Could we improve on the solid timber method by finding another material which incorporated the natural inherent damping of wood but with a higher degree of rigidity and mass?

The answer was not easy to find but, when discovered, proved to be ridiculously simple in concept. Welsh Blue Slate is a naturally occurring material that has unique properties (the 'Blue' description is to denote the slight 'blued' sheen and grain seen when highly polished; the natural colour is a dark grey). Unlike other 'hard' rocks, slate is formed from multiple sedimentary layers which avoid the consistency of granular structure in volcanically formed stone. This makes it easy to 'shear' to form the thin slate that we see on our roofs.

There are many forms of slate, however, and not all are as brittle or easy to split as roofing slate. Welsh Blue Slate is the 'king' of the slate realm, presenting a hardness and solidity that makes it amenable to carving. For our use it ideally combines the functions of rigidity, structural integrity and critical damping that we are looking for in a plinth. And it has the undoubted advantage over wood in that it possesses very high mass.

Bolt the cast chassis of a Garrard 301 or 401 to a slab of Welsh Blue Slate and motor vibration is quelled, instantly. The pressed steel chassis of a Lenco is even more dramatically 'quietened'. You only need a 20mm (3/4") slab of slate to achieve this, however you can get further gains in sonic quality by a) increasing mass and b) providing an isolating base.

The purpose of the twin tier plinth, which offers the ultimate performance from idler drive turntables, is to provide a 'ground' on which the turntable plinth sits. This slate base improves stability and provides a level of isolation to reduce the effects of support and building related interference feeding through to the chassis and, therefore, the platter and record.

There is a further advantage to the twin tier system for the Garrard 301 and 401 and that is a separate Pickup Arm Carrier to accommodate different lengths of arms, for example SME3009 or SME3012. This Arm Carrier is similarly machined from 30mm thick slate and sits on three spiked feet which locate onto the isloating base. This effectively removes the pickup arm from any remaining conducted vibration present in the chassis and top plate revealing a level of clarity and reproduced detail that is simply stunning in its precision and lucidity.

But you don't have to go as far as the top-of-the-range twin tier plinth to appreciate the quality of the Slatedeck design. Even the 20mm single layer plinth outperforms other CLD designs in providing the correct, high mass, termination that the designers of these classic turntables intended. Fully precision machined to suit your turntable, the Slatedeck plinths are an ideal solution to classic turntable housing.

Each plinth is supplied with gold plated adjustable feet for levelling, and a bottle of polishing oil that you can apply occasionally to reveal the beautiful, natural grain of the Welsh Blue Slate. With its polished surface and gently rounded edges, the Slatedeck plinth is a delight to the eye and forms an attractive centrepiece to your equipment collection.

Next - Slatedeck's Adjustable Armboard