DOHMANN Helix 1 Turntable w/ Minus-K isolation platform incl Schroder CB tonearm

DN 03 TT HELIX1
NZ$ 74,995.00 ea (incl. GST)
Dohmann

unparalleled analog playback performance

New
“Dohmann Helix 1 design is a significant enhancement on state of the art and its motion control defines what will become part of a new breed of “super turntables”.

A new exciting project is on the run. Helix 1: for many the most admired turntable at the Munich High End Show is now launched.

At Thrax our goal is to achieve exceptional performance by using cutting edge technology and innovative design strategies. All of our components are explicitly conceived and manufactured to meet or exceed this goal. To preserve our heritage and ensure this performance is conveyed throughout the signal chain, we decided to invest into the development of a complete Thrax reproduction chain and to further widen the existing product portfolio. 

When facing challenges beyond our expertise we repeatedly applied old wisdom – which is to ask those who know. In the process questions flowed back and forth and this led to an exchange of ideas, spawning true collaboration. 

This exchange prompted the concept of an audio union – a joining of like minds. The synectic process which led to the creation of Audio Union brings forth products that are fruits of real collaboration with leaders in their respective fields. This is no OEM – rebadging and marketing ploy. Here we use knowledge from the best minds and technologies they developed as a stepping-stone to new ground-breaking designs. Applying out-of-the-box thinking and wisdom gained in multiple fields aids in producing a proprietary Thrax solution setting new levels of performance. 

The second group of products to be launched under the Audio Union initiative relates to the analog replay chain. 

As usual we started with a bit of history and a lot of research. Operating principles of cartridges, tonearm and turntables were studied in detail. Emblematic designs and technological achievements were taken as references. Inspiration was drawn from Micro Seiki, EMT, numerous Japanese direct drive statement designs and the usual current trend setters. 

Having a Caliburn by Continuum Audio Laboratories at hand showed where each of the other designs have been compromised. So the question was how to do better and where to go from here. 

Trying to get hold of Mark Döhmann of Continuum Audio Labs proved a difficult task as he had left the turntable design world in early 2010 to pursue some software development projects in bionic engineering. 

Theoretical concepts and ideas kept accumulating until critical mass was reached in 2013r and the technology needed to realise it became available. 

A statement turntable project was born and it required that all aspects of the design to be at the current state of the art. This involved know how in a lot of different fields of science and no single person has all that knowledge. A “moon shot” sort of problem. The more you know, the more you realise what you don’t know. So we challenged the best minds to come up with new and better ways to make the journey to “nirvana” possible: 

Welcome the Döhmann Helix 1 turntable with the Schröder CB/CF tonearm. These form part of an Audio Union project by Thrax.

The Dohmann Helix 1 turntable is the result of complex, and advanced engineering technologies, needless to say this is truly next-level thinking in design. 

The Dohmann Helix 1 features advanced motion control and many proprietary technologies such as incorporating a Negative Stiffness Mechanism (NSM), Vibration Isolation with Mechanical Crossover Technology, and a Tri-Modal Platter system (to name just a few) that sees the 15 Kg platter fitted with an Edge Damping Ring.

The Döhmann Helix 1 delivers unparalleled analog playback performance due to its unique Micro Signal Architecture© (MSA) engineering that sets new noise reduction and micro-signal preservation benchmarks.

MSA is a cohesive design approach that uses the most advanced available techniques to remove physical and mechanical vibration and electrical noise.

While the MSA concept sounds obvious and simple, implementing this revolutionary design required years of research and development. MSA is integral to the Helix 1’s many engineering innovations.

The Helix 1 features a radical approach to advanced motion control to deliver complete control of the motor and platter. This has opened new levels of music detail retrieval. Another innovation is in the complete integration of a customised negative stiffness isolation system, which results in an ultra-low natural resonance. This effectively isolates the turntable from the surrounding environment.

The 120mm (four-inch) plinth is made from precision CNC aircraft grade aluminium and structural alloys and weighs close to 50 kg (100Lbs) when assembled. Connected by a series of interlocking plates which are fitted closely to the MinusK suspension system and allow for the mounting of the sub-systems such as motor, bearing, tonearm combinations. A laminated glass plate is used to add ballast and lower the centre-of-mass. This glass plate provides visual access to the MinusK suspension for performance monitoring. 

The 15Kg (30Lb) platter is made of triple layer of an engineered thermoplastic (made for Audio Union by a European supplier of polymers), and non-ferrous alloy machined to close tolerances. Each high-mass platter is balanced and shaped for lead-in groove and record label.Special features include an EDR – Edge Damping Ring which damps the platter and LP edge and a damping mat to interface to the LP.”

Audio Union’s selectively chosen network of dealers and distributors are convinced the Döhmann Helix 1’s vinyl playback performance is without equal. 

Audio Union is an organisation of respected engineers, research scientists and international manufacturers dedicated to restoring the true meaning of “High Fidelity”. 

Audio Union products are manufactured in the USA and the European Union.

HELIX 1 ARCHITECTURE
Helix 1 rewards the listener with the closest facsimile to master tape yet realised. How do we know this? 

Our engineering facilities and listening rooms use several studio reference level and highly modified master tape systems to compare the Helix 1 along with a range of other well-known turntables. 

The specifications of the Helix 1 demand the ultimate in noise suppression and isolation systems to allow the turntable and pickup arms to deliver the micro-signals buried in the vinyl grooves on well authored LP’s.

Every aspect of the turntable design requires the preservation of the micro signals found in the groove of the LP to be retrieved with as little modification and distortion as physically and electronically possible.

Döhmann Helix 1 by Audio Union table incorporates several engineering advances to deliver the lowest resonance profile for any pickup arm and LP combination.

MICRO SIGNAL ARCHITECTURE (MSA)©
Micro Signal Architecture© (MSA) is a cohesive design approach that uses the most advanced available techniques to remove physical and mechanical vibration and electrical noise.

Entering the world of microscopic endeavours there are barriers; for example the actual method of measurement can deflect the measurement itself. Thought is needed for the measurement system to deliver the best result. For example numerous research facilities around the globe have millions of dollars invested in microscope systems examining atomic scale objects to enhance our understanding of the physical world. 

Images at the nanoscale are extremely sensitive to external vibration even under vacuum. Experiments utilizing sensitive equipment such as; Atomic Force Microscopes, Electron Microsopes and laser scanning systems, require the staff to stand still in the building and machinery to be disabled, when a sensitive image is captured by the microscope. Similar to hollywood movies of submarine warfare!

In actuality, even foot steps several floors above can transmit through concrete structures and blur the images. This is not an elegant solution for such expensive research, only with the installation of advanced vibration suppression and isolation can the images be retrieved in fine enough detail to show new insights. So how analogous is this to audio? 

For analog systems such as the audiophile turntable it is extremely relevant to the performance of the table. For vinyl playback, the enemy of any signal found in the mechanical groove by stylus tracing is also vibration and electrical interference

Many audiophiles and music lovers lament the lack of isolation on turntables, from entry level to cost-no-object designs. Existing turntable suspension and isolation systems may not achieve the real world performance objectives they claim and listeners experience feedback, information blurring and over-weighted boomy bass response. Modern homes, are not designed for vibration control. In older homes with wooden floors these systems become unstable and do not stop footfall or feedback loops occurring (the classic tiptoe around the suspended turntable else your cartridge mistracks syndrome). This is predominantly due to the natural frequency of these suspension systems not being low enough (0.3hz-1.5hz). 

The innovation in Helix 1 lies in the ingenious way the NSM isolation technology is integrated. The turntable and NSM device form a fully acoustic and mechanically balanced system. The result is a precisely designed “mechanical crossover” that harmonises the forces at play between the incoming external acoustic and mechanical vibrations (the environment) and the self-generated internal vibrations caused by bearings, motor and chassis dynamics (the hardware).

By complex use of recent developments in software measurement technology for Chladni plate analysis and engineering “cymatics”, the team at Audio Union has developed a complex chassis system that effectively damps vibration utilizing a semi-active topology.

The Helix 1 showcases the use of semi-active vibration suppression in a prestress accumulation/release (PAR) design. This is a method to convert the strain energy of a vibrating system into kinetic energy, which is then released from the system by means of a dissipative device. This delivers superior isolation to the level demanded by the most sensitive electron microscopes and atomic force microscopes.

The design is semi-active; it does not require adding any substantial amount of energy, is highly efficient and cost effective compared to an active system. Active systems have a tendency to add noise to the operating environment, this is also undesirable. Our approach eliminates this unwanted noise that can disrupt the stylus to record interface.

MECHANICAL CROSSOVERS
One of the major influences in the sound reproduction of vinyl play back is mechanical vibration. After all, turntables are mechanical devices. So what if a “mechanical crossover” concept could be extended to create a smooth continuous pathway to channel vibrations away from critical areas on a turntable?

Historically mechanical crossovers have been well documented in loudspeaker design for decades. Experienced designers such as Dr Plamen Ivanov Valtchev in Europe have published numerous papers (AES, patents, etc.) on advanced mechanical speaker structures and designs. 

Here is a summary of one successful implementation.

Coupling the cone of the speaker to a voice coil bobbin through a compliant section and directly attaching a small lightweight whizzer cone allows the compliant section to serve as a filter!

The main cone is not vibrated at higher frequencies as whizzer cone responds to all frequencies, however due to its smaller size; it limits the output at higher frequencies, thereby implementing a “mechanical crossover function”.

From this method we learn the shape and weight of the components influence acoustic behaviour under vibration. Therefore, selection of materials and the suspension elements used determines the crossover frequency and effectiveness!

By extending the mechanical crossover concept to the Helix 1, physical zones can be defined on the infrastructure that focused vibrations away from key areas (platter, bearing, motor, tonearms, floor modes), establishing a smooth continuous pathway to channel vibrations away from critical areas on the turntable! 

The Helix 1 has been designed to reject low frequency vibrations coming up from the floor by using the MinusK NSM isolation system and drive higher order vibrations generated through motor noise away from the bearing and platter via a complex coupling to the chassis. For these higher order vibrations local isolation, absorbing, redirecting and suppression technologies are employed including semi-active decoupling from motor vibration.

The Helix 1 is designed to operate flawlessly in non-ideal environments suffering from floor borne vibrations such as older houses with wooden floors, upper floors, attics and any external vibrations which are carried through buildings - even those made from concrete steel, and brick.

MEASUREMENT AND VISUALISATION TECHNIQUES
By creating a visualisation technique to see these vibrations in real life, the team can see where the vibrations “collected” on a chassis under real life operating conditions. 

Chladni Plate Analysis

Extensive use of Chladni plate analysis and the subsequent use of pre-stress in the chassis design allowed the positioning of "anti” vibration zones in critical areas (Motor, bearing and arms) vs trying to damp it with one solo material or less effective broad-brush approaches. 

Our experimentation confirmed no “magic bullet” exist for resolving the challenges facing existing turntable designs. It is the precise blending of high-tech materials and topologies which has created the sonic breakthroughs in the Helix 1. Vibration analysis has advanced since the pioneering work of Robert Hooke in 1680 and Ernst Chladni in late 1700's. Chladni’s Law F=C(m+2n)p can be used in complex eigenmode and wave analysis of turntable chassis. The Chladni method is used by artisans and scientists alike in the creation of musical instruments and engineering solutions.

In simpler terms, "the bearing is the centre of the “universe” where “planets” (Motors and Arms) sit on an orbital plane (the chassis/plinth). Vibrate the plane (chassis/plinth) by internal or external means and you get vibration patterns and nodes which become visible to the naked eye using Chladni plate analysis.

By placing the bearing and motor and arms into “optimal zones” where vibration was well damped or controlled we provided the best possible place on the chassis for the susb-system to sit with the lowest possible vibration. Helix 1 chassis research created several eureka moments!

MOTION CONTROL
Helix 1 design is a significant enhancement on state of the art and its motion control defines what will become part of a new breed of “super turntables”. 

HTAD – High Torque Adjustable Drive. This is where torque curves and “ballistics” can be adjusted by “musicians and artisans” to “voice” the table for ultimate performance and musicality. This software driven perspective unveils a unique capability for system designers to work with every aspect of a drives performance and open new vistas into music performance. 

The precision motor industry is changing rapidly to embracing a software driven architecture. Helix 1 technology is taken from latest developments in sub micron servo drive systems for precision optics and adapted by our engineering team to deliver superior motion control to the Helix 1.

The Helix 1 motor control system is a digital closed loop servo with greater than 16bit resolution. Absolute positioning reading occurs over 120,000 discrete positions of the rotor per revolution. The motor spins several hundred times to achieve one revolution of the platter thus increasing the system resolution by an order of magnitude over a direct drive topology.

In laymans terms; this means at 33/45 rpm platter speeds we have an incredibly high number of checks on the speed stability per second. This information is fed to a super fast microprocessor in the servo control and our custom written software then defines the stiffness and the ballistics of the system and responsiveness of the servo loop. Different ballistics (inertia/force ratios) can be programmed to yield different sonic signatures and sound dynamics. Using a laptop interface we can tune sonics of the drive and control a comprehensive set of variables.

The table can act like a high torque Direct drive or like an underpowered low torque design depending on servo programming. Torque force can be adjusted to suit sonic palettes and the frequency of the drive shifted to areas that are better handled by the mechanical design and vibration control. 

ogging is prevented by a proprietary coil design that smooths the motor to vanishing low levels of vibration. Our motor design team has delivered extremely low motor noise on the Helix 1. We have not found any comparable system able to attain similar results. 

he speed is factory set for 33 and 45 and does not need adjustment in normal operation. However if a user wishes to adjust the reference speed a software application via a smartphone/tablet/computer allows adjustment. It is also able to be securely connected to our service technicians for diagnostics and firmware / software upgrades. Advanced settings are provided to factory trained technicians via stored named reference files for clients custom installations.

PLINTH
The 120mm (four-inch) plinth is made from precision CNC aircraft grade aluminium and structural alloys and weighs close to 50 kg (100Lbs) when assembled. Connected by a series of interlocking plates which are fitted closely to the MinusK suspension system and allow for the mounting of the sub-systems such as motor, bearing, tonearm combinations. A laminated glass plate is used to add ballast and lower the centre-of-mass. This glass plate provides visual access to the MinusK suspension for performance monitoring.

PLATTER
The 15Kg (30Lb) platter is made of triple layer of an engineered thermoplastic (made for Audio Union by a European supplier of polymers), and non-ferrous alloy machined to close tolerances. Each high-mass platter is balanced and shaped for lead-in groove and record label. Special features include an EDR – Edge Damping Ring which damps the platter and LP edge and a damping mat to interface to the LP.

SPINDLE/SPINDLE HOUSING
High reliability and ultra low-noise operation were specified as part of the architecture. Audio Union engineer Stanislav Stoyanov developed a new low height, high stability custom bearing design for the Helix 1 using MARAGING STEEL to provide the desired capabilities, precision and low thermal and flex modulus. A single, ceramic ball, located at the bottom of the spindle is used for trouble-free operation on a quiet thrust-pad. The high tech lubrication system is sourced from the aeronautical engineering field to ensure low noise operation.

RECORD CLAMP
The record clamp is designed for ease of operation and secures the LP effectively on the platter surface and flattens even severe warps in poor quality LP’s. The clamp is a multi-piece design which has a reduced damage profile in the event a user accidentally drops the clamp onto an LP during operation. This was designed for “real-world” use (late night LP sessions and low lighting where operator fatigue sometimes occurs).

MOTOR
A precision single spindle high-torque motor featuring zero cogging is used. The motor can supply up to 100 watts of power for the most demanding control needs. By careful software controlled ballistics the belt system is gently started and bought to rest to avoid premature wear. Speeds are factory set and rock solid.

BELT
Dual high damping o-ring belts are provided for stable drive transmission.

ARM BOARD ASSEMBLIES
The Helix 1 supplies two armboards (for dual arms) that are removable and can be predrilled for most commercially available arms or left blank for future use. The armboards are able to be fitted or removed externally with arms mounted. No need to dismantle and recalibrate. The chassis has a damped tubular cross-section underneath which precisely locates the armboards relative to the bearing and platter. This provides a very rigid system with minimal flex and movement.

TONEARMS
The Helix 1 is able to function with your choice of arm. We recommend the Schröder CB Arm which has been custom designed to work seamlessly with the Helix 1 and delivers exceptional performance.

SET UP
The Helix 1 turntable can be mounted on normal non-audio grade furniture (as the suspension system will work independently) and fit in with any architecture and decor. Any platform the turntable sits needs to support 70Kg (140 pounds) and is at least 620mm wide and 500 mm deep.

Helix 1 includes an owner’s manual that includes step-by-step directions for set up although we recommend working with your authorised dealer. The table is very easy to set up, use and play.

SYSTEM COMPONENTS
The Helix 1 system comprises a turntable with its internal suspension system using a unique Negative Stiffness Mechanism (NSM) isolation technology and integrated motor using twin belt drive for speed accuracy.

TURNTABLE CONTROLS
All controls for normal 33 or 45 operation are located on the turntable top panel. 

CONTROL BOX
A separate “control box” motion control servo drive is located in separate 3RU standard rack size housing which can be placed conveniently nearby or out of sight. 

The unit comes pre-calibrated to precise speed for 33 and 45 from factory. The drive system monitors the speed constantly over 130,000 times per revolution to deliver direct drive like accuracy without speed drift. Speed adjustment is accessed via simple USB interface on the Control box and can be done remotely or onsite using a simple GUI connected to the USB direct or via secure Wifi. 

Versions availbale in anaodised silver/black halftoe and / orin all black and all silver anodized configurations. 

UPGRADE PATH
Some customers have requested Vacuum hold down. This feature will be offered as an upgrade for those users who seek this capability. 

The current bearing design allows for vacuum hold down and the Control Box has been specified to allow for fitment of a vacuum module. This will be field tech upgradeable when released.

Features

Specifications

Reviews

Awards

Videos

Features

FEATURES INCLUDE
MSA - Micro Signal Architecture©
NSM - Negative Stiffness Mechanism Vibration Isolation -  0.5 Hz (Fz) Vertical / 1.5 Hz (Fz) Horizontal
MCT - Mechanical Crossover Technology
TMP - Tri-Modal Platter system
EDR - Edge Damping Ring
TDS - Tone arm Damping System
RTS - Resonance Tuned Suspension
DLC - Diamond Like Coating Amorphous Material Bearing Friction Modifier
HTAD - High Torque Adjustable Drive
Speed Selections 33, 45 RPM (78 RPM by request)
Velocity Adjustment Lock – Speed is constantly calibrated over 130,000 times per second to deliver precise 33.33 or 45.15 rpm (factory default).

You will have to judge for yourself, how close we have come to the gold standard. Audio Union dealers and owners are convinced there is no peer in analog LP playback.

Specifications

The Helix 1 turntable is capable of mounting two pickup arms simultaneously and is fully integrated with an internal motor which drives the platter via dual belts.

The turntable comes with separate power supply and servo control box which is connected by two custom cables to the turntable chassis.

The turntable is designed to be mounted on a wide variety of surfaces as it has an intrinsic suspension system fully integrated with the chassis. 

The specification includes the ability for the turntable to work in older style buildings and domestic locations where wooden floors and building movement create instability and issues such as feedback and footfall interference. The Helix 1 is isolated from these issues. 

HELIX 1 TABLE - Width 600mm (24”) x Depth 480mm (19”) x Height 250mm (10”)

HELIX 1 CONTROL BOX - Width 483mm (19”) x Depth 480mm (19”) x Height 133mm (5”) 
Standard 3RU (19 inches) Configuration.

POWER - 120 VAC, 50/60Hz 2 amps or 220/240 VAC, 50/60 Hz 1 amp

WEIGHT - Combined shipping weight is 80Kg (shipped in 2 custom fabricated boxes).
Recommended installation requires a surface capable of supporting up to 80Kg (160 pounds) and a 620mm (25”) wide x 500mm (20”) deep surface for the isolation platform to be able to move freely.

Factory set speed selection by push button for 33 1/3 or 45 rpm.

The Helix 1 allows 33, 45 and if required 78RPM and a wide variety of engineering adjustments to create “audio bliss” that is very user friendly and easy to operate. 

Multiple arms up to 12 inch are accommodated with ease of operation and setup assured. Removable arm boards allow simple interchange and calibration.

Note: Set-up assistance and complete service available worldwide through authorised dealer and representative network.

Reviews

I have seen a standout in turntable design and it is the Döhmann Helix 1. @ RMAF 2015
Rafe Arnott

REVIEW SUMMARY: The sound the Helix 1 was producing was incredibly compelling, engaging and supremely musical. The level of detail and nuance to the sound, the deep, authoritative bass and immense sound-stage scaling made available through the SAT arm and Lyra pick up were deeply involving. I’d be hard pressed to list another turntable that was as capable as the Helix 1 in producing such an absolutely black, dead-silent background for the music to leap from

It’s no surprise to anyone who’s read my frantic scratchings here the past few months that I am an analogoholic. I will never enter a 12-step program for this unabashed addiction from which I craft numerous fetishes. Rare Japanese MC cartridges? Check. Obscure step-up transformers? Check. British valve amps and phono stages? Check. Turntables designed by Mark Döhmann? CHECK.

Döhmann is quite well-known in international audio design and engineering circles for his advanced analog work since the ’80s with turntables and tonearms.

This turntable is the result of complex, and advanced engineering technologies, the likes of which I’m not getting into too much here, needless to say this is truly next-level thinking in design (to me). The people at Audio Union have a great breakdown on the tech. The Helix 1 features advanced motion control and many proprietary technologies such as incorporating a Negative Stiffness Mechanism (NSM), Vibration Isolation with Mechanical Crossover Technology, and a Tri-Modal Platter system (to name just a few) that sees the 15 Kg platter fitted with an Edge Damping Ring.

From the Audio Union website:
“Helix 1 design is a significant enhancement on state of the art and its motion control defines what will become part of a new breed of “super turntables”.The 120mm (four-inch) plinth is made from precision CNC aircraft grade aluminum and structural alloys and weighs close to 50 kg (100Lbs) when assembled. Connected by a series of interlocking plates which are fitted closely to the MinusK suspension system and allow for the mounting of the sub-systems such as motor, bearing, tonearm combinations. A laminated glass plate is used to add ballast and lower the center-of-mass. This glass plate provides visual access to the MinusK suspension for performance monitoring.

The 15Kg (30Lb) platter is made of triple layer of an engineered thermoplastic (made for Audio Union by a European supplier of polymers), and non-ferrous alloy machined to close tolerances. Each high-mass platter is balanced and shaped for lead-in groove and record label.Special features include an EDR – Edge Damping Ring which damps the platter and LP edge and a damping mat to interface to the LP.”

I managed to get a hold of Döhmann down in Australia via email and a very enlightening phone call with Dave Kleinbeck, who is president of Audio Union International.

Here are the questions I asked, and Döhmann‘s responses:

PTA:
Your long involvement in turntable design and research on many types of turntable drives, isolation, vibration control and damping has led you to Audio Union and the design and current production of the Helix 1. This is a radical design on many levels. How does it feel to have accomplished packing so much technology into one design and have the outcome be such tremendous musicality?

Döhmann:
“I’m very proud to be part of a great team of very talented engineers, scientists and designers at Audio-Union. I admire the work of great watch designers who in the last 20 years have had to adapt to the almost ubiquitous use of digital technology and create timeless mechanical designs with ever more complex movements and features. Some of my favourite designs have a visual feature where you can see all the complex mechanical workings. The Helix One  showcases the mechanics, so one can see the inner workings of the suspension system with all its intricate parts. These inner workings are key to the musicality of the table isolating the core systems from deleterious noise and vibration. It looks simple but to get all the mechanisms to fit without adding more and more outrigger devices is a challenge. We managed to do so using advanced software modelling tools. Having a clear vision of the architecture before starting did help too.”

PTA:
What previous turntable designs and industrial or medical designs did you draw inspiration from in the design of the Helix 1?

Döhmann:
“Emile Berliner, Thomas Edison, Garrard, Neumann, EMT, the great Japanese vintage tables, Rockport, and Meitner definitely provided the inspiration. Industrial designs include classic automotive icons and Frank Lloyd Wright, Denton Corker Marshall architectural influences and the pioneering work of George Lucas’ Industrial Light and Magic. Medical inspiration was provided by the great technicians at Scottish firm Glenmorangie.  ;)”

PTA:
How has the design and technology incorporated into the Helix 1 influenced your thoughts on future ideas for turntable design?

Döhmann:
“Software driven systems where every parameter is adjustable and tunable. This is the future.

PTA:
Lastly, how critical, in your opinion, is the interface between tonearm and turntable, vs turntable and its environment.

Döhmann:
“The foundation of a good house is often unseen as we focus on the parts we see. But build it on an unstable foundation and you will soon experience the lack of foresight and planning in a crumbling house. The foundation of a turntable is its isolation from the environment it sits on. The Tonearm benefits from this. Look back far enough and you will see speaker floor interactions showing up in Tonearm responses. Remove that interference and you advance the performance. Early EMT tables understood this. Helix One takes that to the level demanded by atomic force microscope users for critical operations. That’s where the world of science has opened the door to better music.”

The sound the Helix 1 was producing was incredibly compelling, engaging and supremely musical. The level of detail and nuance to the sound, the deep, authoritative bass and immense sound-stage scaling made available through the SAT arm and Lyra pick up were deeply involving. I’d be hard pressed to list another turntable that was as capable as the Helix 1 in producing such an absolutely black, dead-silent background for the music to leap from.
........ Rafe Arnott

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,... if you seek the truth give it a try
Wojecieh Pacuta

SUMMARY: 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.

EXTENDED REVIEW: A 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.

AUDIO UNION

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 realisation 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.

HELIX 1 TURNTABLE

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 aluminium 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 aluminium latter, to which via sort of separating layer, a lower, wider platter is fixed. It features three layers - aluminium, 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 aluminium 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 aluminium 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 actualisation. 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.

SETUP

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 fibre.

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.

SOUND

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 realise 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 favourites. 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 exercise, or useless theorising, 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 colour 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 characterised 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 colourful 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.

SUMMARY

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.

DESIGN

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 aluminium - 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 centre 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 characterised 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 aluminium 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.

Awards

STEREOPHILE Recommended Components: 2017 Edition TURNTABLES - Audio Union Dohmann Helix 1: US$40,000

Designed by Mark Döhmann, who headed the design team at Continuum Audio and now works under the auspices of Bulgaria-based Audio Union, the belt-drive Döhmann Helix 1 was intended to achieve the same goals as the well-regarded Continuum Caliburn turntable, but at a far lower cost.

Incorporating a CNC-machined aluminum-alloy plinth that itself weighs 100 lbs, the Helix 1 also makes use of a Negative Stiffness isolation platform, a high-torque motor with a software-based control system, a 30-lb metal-and-thermoplastic platter with a permanently installed damping mat, and a screw-on record clamp (a retrofittable vacuum hold-down system is in the works). Paired with the Helix 1 is the Captive Bearing (CB) tonearm from Frank Schröder, also a member of the Audio Union design team.

The CB features a carbon-fiber armtube and ultralow-friction hybrid ceramic bearings that include internal magnetic damping of horizontal motion. MF praised the Schröder CB as a "strong performer for $4000, or even more," and also evaluated the Helix 1 turntable with his reference SAT tonearm—an experience that led him to declare that "the Helix lets the music erupt (as I wrote about the Caliburn 11 years ago)."

Mikey concluded:
"Had I installed the Helix 1 in the same 2005 system that provided the context for the Continuum, I'd have written about it what I felt about the Caliburn: 'no turntable in my experience comes close to its sonic performance and you are guaranteed to hear your favorite demo LPs, indeed all of your LPs, as you've never before heard them.'" (Vol.40 No.3)

Videos

Doehmann Helix 1 with Minus K isolation inside

Bulgaria Based THRAX Builds The Döhmann Helix 1 Turntable