[rcag_ils]

Anyone has any experience with this magnificent looking plinth? I have one and will be used for my Thorens 125 project. It looks great, just not sure if it would offer any sonic improvement.

[neobop]

Anyone has any experience with this magnificent looking plinth? I have one and will be used for my Thorens 125 project. It looks great, just not sure if it would offer any sonic improvement.

Why, is something wrong with the 125 plinth?  Want to mount 2 arms?

Seems like it has great potential to degrade and will take lots of work to improve things.  Giant hollow box made from 15mm MDF.
Here's a beauty shot:




http://www.vinylengine.com/turntable_forum/viewtopic.php?t=44811

http://www.audiokarma.org/forums/showthread.php?t=426205

neo

[rcag_ils]

Nothing wrong with the 125 plinth, just want to do something different and resurrect this vintage SME product. The "giant hollow box" is a myth, the top is isolated from the base itself.

[neobop]

I'm going by the users comments and photos in those links.  There are more threads about the plinth in various forums. 
It will take a lot of work to make a great sounding table out of it, and you will have a lot of hollow space. 
Hollow spaces in a plinth are like the insides of a drum and make a good resonant chamber.  If you treat it like the insides of a speaker box, use internal bracing and fill empty space, it should be much better. 

The plinth looks like it would have the potential for a table with 2 or 3 arms.  I'd figure it out first with the platter unit placed off center to the right, and a conventional 9 or 10" arm there.  If you place the platter slightly forward you could easily accommodate another arm in the rear with the pivot to the left.
That's a traditional layout for a 2 armed table.  Maybe you'd prefer something different.  I'd use steel corner braces sourced at a hardware with washers to prevent the screws from going through.  You could use wood braces instead - glued and screwed.  Long braces going the width and depth of the plinth are also recommended.  Then fill up any empty spaces and you'll have a 2 armed battleship of a table. 
Good luck.
neo

[rcag_ils]

Back in the days, SME made this plinth to accommodate various popular turntables, and the Thorens 125 was one of them. The top plate was pre-cut to fit the 125 perfectly and isolated by 4 springs and foam pieces in the corners.

There's really no more room to fit anymore arm. Basically the table is isolated by the plinth's 4 springs, then the platter is further isolated by the table's original 3 springs. I also have the original SME 3009 arm.

Bracing the plinth will be a task since some of the space will be occupied by part of the table, the corners already braced and supported by wood in the factory.

All I need now is a new motor for the table.

[neobop]

Have you read some of the threads by people who actually use the plinth?

From the Karma link above:
"I have removed the springs and now performance is fairly OK with my TD-125, but remember than the 125 is a suspended turntable, so results do not depend too much on the plinth."

"It's a resonant box, with the added feature of a suspension for the motor board. The result is everything bad that can be done for mounting an idler wheel table. It was known in the late '60s when the plinth was designed that idler decks needed to be mounted to a solid base to reduce noise, yet for some reason everyone jumped on the wobbly bandwagon."

"It is huge though, and if you get an uncut motorboard you could probably mount more than one arm, including a 12". I saw a post on one of the UK sites (I forget which) where a guy replaced the motorboard with slate. Maybe that'd work better."

Good luck with the plinth.
neo

[rcag_ils]

Yes, I've read some of the posts.

Basically they said SME screwed up on this plinth.

[neobop]

You could make it work, but I think you'd have to customize for the particular table and you're going to have some figuring to do.  With a deck that already has a suspension, you have to defeat the plinth suspension.  If you want to use the plinth suspension with a non-suspended deck, then the center of gravity should be such that it bounces straight up and down. 

Any way you look at it, it will take a bit of work and I think it would benefit from replacing the entire top piece with something like reinforced acrylic. You could make some kind of frame for the existing top piece and even design removable armboard to change arms.  Does yours have cut outs for the 125 ?
neo

[rcag_ils]

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