Springs under turntable

@mijostyn 

For people whose woofer driver carries a substantial amount of the midrange a higher crossover is a large advantage lowering distortion in the midrange. This is typical of two way speakers.

To achieve the reduction in distortion you described would require the main speakers to be crossed over above the low bass frequencies, using something like a high-pass filter, correct?  The benefit occurs by allowing the low frequency driver (especially in a two-way) to mostly operate within its optimal range of excursion without being required to try and reproduce both midrange and lower bass frequencies.  

I just fixed my brother in law’s turntable with the same issue, but the rubber on his had disintegrated. I found these https://www.mnpctech.com/collections/turntable-lsolation-feet and installed them without any issues.

@mitch2 , you are exactly correct. Low bass pushes the suspension into it's nonlinear zone. Then there is doppler distortion on top. 
If you have at least two subwoofers of high quality you can push the high pass filter up as high as 150 Hz. Imagine doing that to K horns. JEEZ!

I chose the easy way out for my full size, 185 lb. speakers using spikes.  I have a custom listening room with 12" thick, steel rebar reinforced, 3000 lb psi poured slab.  At least no vibrations are going from the floor up, possibly only the speaker itself vibrates.  I like Townsend platforms and springs, possibly for my next speaker.

I use the Townsend Seismic Sink (bladder) for two decades under a VPI TNT VI+ turntable.  Without it, I would have junked the table as it has poor vibration control with those fancy feet.  

For the rest of my equipment, I use various versions of Stillpoints (ultra-minis, SS) and they work great after testing out a dozen others (some were equally good, most worse, none better).  I also use a buckwheat pillow under an EAR 324 phono preamp and CD recording/editing machine (better than anything else, inelegant and very inexpensive).  The buckwheat pillow is rather good overall; however, I wouldn't use it near my tube equipment (heat).  

@fleschler ,

Did you get the buckwheat pillow idea from Tom Port?