Townshend Pods under TT Don’t Do

@jasonbourne52,

Not at all.

Max Townshend's original Seismic product (the Seismic Sink) was an inner tube (or two, or three, depending on load rating) between two metal plates. For years I used them, only replacing most of them when Max introduced the Seismic Pod. I had tried the Mod Squad Tiptoe in the 80's, and was amused that there were people who considered it (and it's imitations) an isolation device, rather than a coupler, which it of course is. As are spikes.

The first time I heard of the idea of inner tube isolation was in the Frank Van Alstine newsletter, published in the mid-80's on. He suggested the inner tube be placed between two cement paving stones, or their equivalent. The Seismic Sink used damped steel plates, the top plate folded over to hide the inner tube. Bright Star made a similar product, using painted MDF in place of the Sink's steel.

A single inner tube doesn't take into consideration the mass distribution of a component (for instance the transformer side of a power amp), so can be somewhat unstable. The Seismic Pod may be used in combinations of different load ratings, to balance an uneven mass load. Very flexible.   

The biggest inner tube I ever used, the outside diameter was about 5 feet. Four or five of us laid on it and went down the Paradise Run at Mt Rainier like some kind of hovercraft. All of us beautifully isolated from the violently undulating snow berms down to but a few hertz. Yes the fundamental frequency was that low. And you wouldn’t think it, but in this case I am happy to report, with plenty of amplitude!

@joenies,

I am glad that you experimented and tested springs under your non suspended turntable because now I don’t have to. I also have a heavy mass turntable (Transrotor Apollon 80MM TMD, roughly 130 pounds with three external motors) resting on a nearly 300 pound Clearaudio MontBlanc turntable stand (columns filled with concrete), on a concrete basement floor with stranded bamboo. 

I would like to know what issues you are trying to resolve or if this was a matter  of experimentation? I can knock on the turntable stand and I don’t have any resonant sound getting picked up on the tonearm (who does that when listening to music anyway?), and I am also not getting feedback from excessive loudness from music and bass. It’s not happening, dead silent, so I don’t even think about adding suspension or suspending the turntable because I am completely satisfied with the performance  based on the aggregate of the design parameters of the entire system. That is what is key here, synergy of the entire turntable system. 

Herr Reike from Transrotor has designed some really nice turntables over the years and acoustic feedback elimination is part of that recipe going into the design and build of many Transrotor turntables. Here is a nice video explaining the build details of Transrotor. https://www.youtube.com/watch?v=L38cZ0Bj-Ys


That is why I never bothered to concern myself with the idea of adding a suspension system under my turntable which is built under the principal of being unsuspended. 


A few of my Deutsche audio friends scoff at the idea of adding complexity to an already rigid system combined with mass loaded racks etc, which help to ameliorate many floor and vibration issues. They rationalize that the precision of the design and noise reduction of the combined materials make for a very quiet platform to start with.  I guess at the end of the day, tomato or tomatoe, whichever solution works best for each individuals system is best for them, but not best for all. 
Thanks for the feedback on your attempt of using a suspension system under your mass loaded turntable. It is good for some, not so for others. 

I had no issues with my TT. After reading many articles and post about how great the springs are, I thought I would try them.
my TT sounded very good to my ears, just wanted it to maybe sound better. That plan didn’t work out for me.
My TT is back on the rack and sounding good again and the plus is I don’t have to sneak up on it to make changes.
@audioquest4life 
very nice analog setup you have.