Through the end of Nov 2017 - get a FREE Centroid tonearm with a new SG 1.2
Spiral Groove SG 1.2
The SG1.2 body is comprised of four aluminum layers in two
independent constrained-layer platforms. These two mirror-imaged
assemblies, separated by four carefully positioned elastomers, function
as a single platform. The feet, with Strange Attractor technology and
low frequency damping, are attached only to the bottom layer. The second
layer, which is separated by rigid damping material, provides a stable
platform for the motor. The upper half of the SG 1.2 body isolates the
platter and tonearm in a similar fashion. The bearing/platter assembly
attach to the 3rd plate from the bottom. The top plate, which is
separated by a rigid damping layer, provides the tonearm mount. This
allows motor, platter, arm, and the furniture the turntable rests on, to
remain isolated from each others' vibrations while maintaining critical
alignment between them.
The unique Spiral Groove bearing is made from the same case hardened
steel used for an F1 racing car's crankshaft. Utilizing material made
for high heat, high speed, high wear applications might seem unnecessary
for a turntable bearing, but, it's actually ideal for several reasons.
For one, it allows us to machine an extremely small bearing gap for
superior platter stability. Secondly, since both bearing components are
made from the same material, the clearance between bearing parts remains
unchanged by temperature variations. In bearings made with dissimilar
materials, varying rates of expansion and contraction result in
variations in the stability of the platter. This can’t be controlled
unless a heater is used to stabilize the temperature. Our bearing design
assures consistent high level performance without complicated
compensation systems. And the steel we use is so durable that we
confidently offer a 20 year warranty.
The Spiral Groove bearing incorporates a steel ball and sapphire
thrust plate so the entire weight of the platter rests on the very small
contact area between the ball and sapphire. This spot is vulnerable to
wear and is a source of noise. To further insure the bearings durability
and smooth operation we use a custom designed magnet system that
reduces the weight on the sapphire to about 2 Lbs. This is a major
contributor to its smooth operation and low noise.
Like Strange Attractors, the SG1.2 platter is built with irregular
shapes and carefully chosen materials. The Graphite and Aluminum
assembly provides a non-resonant surface for the record to mate to.
Energy transfers quickly from the record through the platter and is
dissipated internally. A 14 inch stainless steel drive ring provides the
inertia of a much heavier platter. The speed stability it provides can
be heard in the SG1.2's rock solid sound stage. Our simple and reliable
clamp assures close contact between the record and platter surface and
helps flatten warped records.
Our arm board has a lovely twist, so to speak: the SG1.2 arm board is
fitted with a stainless steel bayonet mount. With the push of a button
and a slight twist like a camera lens, it is easily removed from the
turntable. This unique system provides the enthusiast fast and easy
arm-and-cartridge swaps with accurate re-attachment. Once a cartridge
and arm are set up and adjusted, detachment and re-attachment with the
bayonet mount provides solid, locked-in, perfect alignment every time.
The extremely low residual noise floor of the SG1.2 reveals not just
nuance, but sheer clarity. It breathes both low level and high level
dynamics more convincingly. With very controlled authority it reveals
low frequency extension and drive that is felt as well as heard. The
SG1.2 exudes an authoritative calm that is a window into the soul of the
performers. By removing itself from the equation it lets the vinyl—and
only the vinyl—do the talking.
SG 1.2 Features and Specifications
- Oversized stainless steel platter drive ring for increased inertia and speed stability
- Inverted sapphire disc/hardened steel polished ball bearing for silent, long wear
- Platter driven at rotational plane of bearing for wobble-free rotation
- Spindle de-coupled from bearing for optimal mechanical isolation of record
- Magnetic levitation system to reduce platter weight on the sapphire thrust bearing
- Graphite and aluminum platter
- Low durometer round belt
- Quick-change bayonet mounted arm board
- Electronically selectable speed control with fine adjustment: 33⅓ & 45 rpm
- Low voltage/high torque AC synchronous motor with proprietary phase control to eliminate cogging.
- Adjustable, decoupled, aluminum and graphite feet
- Dimensions: 18.5” W x 15” D x 4.5” H
- Weight: approximately 80 lbs.