Isolated Arm Board

Isolated Arm Board

Perhaps “arm board” is too pedestrian a term for the sophisticated structure that supports and Obsidian’s tonearm; “arm suspension” seems more appropriate.

Key to the function of the suspension is the sheer mass of the mount itself. Because the ratio of the mount’s mass to the motive force of the stylus is so large, the mount is no more affected by vibrations transmitted from the stylus through the tonearm than an elephant would be by a sparrow landing on its back. Because of its high mass, it is also effectively immune to ground- or airborne vibration.

The energy sink provided by the mount would be impressive in most turntables, but it still wasn’t enough for our dream team, who took the extra steps of double-isolating the mount using components made from tungsten, a metal that is 1.7 times as dense as lead and thus allowed our designers to achieve much greater mass in the same amount of space. Tungsten is used in the arm post and in the contact points for the arm suspension.

The entire arm mechanism is magnetically attached to the base of Obsidian, using tungsten contact points rather than fixed mechanical fasteners such as bolts or screws. In a sense, the mechanism floats on these tungsten contact points. Any energy flowing from the base to the tonearm, or from the tonearm to the base, must first make it through the tungsten suspension system. Which, for all intents and purposes, simply isn’t going to happen short of an earthquake.

The position of the mount is adjustable to accommodate practically any size of tonearm.