DIY Turntable....

...coming on nicely. Just got to get a motor and PS sorted (hence the wait for more money!). After so many useless motors I am going to go for a brand new LP12 job as I am using a Linn subplatter. I am going to go with belt drive for the momment but with the possibility of converting it to idler drive.....not sure yet, I would have prefered a more powerfull motor if going that route, we'll se what it sounds like first.

Main plinth is made up of 4 layers of 18mm birch ply and is veneered with burr oak. I am still looking for some suitable (soft) isolating feet that are adjustable.

Outer platter is a Thorens TD160, much cheaper than a Linn item. The center needed releiving slightly (wet and dry did the trick) and I will have to make the level up with the mat as it sits too low on the Linn sub platter.

Sub platter is 2 bits of 12mm acrylic and it sits on some carbon isolators. The motor will be mounted directly on the birch ply plinth thus hopefully giving decent isolation but with a nice direct drive path. The motor sits closer to the sub platter than on a LP12 so I will have to sort out a shorter belt.








Paul.

 

Wow! thats looking great

 

Looks great.............fantastic work!

the down side is your "isolaters" are couplers.....if I'm not mistaken.

They look like carbon fibre feet and brass spikes these will channel energy not isolate. I'm not saying it won't work but it could be a problem area.

you could keep the motor in its own pod isolated from the chassis using a lage hole to the tt support...not ideal. or get rid of the solid coupling and use a compliant medium or springs or oposing magnets...

I may of course be barking up the wrong tree! but you did say isolators......

 

I called them isolators as that is what the manufacturer call's 'em! Dont know what they do or how they work, I used them as I had them knocking about and they didnt cost anything!

Seriously, I find it dificult to get my head round some of the more technical aspects most of the time so this is down to good old trial and error. You can see a reccess around the carbon cups and the outer edge of the plinth well, my idea is to fill this with something to absorb and sink vibrations from the sub plinth, probably a sand/lead/epoxy mixture.

I did consider some kind of "suspention" but wanted to try a solid design first, speed stability being my main initial target. We'll listen to how this one sounds and take it from there

 

Paul,
A solid design should be absolutely fine so long as it is on a decent support, maybe a wall shelf.
I would be very careful with use of magnetic isolation in close proximity to a cartridge.

 

Also, why not have the outer platter skimmed on a lathe to make it match the Linn inner platter?
I know it may be against the DIY aproach, but would possibly be better and/or easier than tryint to sort the discrepency with a mat.

 

No ...thats great and I agree most engineering is trail and error , though most would not admit to it !

you could mass line the whole of plinth "cup" using layers of bitumen sheet...this is a deadening material and quite massy.

Penance is right you will need a wall support or similar other wise foot falls may be a problem or if you have a solid floor other external vibration or traffic noise.....not knowing your particular circumstances.