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Manufacturer: AUDIO UNION
Price (when reviewed): 180 000 PLN

Contact: 2405 NE Cross Creek Ln
Lee’s Summit, MO 64086 | USA


Provided for review by: RCM

trick of a wobbly rack and turntable placed on top of it, which did not even twitch, while the rack wobbled, as if it was about to fall apart, was one of the highlights of this year's High-End Show in Munich (more HERE). Every visitor could approach this product, wobble it personally and than wonder about the solution that made this is possible.

And this is really a really advanced solution. The turntable was in fact integrated with anti-vibration MinusK platform, designed for research laboratories as a support used under electron microscopes and sensitive to external vibrations measuring instruments. A similar pedigree has the Mr. Ken Ishiguro's pneumatic Acoustic Revive RAF-48H platform, used at the University of Tokyo, but in this comparison, it is like a bicycle, and MinusK as high-class Mercedes.

Innovative feature of this solution lies in such decoupling of the element placed on it that the resonance in the horizontal plane equals 1.5 Hz and in the vertical, 0.5 Hz. This is a significant achievement, as it means that they are far below the usable bandwidth. The mechanical, passive system is called Negative-Stiffness Mechanism (NSM), and it uses a solution called the Micro Signal Architecture (MSA), reducing noise and micro-vibrations and it was developed by an American engineer, Mr. Dr. David Platus.

His company MinusK Technology has developed a unique system of mechanical isolation, where the central part rests on a large spring, but in both planes it is supported with thin shanks, which prevent two boards from moving – the upper one, on which the isolated device is placed - and the lower one, which the actual basis. The system is extremely sensitive and needs to be adjusted for a particular load.


His company MinusK Technology has developed a unique system of mechanical isolation, where the central part rests on a large spring, but in both planes it is supported with thin shanks, which prevent two boards from moving – the upper one, on which the isolated device is placed - and the lower one, which the actual basis. The system is extremely sensitive and needs to be adjusted for a particular load.

This is not the first creative manufacturers' group, which included Mark DOHMANN. He is the man who designed the Continuum Audio Labs Caliburn turntable and Cobra tonearm! This turntable has been in Michael Framer's, from the "Stereophile", reference system for years. He is one of the most influential personalities of the analogue world. This realization of this project was possible thanks to the financial support of David Payes, privately analog audio fanatic, who made a fortune on the PC market.


The novelty of the solutions used in this turntable lies in the fact that the MinusK system is permanently integral with it, or in fact it is the turntable that is integrated with the system. The upper board of the system is at the same time a top cover of the turntable, with motor and platter attached to it, and the lower board is integrated with feet. The whole system can be viewed through a large glass window in the front wall. The upper board is made of precision machined aluminum and integrated with the "collar" screening the platter. It seems that it is serving an aesthetic purpose, because he platter consists of several elements of different diameter, which does not make it look good.

It's a thick aluminum latter, to which via sort of separating layer, a lower, wider platter is fixed. It features three layers - aluminum, metal similar to iron and pasted on the top, fairly soft mat. The brass pin is threaded so that a clamp can be screwed on. One needs to be careful not to overdo it – if you tighten it too much that record might warp.

The motor is bolted in an unusual spot – behind the platter and close to its outer edge. We know this solution from Rega turntables, but in the extreme high-end it is rarely used. It seems that it was just in order to best balance MinusK. Driving torque is transmitted from the high aluminum shaft screwed to the motor shaft, to the bottom platter using two, translucent strips of circular cross-section.

Power to the motor is supplied by a large, massive module, resembling a power amplifier in a well-made aluminum housing. It is connected with turntable using two cables – one for power (4-pin XLR) and another for control and feedback signals (Ethernet). The power supply is in fact a complex, microprocessor-controlled digital voltage converter. When we look at the rear panel we can see another socket, that allows software actualization. It turns out that the control has a lot of different modes of action, and each of them results in a different sound! Perhaps manufacturer should let users to select one of them?

The turntable can be fitted with two tonearms attached to the dual modules. Originally they were single, and therefore lower, but Polish distributor, RCM, suggested that they needed to be strengthened – and manufacturer agreed. Usually turntable designers seek for the greatest possible rigidity of the arm (stylus) - platter (record) system. Here it is solved differently. The bases of tonearms are suspended on a heavy element, which is in turn suspended on thick pulls and controlled with magnetic cushion. The compliance of this element has to be determined in each case for particular arm/s.


As you can see, Helix 1 is not just "another" turntable. It is a decoupled design, but also a mass-loader like once Thorens Prestige. Its decoupling system, however, can move not only up and down but also sideways - SME prided itself on the fact that although their turntables were decoupled, they were forced to move only vertically. This was an element distinguishing them from other decks, eg. from Avid, Linn and so on.

This is an a-typical design, so it requires an unusual preparation. I would suggest using the services of a distributor. They will not only assemble the turntable - and this comes in a large, sturdy box - but perform the whole setting and adjusting. MinusK system is very sensitive to changes in pressure, so it's a pity that the manufacturer did not provide users with an indicator that would inform them whether the turntable is in the optimum position (balance).

Another problem might be turning the rotation on. This is done with two buttons - for 33,33 and 45 rpm, glowing green - "ON" - or red - "OFF". The buttons are located on the board, which on the lightest touch moves, bumping inside the base. In my opinion some sort o locking mechanism would come handy - even a very simple one – that would allow to lock MinusK in a given position (maybe even via remote control).

The person installing the turntable will also be obliged to get rid of hum – the power supply is extremely eager to introduce interference. You can overcome this, but a help of an expert will come handy. Anyway, the PSU must be put as far as possible from the turntable. During this test it was placed a bit too close, but it was acceptable. The idea was to put it on anti-vibration platform - please try it with high quality power cables and elements protecting from RF and EMI interference, such as X Block Brown and you will see for yourself how it changes the sound.

Following my own recommendations I did not participate in the process of turntable assembling (on the upper board of Finite Elemente Pagode Edition). It allowed me to study the design and its execution. Distributor delivered it with Frank Schröder's dedicated CB Tonearm and Shelter Accord (13 500 PLN) cartridge – almost the same setup as with TechDAS Air Force Two. CB is a fantastic tonearm with an unusual length of 9.4 ", and its tube is made of carbon fiber.

The rest of system was my usual setup: RCM Audio Sensor Prelude IC phonostage, Ayon Audio Spheris III preamplifier, 710 power amplifier and Harbeth M40.1 loudspeakers placed on stands made by Mr. Ken Ishiguro of Acoustic Revive. The signal between phonostage and preamplifier was transmitted using Siltech Triple Crown IC, and Crystal Cable Absolute Dream was used between preamp and power amp.

Records used for the test (a selection)

  • Brendan Perry, Ark, Cooking Vinyl/Vinyl 180 VIN180LP040, 2 x 180 g LP (2011)
  • Count Basie & Tony Bennett, Basie & Bennett, Roulette/Classic Records SR 25 072, 45 rpm, 4 x one side, 180 g LP
  • Depeche Mode, Ultra, Mute Records DMLP9, 180 g LP (2007/2014)
  • Jean-Michel Jarre, Magnetic Fields, Disques Dreyfus/Polydor Super Pols 1033, LP (1981)
  • Manuel Göttsching/Ashra /Daniele Baldelli, Volcano Extravaganza, The Vinyl Factory VF178, 45 rpm, 180 g LP (2016)
  • Mel Tormé, Oh, You Beautiful Doll, The Trumpets of Jericho - Silver Line, 904333-980, 180 g LP (2000)
  • Omni, Omni, Savitor SVT 021, LP (1985)
  • Oscar Peterson, Exclusively For My Friends, MPS/Edel Germany 59094784, „AAA Reissue Series”, 6 x 180 g LP (1992/2014)
  • Painkiller, Execution Ground, Karlrecords KR025, „Test Pressing”, 2 x 180 g LP (2016)
  • Polish Jazz Quartet, Polish Jazz Quartet, Polskie Nagrania „Muza”/Warner Music Poland 9 59601 4, Polish Jazz | vol. 3, 180 g LP (1965/2016)
  • The Andrzej Trzaskowski Quintet, The Andrzej Trzaskowski Quintet, Polskie Nagrania „Muza”/Warner Music Poland 9 59601 3, Polish Jazz | vol. 4, 180 g LP (1965/2016)
  • Zbigniew Namysłowski, Winobranie, Polskie Nagrania „Muza” SXL 0925, Polish Jazz | vol. 33, LP (1973)
Japanese issues available at

I approached Marek DOHMANN's turntable test with a certain dose of distrust. Apparently on one hand, the designer himself guaranteed a high class of the product and appreciated the idea behind the Helix 1, confirmed by other two, highly respected designer participation in this project, Messrs Frank Schröder and Rumen Atarski, and yet ... Let me put it this way: many smart, accomplished guys in the past came up with something that either turned out not to function well in the real world, or was so technologically ahead of its time that it was impossible to realize the idea exactly as planned. The idea itself is sometimes not enough.

And on top of that there was this irritation, which was growing in me when I was using the turntable – it's quaking during the operation was depressing. And finally, there is this thing that even now, after my conversion to "döhmannizm" bothers me – the turntable's decoupling in all planes was (and still is) for me, contrary to intuition and experience. Because this is one of the features of Avid HiFi turntables, which is raised the supporters of rigid constructions and SME lovers (now also Kronos Audio), that's causing a warming up of the sound and blurring the attack. Plus there is the soft isolation of the tonearm from the platter – a complete heresy.

Although, on the other hand, I could have guessed that there was more to it than just child's curiosity of an engineer who asked "what if ...?" The same goes for Avid turntables, that I really like and that while presenting a certain sonic signature, remain among the most pleasant sounding devices, one of my favorites. If, however, manufacturer used only the original theory, and just decoupling a large mass in all directions, Helix 1 should sound similar to the Avid Reference, right? And maybe even like Kronos Sparta and to some degree as Linn turntables. But in fact it sounds completely different.

I verified my initial expectations to another batch of Polish Jazz reissues. With the first, released a few months earlier, six of these records I assumed that it was only an addition to digital editions (Compact Disc), designed to appeal to young people who have recently bought a turntable and are into vinyl collecting; for true collectors - I thought – new re-issue were unnecessary. I was wrong. Listening and comparing them with the originals and subsequent re-issues proved their high value and made me cautious in my assessments. Ultimately, I had to use a individual approach to each title and each of them could become attractive for both the novice and the experienced vinyl fan.

Another "six" turned out to be even more interesting, mainly due to the stereo (analog) versions of Polish Jazz Quartet and The Andrzej Trzaskowski Quintet (respectively, vol. 3, and vol. 4) albums. Mainly because - I think – the turntable under reviewed was incredibly differentiating device. Differentiation is the ability to show changes in the material, while maintaining its consistency. Only partly it is connected with detail retrieval, because that is associated rather with better selectivity, and it is closer rather to a resolution. Helix 1 in this respect was simply stunning. It showed even little changes between successive pressings of Zbigniew Namysłowski Winobranie (new remaster is coming) in a very firm and solid way, as though it perfectly "knew" how the shape of the grooves tracked by the Shelter's stylus changed and in addition it was able to translate it into language understandable for the listener. Also, any change in the pressing method, in the master (digital or analogue) selection of consecutive releases was perfectly clear.

Which brings us to the place where one should ask oneself how much one cares about the "ruthless" truth, and how much one prefers the "liberating" truth. Contrary to appearances, is not only some logical exersize, or useless theorizing, but rather the question of the basic priorities for any audio fan. I introduce this concept, because the differentiation test turntable leads to acceptance. It is rare in audio, where the focus is mostly on negation, because it pushes us forward, provokes us to search for new, better devices and recordings. But here the acceptance comes from having all information on system and particular recording delivered by this turntable, and this knowledge allows us to calmly listen to virtually any pressing and release. I have not found even a single record that I would have to remove from the platter before the music ended.

Another important feature of this design is momentum of the presentation. This is a quality known from top-mass-loader, such as the flagship TechDAS top Transrotors; partially also from the SME 30/12 and said Sparta Kronos Audio. It develops sound in a way that makes us believe that we deal with the real size room, in which the recording was registered and the real size of the instruments. This is obviously a trick, otherwise the audio would have no reason for existing – it is not possible in an average listening room, with loudspeaker smaller than two meters, to reproduce something that would be similar to the real event. Helix 1 does not break the rules of physics, nor "smashes the walls and ceiling". But it is so convincing in it that we almost immediately accept that we actually listen to something real.

Because along with differentiation, momentum and power we get excellent dynamics and attack speed. It is the latter that defines how close does the system approach the real sound. Here it is extremely well done, because even though it's obvious that we listen to recordings, all elements of the sound build up a credibility of the performance. There is, for example, a really fast kick drum, an attack of metal cymbals is reproduced brilliantly, sibilants are clearly marked in vocals (because they are natural part of the voice). But it doesn't stop there – the attack phase is followed with a proper weight of each sound that gives it the momentum I was talking about.

I mentioned the upper part of the band - if was to try to determine the tone of sound that we get from the tested system (turntable + arm + cartridge), I would have to say that it is neither bright nor dark; it does not resemble in this regard either TechDAS Air Force Two nor Kronos Sparta. The closest in terms of color balance and saturation in my (a bit risky) opinion is TechDAS Air Force One. In a blind test I would probably say that it presented maybe a bit scaled down version of top TechDAS deck. Which considering such fundamental design differences poses questions about the real impact of techniques and technologies on the sound and how we interpret them while listening.

On one hand Helix 1 is characterized by a sonic signature that comes from soft suspension, which would make it closer to other such designs (though, let me add, rather to SME than Kronos and Avid). It offers a beautifully colorful sound, great vividness and lack of harshness; the latter by the owners of the mass-loaders may even be considered as a sign of warmed up sound. But it is not a warm sounding turntable, far from it. It delivers a lively and dynamic sound, rich in detail, with a strong, well controlled bass, which in turn sends us back to the non-suspended turntables. And finally, it is not something in between - let's say (to stay in the same price range) - TechDAS Air Force Two and Kronos Audio Sparta. "Between" always means some compromise and often, unfortunately, lack the advantages of both solution and instead their combined drawbacks. The Mark Döhmann's design offers the best qualities of both competitors, but is not a golden mean but rather a separate, top quality party.

One that remembers the sound of other top turntables could of course point out their particular advantages. Sparta, for example, has a richer lower midrange and in results renders more tangible phantom images, this is how a turntable, understood as the type of a source, sounds like. In my opinion Avid Reference represents very similar type of sound. Air Force One is even better in shaping the leading edge, that is naturally soft, but extremely fast. On the other hand model Two of the same company, as well as once Kuzma Reference, and recently another Reference by Mr. Sikora, have even more accurately portrayed the attack of the sound, they are even better in detail retrieval. Helix 1 sound more like them in this respect than any other, above mentioned, suspended decks. None of them, except perhaps Air Force One, does not render such a fantastic soundstage depth or such momentum as the herewith reviewed turntable.


This is the first known to me turntable built around MinusK system. It is not placed on top of it, it doesn't use it as a decoupling system but actually is integrated with it. Such a radical exploitation of any technology does not happen to often and I'm incredibly curious about results it could yield used for a CD Player.
Combined with the engineering skills of Audio Union it resulted in an incredibly fast sound with great momentum. Differentiation provided by Helix 1 is amazing and the sound reminded me a bit an analog master-tape, ie. there was no warming up of the sound that is characteristic for vinyl records. It comes at a cost of this slight stiffening of the upper bass attack and not really "sweet" treble. Maybe some music lovers will prefer designs that offer richer midrange. However, if you seek the truth, but one that generates interest in material you're listening to, be sure to give it a try, because it's a great example proving how to show abundance of detail and not kill listener with it, how to tell about how the album was recorded, but not spend all time just talking about it.

The turntable is quite large, but its its actual is much larger than actual area between its feet. The manufacturer recommends that the shelf one intends to place this device on should be at least 620 mm wide and 500 mm deep. It should also have a load capacity of over 70 kg. The basis turntable is made from precision machined aluminum - it has a height of 120 mm. Vibration damping element is made of a polymer, same as the mat. Along with the MinusK system and the platter it adds to the total weight of 50 kg. Front of the base was cut out so that one could see the MinusK system. Weighing 15 kg platter, composed of several layers of different materials, features a lowered center of gravity. The upper parts has a damping layer in its rim - the solution is called EDR - Edge Damping Ring. One can screw a clamp on the threaded the axis of the platter.

The main bearing has been developed specifically for this turntable by Stanislava Stoyanova and is made of so called "maraging steel". Steels of this type are generally characterized by high nickel content, very low carbon content and the use of substitutional elements or precipitates to produce age-hardening. Steel pin rests on ceramic ball. The material used for the lubrication of bearing was sourced from the aviation industry.

The motor has been positioned very close to the main bearings. It is a type of belt drive - two belts of circular cross-section transmit torque to the lower plate. This is a solution with a powerful motor called HTAD - High Torque Adjustable Drive. It is controlled by a digital converter associated with the 16-bit monitoring system allowing to track the platter at 120 000 points per revolution. The controller features many different work modes, that can be accessed via port, which connects to the computer.

The turntable may accommodate one or two 9 "to 12" tonearms. The platforms where the tonearms are installed are not rigidly fixed to the board but decoupled with magnets.

The power supply is fitted into a very solid, well-made aluminum housing. On its front panel there are two switches – with one we can turn off the PSU and deck's logos illumination, and the second turns on the system of pumps that suck the record to the platter. This solution known, eg. from the Air Force One turntable, is optional - the switch in the reviewed unit was inactive. The power supply connects to the turntable with two cables.

Specifications (according to manufacturer)

Dimensions (turntable/PSU):
600 x 480 x 250 mm/483 x 480 x 133mm
Weight: 50 kg
Selectable speeds: 33,33/45 rpm (optional – 78 rpm)
Motor: 100 W



- Turntable: AVID HIFI Acutus SP [Custom Version]
- Cartridges: Miyajima Laboratory KANSUI, review HERE | Miyajima Laboratory SHILABE, review HERE | Miyajima Laboratory ZERO (mono) | Denon DL-103SA, review HERE
- Phono stage: RCM Audio Sensor Prelude IC, review HERE

- Compact Disc Player: Ancient Audio AIR V-edition, review HERE

- Line Preamplifier: Polaris III [Custom Version] + AC Regenerator, regular version review (in Polish) HERE
- Power amplifier: Soulution 710
- Integrated Amplifier: Leben CS300XS Custom Version, review HERE

- Stand mount Loudspeakers: Harbeth M40.1 Domestic, review HERE
- Stands for Harbeths: Acoustic Revive Custom Series Loudspeaker Stands
- Real-Sound Processor: SPEC RSP-101/GL
- Integrated Amplifier/Headphone amplifier: Leben CS300XS Custom Version, review HERE
- Headphones: HIFIMAN HE-6, review HERE | HIFIMAN HE-500, review HERE | HIFIMAN HE-300, review HERE | Sennheiser HD800 | AKG K701, review (in Polish) HERE | Ultrasone PROLine 2500, Beyerdynamic DT-990 Pro, version 600 - reviews (in Polish): HERE, HERE, HERE
- Headphone Stands: Klutz Design CanCans (x 3), review (in Polish) HERE
- Headphone Cables: Entreq Konstantin 2010/Sennheiser HD800/HIFIMAN HE-500, review HERE

- Portable Player: HIFIMAN HM-801
- USB Cables: Acoustic Revive USB-1.0SP (1 m) | Acoustic Revive USB-5.0PL (5 m), review HERE
- LAN Cables: Acoustic Revive LAN-1.0 PA (kable ) | RLI-1 (filtry), review HERE
- Router: Liksys WAG320N
- NAS: Synology DS410j/8 TB
System I
- Interconnects: Acrolink Mexcel 7N-DA6300, review HERE | preamplifier-power amplifier: Acrolink 8N-A2080III Evo, review HERE
- Loudspeaker Cables: Tara Labs Omega Onyx, review (in Polish) HERE
System II
- Interconnects: Acoustic Revive RCA-1.0PA | XLR-1.0PA II
- Loudspeaker Cables: Acoustic Revive SPC-PA

System I
- Power Cables: Acrolink Mexcel 7N-PC9300, all system, review HERE
- Power Distributor: Acoustic Revive RTP-4eu Ultimate, review HERE
- Power Line: power cable Oyaide Tunami Nigo (6m); wall sockets 3 x Furutech FT-SWS (R)
System II
- Power Cables: Harmonix X-DC350M2R Improved-Version, review (in Polish) HERE | Oyaide GPX-R (x 4 ), review HERE
- Power Distributor: Oyaide MTS-4e, review HERE
- Stolik: SolidBase IV Custom, read HERE/all system
- Anti-vibration Platforms: Acoustic Revive RAF-48H, review HERE/digital sources | Pro Audio Bono [Custom Version]/headphone amplifier/integrated amplifier, review HERE | Acoustic Revive RST-38H/loudspeakers under review/stands for loudspeakers under review
- Anti-vibration Feets: Franc Audio Accessories Ceramic Disc/ CD Player/Ayon Polaris II Power Supply /products under review, review HERE | Finite Elemente CeraPuc/ products under review, review HERE | Audio Replas OPT-30HG-SC/PL HR Quartz, review HERE
- Anti-vibration accsories: Audio Replas CNS-7000SZ/power cable, review HERE
- Quartz Isolators: Acoustic Revive RIQ-5010/CP-4

- FM Radio: Tivoli Audio Model One