I do own a VPI classic 1 but, not the SDS controller. I am powering my classic 1 with the purepower 1050 AC regenerator. The purepower unit does output a true 60hz/120v feed. I haven't detected any flaw in speed stability so far. If it is off speed I can't detect it audibly. I would like to try the SDS to see if it would make an improvement.
The reason I responded to this thread is beacuse I have just ordered some terrastone products and thought I would share what information I know about the material. According to Dan @ edensound, Terrastone material is a very dense isolation polymer. He said it serves a dual purpose of rejecting outside vibrations as well as damping vibrations originating from the source component. I'm not sure exactly how this is achieved, you would need to ask dan about that.
I tried some of dan's brass bearpaws on my classic one. They did make a very noticeable improvement but, I had some low frequency vibration problems due to the rigid setup. Dan suggested the terrastone because it does a better job of isolation than the brass. I have ordered a custom terrastone platform and a set of terrastone footers for my VPI table. I will post some pictures and my impressions of those products after I integrate them into my system.
I would assume that the terrastone polymer would do a great job of isolating the SDS unit as well. I can't understand how isolating the SDS could improve the sound though, as it is a speed controller and is not directly in the audio signal path. I'm am not saying it doesn't work, I just can't understand how. I guess don't knock it till you try it.
The reason I responded to this thread is beacuse I have just ordered some terrastone products and thought I would share what information I know about the material. According to Dan @ edensound, Terrastone material is a very dense isolation polymer. He said it serves a dual purpose of rejecting outside vibrations as well as damping vibrations originating from the source component. I'm not sure exactly how this is achieved, you would need to ask dan about that.
I tried some of dan's brass bearpaws on my classic one. They did make a very noticeable improvement but, I had some low frequency vibration problems due to the rigid setup. Dan suggested the terrastone because it does a better job of isolation than the brass. I have ordered a custom terrastone platform and a set of terrastone footers for my VPI table. I will post some pictures and my impressions of those products after I integrate them into my system.
I would assume that the terrastone polymer would do a great job of isolating the SDS unit as well. I can't understand how isolating the SDS could improve the sound though, as it is a speed controller and is not directly in the audio signal path. I'm am not saying it doesn't work, I just can't understand how. I guess don't knock it till you try it.