Thorens New Reference Turntable – Preview

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Thorens was originally launched in 1883 by Herman Thorens. Now, 140 years later, the company has launched their latest Reference turntable. This Flagship model is unique in featuring a fully active vibration isolation system that was developed in collaboration with German active vibration isolators manufacturer Seismion. The active system is based around high-sensitivity piezoelectric acceleration sensors, an all-linear electronic control circuit and is based on Seismion’s Reactio active vibration isolator technology.

Turntables are all about vibrations and the only ones you want your cartridge to detect are those coming from the vinyl grooves modulation. So with modulation amplitudes that are less than the wavelength of light, isolating the turntable from external vibrations is of paramount importance. With this in mind Thorens set about creating a vibration isolation and control design that had never been achieved in turntables before.

Thorens Reference turntable vibration control uses traditional mechanically isolated elastic mounts plus active control that is set up as a classic feedback topology. Seismion’s explanation is as follows:

“Especially developed acceleration sensors with piezoelectric ceramics monitor the amplitudes of the isolated platform with high precision. These measured signals are converted into the required actuation forces by an analog control system, which drive contact-less voice coil actuators. Multiple of these active control loops are in action in order to isolate all six degrees of freedom.

The basic idea of ​​active control is to reproduce a so-called “sky-hook damper“. Unlike in the passive system, this damper is not coupled to the (vibrating) floor, but to a virtual, stationary attachment point. Therefore, no further disturbances from the ground are introduced into the system via this virtual damper, and the sky-hook damper only has advantages for isolation and stabilization purpose.”

This sophisticated electro-mechanical Sky-Hook-Damping system isolates disturbances below 1 Hz. Moreover, it is claimed to reduce vibrations to less than 1% (-40 dB) at frequencies of 10 Hz and above, being capable of dealing with vibrations as small as a nanometer and down to a picometer using its contactless actuators .

Together with the chassis layers of high-damped materials, to further reduce resonances, Thorens has made the system’s centre of gravity close to the plane of isolation in order to reduce the coupling of horizontal vibrations and tilting motions. This isolation system also stabilizes the whole sub-chassis on which the platter is placed. Completing the isolation design is an adaptive levelling system that maintains the horizontal position to within 20 micrometers.

Thorens choose a belt drive system that they say has been selected to isolate the platter from motor vibrations and its design has overcome the rotation speed errors inherent with belt-drive designs thanks to the dual “ultra-high-precision quartz oscillators”, that are said to maintain the platters rotational speed within a range of 33.3332 to 33.3334 rotations per minute over 20 years. The new motor design featuring a high-quality German-made 3-phase synchronous motor, which is driven by three all linear power amplifiers with 120° shifted sine signals.

Finally the Reference turntable can support three tonearms of 9″, 10″ or 12″ in length. It is said to come with the newly developed 12″ TP160 cutting bearing tonearm with continuous silver cabling and the Thiele TA01, which is said to combine the precise and rigid guidance of a pivoted tonearm with the advantages of a tangential tonearm.

For the news release visit the Thorens web site.

Read the Thorens Reference brochure here.

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