dynamics, timbre and spatial differentiation. It's a really great product.

Resolution seems to be the most important quality in all of this. In direct comparison with Franc Audio Accessories feet, which are feet that I know, like and value, they seem less expansive. In previous comparisons, the FAA have always, if I remember correctly, presented themselves as the more "fleshy", delivering a richer and internally denser sound. For me it was equivalent of a better sound. The PAB ceramic 80 SN, for the first time showed me what it actually consists of, "stripped" the sound of FAA feet to prime factors.

They were the first in my system that drew my attention to the fact that the excellent feet prepared by Paweł Skulimowski have something in the sound that slightly hardens the attack. I've never heard it before, but this time it was clear and repetitive, recording by recording. And when compared with other products of this type - it disappeared. Because they are - after all - fantastic feet and I have a very good opinion about them. The Pro Audio Bono feet, on the other hand, offer a smooth, refined sound with everything you need, there is also attack, details and subtleties, but it is all well-ordered, resulting in a smoother, but not calmed down, just better differentiated sound.

PAB ceramic 80 SN let air into the sound, slightly moving the foreground bit further away. Only that moving it away does not mean withdrawal. It is about showing a perspective - and this is something completely different. That’s what happened with both. the album of the Ella Fitzgerald & Louis Armstrong duo entitled Ella and Louis, and with the vocal creating an amazing atmosphere in the song Exit Music (For a Film) from the OK Computer album by the Radiohead. So they do not divide the recordings into "better" and "worse" ones, but introduce the modifications in question to the sound of all discs.

The panorama of recordings is remarkable. The foreground is still where it is needed, i.e. with some discs close - see Radiohead - and with others further away, like with Laurie Anderson and Big Science. In addition, it changes from disc to disc, which confirms the good differentiation that these feet offer. The foreground, however, is not pushed away, as it usually happens in my system with products of this type, maybe except for the FAA feet. The PAB ceramic 80 SN do something else - they deepen the stage, making the panorama richer, more interesting.

The tonality that the tested feet propose is also unique. It is primarily refined, because it is smooth and resolving at the same time. The sound is even less aggressive than with reference feet. "Aggressive" may be a bad term, because neither Ceramic Disc Classic of the Polish company, nor the German Ceramic Classic are "aggressive", this is the last thing I would say about them. But the PABs give the treble in an even smoother way - without warming and withdrawing them. Vocals by Ella Fitzgerald, Louis Armstrong, drum cymbals on the Cal Tjader-Stan Getz Sextet, Chet Baker's trumpet from the It could happen to you were even smoother, even more pleasant. It is important because in terms of sonority, the reissue of the Cal Tjader-Stan Getz Sextet in the PureFlection technique is unique.

| PureFlection CD

PureFlection (short for Pure Reflection) is the name used by First Impression Music and we will find it on several reissue series from 2005-2006, 2008 and 2011 and 2014. The founder of FIM, Mr. Winston Ma, was the first a person I know who talked loudly about what many publishers do not want to hear to this day: the material brought to the label, whether in the form of a CD-R or in the form of files, is different from the one we get from a pressed CD ; unfortunately to the disadvantage of the latter. That is why some of his titles were available in several versions; more information HERE.

What's more, whenever a solution appeared that could improve the sound - he tested it and implemented the best ones. This was also the case with the PureFlection technique. In short, it is a set of activities aimed at the best preparation of a glass matrix for pressing discs. Especially for this task, FIM hired an engineer responsible only for its implementation for each new title. In the case of the PureFlection, a process was used to thermally make matrices for Blu-ray discs, which resulted in precise, smooth pits.

The engineer making this matrix for FIM paid special attention to ensuring optimal track width and cared for the right distance between successive tracks in a spiral containing pits - in order to reduce the noise generated by the servo of the optical system when cutting the master from adjacent tracks. As it reads, this translates into better crosstalk parameters (Cross Talk XT), i.e. less optical servo noise when read.

The next step was meticulous execution of extensive tests required by the CD standard specification. Together with PureFlection CDs we get a booklet with a full spectrum of measurements for a given disc, divided into the following categories:

• BLER (17 elements),
• BERL (9 elements),
• fizyczne (6 elements),
• jitter (6 elements),
• E22 and BLER charts.

Let's add that also Sony released the PureFlection CD series in 2014 - for example, Kind of Blue by Miles Davis. And so it was just another step away from Sony's own Blu-spec solution, in the latest form - BSCD2, which from the technical standpoint are almost identical to PureFlection.

A center of gravity, which is something more general, results from the way the PAB ceramic 80 SN displays timbre. This is the first product of this company that sounds really low in my system. It may not be such a strong impression that Franc Audio Accessories feet propose, I have not heard a product that would beat them in this regard, but it didn't bother me with PABs at all, it didn't matter. And this is because the tonal balance they provide is very good, and in addition the bass is better controlled and more selective than with the FAA.

The company's previous feet also had it, but the balance was set higher in them. In all other respects they were really great and in many systems they could have been a better choice than FAA feet. The latest PAB product is different - it sounds dense, low and full. At the same time, it offers a very good definition of sounds. Even Finite Elemente feet, in this respect really good, could not match them in this aspect of the sound.

| SUMMARY

It's nice to see how the Polish companies are developing. We have many excellent producers in our country, many of which are present on the international market. The Pro Audio Bono is also a company of this caliber. With the PAB ceramic 80 SN feet it enters the territories previously reserved for the products of the most famous companies of this type, at least because of their size. Their sound is of the highest quality, reminding me of the sound of the best SHM-SACD discs, bringing to mind Tom Ford Oud Wood or Venetian Bergamote perfumes. It's about refinement and smoothness that leave a taste for a long, long time. ■