Hi Ait,
This topic was one of the most contentious ones during the late Winter and early Spring of 2000 - when the original Teres project was its most active. In December, 1999 through January, 2000, the original Teres-5 worked through the basic parts design, after which point we frozen the design and invited the "public" into the project. It was at this point that peoples' attention turned to the design of their bases - having some 5 months' time before the delivery of their parts.
There was a split into two main camps, which someone (I think it was Ken Schei) designated as the "stiffies" and the "woodies". Of course, those of our friends from the British Isles would contend that a woodie is a stiffie, but I digress ...
The argument espoused by the "stiffies" was that although the frequency of a rigid piece of metal is quite high, and centered in the most sensitive area of human hearing, that this problem is negated by our good ol' friend the RIAA curve which attenuates high frequencies. They further argued that these higher frequencies are lower in amplitude and are easier to damp. Their approach in general centered on working from a perspective of damping a ringing substance and letting the RIAA equalization deal with the rest.
The "woodies" favored damping over rigidity, and for the most part they didn't work much at stiffening their bases. Their philosophy centered on using a material which could not easily be excited. The argument against soft, lossy bases has centered around its poor dimensional stability (both thermal and mechanical), combined with the additional challenge of draining vibrations away from the bearing due to the dissimilar materials interface (e.g. brass bearing --> wood base). The more similar the material interface is, the more vibration is transmitted and the less it is reflected.
We all know the different directions taken by both the DIY-ers as well as by Teres / Galibier / Redpoint, and it doesn't bear repeating here.
Because yours is a DIY project, I would advocate a flexible architecture which would allow you to experiment - adding a thin sheet of aluminum (ca 1/8" to 1/4" thick) to the top surface. If you go modular, you can experiment to your heart's content. You may not be in a position to generalize your knowledge and your discoveries beyond the context of your own turntable, but the good news is that it will be your design and will suit both your listening tastes as well as your system.
Cheers,
Thom @ Galibier
This topic was one of the most contentious ones during the late Winter and early Spring of 2000 - when the original Teres project was its most active. In December, 1999 through January, 2000, the original Teres-5 worked through the basic parts design, after which point we frozen the design and invited the "public" into the project. It was at this point that peoples' attention turned to the design of their bases - having some 5 months' time before the delivery of their parts.
There was a split into two main camps, which someone (I think it was Ken Schei) designated as the "stiffies" and the "woodies". Of course, those of our friends from the British Isles would contend that a woodie is a stiffie, but I digress ...
The argument espoused by the "stiffies" was that although the frequency of a rigid piece of metal is quite high, and centered in the most sensitive area of human hearing, that this problem is negated by our good ol' friend the RIAA curve which attenuates high frequencies. They further argued that these higher frequencies are lower in amplitude and are easier to damp. Their approach in general centered on working from a perspective of damping a ringing substance and letting the RIAA equalization deal with the rest.
The "woodies" favored damping over rigidity, and for the most part they didn't work much at stiffening their bases. Their philosophy centered on using a material which could not easily be excited. The argument against soft, lossy bases has centered around its poor dimensional stability (both thermal and mechanical), combined with the additional challenge of draining vibrations away from the bearing due to the dissimilar materials interface (e.g. brass bearing --> wood base). The more similar the material interface is, the more vibration is transmitted and the less it is reflected.
We all know the different directions taken by both the DIY-ers as well as by Teres / Galibier / Redpoint, and it doesn't bear repeating here.
Because yours is a DIY project, I would advocate a flexible architecture which would allow you to experiment - adding a thin sheet of aluminum (ca 1/8" to 1/4" thick) to the top surface. If you go modular, you can experiment to your heart's content. You may not be in a position to generalize your knowledge and your discoveries beyond the context of your own turntable, but the good news is that it will be your design and will suit both your listening tastes as well as your system.
Cheers,
Thom @ Galibier