Turntables are back with a vengeance, but time doesn’t stand still. Technology’s pace allows us to revisit problems and solutions of the past with new eyes and new means. Sempersonus looked at one of the older and most cherished drive systems – idler drives – and proceeded to iron out its kinks and foibles with modern technology and materials. The result surprised them and will surprise you. Starting with the drive system, motion is supplied by a 10-pole BLDC motor, epicyclically driving the aluminum platter through a low-elasticity rubber drive wheel. The motor is attached to a telescopic cradle using sorbothane rings for vibration decoupling.
Construction
The platter of the Sempersonus TE1, of medium weight (3.3Kg), is constructed from aluminium and acrylic with the major mass around its circumference for a greater Moment of Inertia. Its underside is covered in butyl rubber to quell any ‘ringing’. It rotates on an inverted bearing design, its weight supported by opposing neodymium magnets. To top it off, we use a two layer rubber / cork mat, for further isolation. Everything ties together at an aluminium / acrylic composite chassis X-frame, for rigidity and vibration damping. The frame itself, bolts onto a plinth made from steel reinforced concrete, where all other parts – armboard, sideboards, power and control electronics – are also bolted to, on precision located mounting points. The inboard power supply, line filters the mains supply before converting it to 12V DC and stabilizing it. It then feeds the motor controller, which features electronic speed switching (33/45), along with quick spin-up and quick stop characteristics. The correct speed is constantly monitored and accurately maintained thanks to feedback from a 1000-step optical encoder. At the same time, the right amount of torque provided – i.e. the absolute minimum required at all times – is continually adjusted based on feedback from the current levels required by the motor.
Hidden complexity
Complexity is hidden, or rather function doesn’t dictates form. Sempersonus strived for a classical, contained appearance, able to subtly fit into any decor and not scream about itself. Beautiful wood panels side frame the turntable, while all other surfaces are covered in Alcantara for a truly ‘no-fingerprints left’ finish and, if being honest, for a difference! The standard combination includes a Jelco SA-750EB arm and a Denon DL-110 cartridge. However, armboards for other arms can be supplied instead, with no additional charge. For protection from dust – and little fingers – an optional dust cover is available. It features a novel tilt/slide damped hinge that allows for a more compact vertical footprint. Also included is a useful holder for LP covers, enabling their display while the record is spinning.
Visit the Sempersonus website.
