Designers Fern & Roby of Richmond, Virgina have launched a $6500 turntable composed of a balanced bronze platter atop a cast iron plinth. The unusual audio (and heavy) component combines an industrial look with luxury.
Cast Iron and Bronze Turntable
UPDATE: Since we first published this post, they have named the 100lb. turntable The Tredegar F&R Reference and they offer the Tredegar (price upon request) with their own Unipivot tonearm and the excellent arms made by German designer and craftsman Frank Schröder here
Fern & Roby have the following to say about the turntable:
In terms of audio engineering, our design is defined by a high-mass and balanced platter concept using a 70-pound cast iron plinth to reduce resonance and achieve vibration-dampening throughout the system. It has a cast and turned 35-pound bronze platter, dynamically balanced to 1000 rpm. This is a crucial aspect of the bearing design–our single point bearing and center-of-mass design is a low-contact and low-friction concept that takes advantage of the dynamically balanced platter to get the best performance.
Our turntable couples a traditional synchronous AC motor with modern digital speed control techniques including real-time measurements of the platter speed, with an optical sensor feedback to control the platter speed and make micro adjustments as needed. Most turntables in its class use the 60Hz of the AC mains to turn the motor at a fixed speed and then rely on pulley size ratios to achieve the desired platter speed (33 ⅓ or 45 RPM).
In this topology, there is no way to account for belt slip, pulley wear or the effects of temperature change on the system. In addition, the mass of the platter design is constrained by the “stall torque” of the motor. A platter of desirable (large) mass would require a motor of undesirable size and noise.
By synthesizing the sinusoidal drive waveforms required to turn the motor, the Fern & Roby system is not limited to a fixed motor speed or fixed drive power. This allows for a design with extravagant platter mass coupled to a modestly sized motor. From a standstill, the platter is accelerated gradually to the desired speed in order to stay below the motor’s stall torque. The platter’s speed is determined 48 times per revolution with a precision-cut optical interrupter wheel mounted on its underside.
Once at the target speed, the motor’s drive power is reduced to the bare minimum that is required to overcome bearing friction and stylus drag. Reduced motor drive power reduces noise and vibration. Tiny adjustments are made infrequently to the drive speed as needed to maintain exact platter speed. These dynamic drive speed adjustments are limited to 0.003% and only happen one time per revolution of the platter. This delicate approach to speed control minimizes “wow” distortion.
A green LED indicator beside the mode selector switch is used to indicate “in-bounds” platter speed. Any time the platter speed is more than 0.23% above or below the target speed, the LED indicator switches from green to orange while the motor control compensates to correct the speed into the desired rpm.
The turntable is offered standard with a Rega 303 tone arm, but we can supply a variety of tone arms with a custom heart pine arm-board upon request.
The base is supported on levelling feet accessible from above and as an accessory we have a 1-1/4″ thick cork isolation mat with Sorbothane pads to protect your furniture and further isolate the turntable from noisy environments.
Materials:Cast iron, bronze, heart pine, electronic & audio components.
Dimensions: 18.5″ L x 13.5″ W x 3.5″ H
Price: $6500 (subject to change)
The also have a matching amp:
Please inquire to audition at a listening room in Richmond, Virginia.
Fern & Roby will be exhibiting and auditioning our entire audio line at the Capital AudioFest in Rockville, Maryland, August 28th-30th, 2015.
learn more here
Fern & Roby of Richmond, Virginia are fascinated with materials, processes and design. Their products range from small machined hardware and accessories to monumental tables and audio components. See more here.