Fully integrated active vibration isolation by Seismion
The Thorens New Reference is the result of Thorens’ strive for the perfect rendition of music recordings. The electrical signals in a turntable are created by mechanical vibrations of the stylus of the cartridge while it moves along the grooves of a vinyl record, which are then converted into the sound.
In exactly the same way, however, all other mechanical vibrations of the turntable also find their way to the stylus. By propagating into the signal path, they lead to distortion and other unwanted effects. The sources of these vibrations are for example building vibrations or people walking around. But the sound waves of the music and self-generated vibrations from the turntable itself also play a role. Since it is not possible to distinguish between music vibrations and parasitic disturbances, these must be avoided. The Thorens design team around Helmut Thiele, who is responsible for the construction and design of the Thorens New Reference, have taken on this challenge.
The Thorens New Reference is the first ever turntable to be designed and optimized from scratch around a fully active vibration isolation system. Thorens teamed up with Seismion, a German company internationally renowned for its class-leading active vibration isolators, to create a turntable that features the vibration isolation system as an integral part of the system design. Seismion fully exploited its expertise in active isolation systems used for semiconductor industry, nanotechnology and scientific laboratories, to create a vibration isolation never seen and experienced in turntables before.
The active vibration isolation is based on piezoelectric acceleration sensors with an extremely high sensitivity, as well as an all-linear electronic control circuit to generate unrivalled low noise- and distortion-free control forces. This sophisticated mechatronic system is based on so called Sky-Hook-Damping and isolates disturbances already below 1 Hz and reduces them to less than 1% (-40 dB) at frequencies of 10 Hz and above. Such a performance is far superior to any other isolation (figure 1). This figure shows the active isolation system – Sky-Hook-Damper – in comparison with a high-performance Air Spring. Especially at the critical frequencies around the resonance, the active isolation has a performance which is up to 100 times better. At 10 Hz it is still about 17 times stronger isolated than with an Air Spring. Other dampers like rubber mounts are on a much lower performance level and therefore not shown in this comparison.