A Copernican View of the Turntable System

Hi Henry- you stated and I agree with this concept based on what I am hearing so far.
"I believe both turntable and arm pods should be 'coupled' in the same way ie all spikes.
I don't believe you should have spikes on the arm pods and pliable footers on the turntable OR vice versa."

Both my sp10 and ET armboard are on spikes. However.

I am also thinking if you are able to isolate the Platter/motor and armboard "properly" then this should not matter "as much" ?
If someones specific combination works in their system/kit it should be evident in what you hear - which is what matters not the concept.

This project has provided me with very neutral,distortion free sound - meaning to me no pronounced highs or lows, followed by what I have found to be a very strong desire to... and be able to - turn up the db as Dgob stated in an earlier post and enjoy the music immensely. Isn't this last sentence the PROOF "for me anyway" if certain projects are heading oneself closer toward "shangri la" in this hobby ?

My listening since implementation has been at a higher db. I'd like to go higher still but my family doesnt allow it. I need to spend more $$ first isolating my sound rooom better :).

Curiosity killed the cat - I put a wanted ad out for those AT616's and someone from Denmark replied and well I now have a set coming to me to try out this theory different feet on TT and armpod/board. I want to hear how it changes things up. Will let u know.

Hi Dgob

How heavy is the Acoustic Signature arm board that you are using and I am curious what type of center clamp you are using on your sp10 ?

My ET 2.5 armboard weighs more than the sp10 itself.

The next one will be made of brass and I will ensure it weighs more still. I feel the weight on the spikes is critical for isolation.

Dear Thuchan - thank you very much for your cartridge recommendations for my ET 2.5 arm.

Cheers Chris

At low volume levels its not that hard to get a 'table to sound good. Its at high volumes where the rubber hits the road. IMO, the turntable should be unassailable at any volume. I found that once I had sufficient mass and rigidity in the plinth, that that helped, but I also have the 'table perched on an Ultra Resolution Technologies platform, which is one of the best passive platforms I have seen, unfortunately no longer available (and stupidly expensive when they were!).

The platform is in turn set up on a Sound Anchors stand that is custom-built to accommodate the platform. In turn the stand is mounted on 3 Aurios-Pro bearings.

My point is that it is hard to really know what is the plinth in all this. The only decoupling that occurs is the platform itself and then between the platform and the stand, that is my 'suspension' so to speak. The platform is quite heavy, rigid and inert as it is a sandwich of a special grade of marble, high tensile steel and a military-grade constrained damping layer.

Vibration and resonance can be quite insidious in a turntable, so with respect to the anti-vibration platform, the platter and now (in the case of this thread) the arm tower, it is likely that it would be really difficult to go overboard on the whole thing.

Points in use under the platter and arm tower, while being mechanical diodes so to speak, are not actually perfect diodes. Like elastomerics, they are more efficient if they are loaded properly! So if the load on them is underpar, they simply will not work so well. Load up that arm tower! Get some mass on it, so the points can do their job.

Dgob, Decouple all that you want. My point was or would have been that it is perhaps not wise to use very different mounting systems for the tt and arm pod, e.g., spikes on one and AT feet on the other. In that situation, the two separate devices are almost sure to have a different response to external sources of vibration, and, in keeping with my private belief system, we do not want the arm/cartridge and the groove on the LP to be moving in different directions, whilst the stylus tries to do its work. Surely you can see that this might not be a good idea. This reminds me of the old SNL commercial spoof, where the rabbi tries to perform a circumcision in a car driving over a rough road.

Chris/Halcro,

Thanks for your suggestions and I will look into having a heavy arm column produced that may work better with the spiked option. The weight limitations with the Mambo column could be where the problems lie and it'll be fun (and, hopefully, rewarding) to try this out. I'll let you know as soon as I can sort this out.

On the issue about both the TT and arm tower being on spikes I think Chris has hit the nail on the head. If you are seeking complete isolation, the different methods are secondary. The question resides in how effective both methods are at controlling resonance and vibration.

Henry, if you get a chance to try out the AT616 footers you might be surprised - I was. This also offers you the potential to truly decouple arm-column and TT, which was where I came in, as it were. Lewm, I hope that answers your scenario.

Atmasphere,

Thanks again. I'm going to load up the arm tower as soon as I find a local engineer able to undertake this for me.

On frequency extention, I'd hasten to add that I am playing this set up at very high volumes and the quality needs to be heard to be appreciated. So as I said, I think for everything to click into place I will follow your, Chris and Henry's suggestion of building a heavy arm tower. The gains I already have with the current approach to decouplling makes this a more than worthwhile endeavour.

Grateful for all your kind suggestions and contributions.