Turntable platforms

Same thing with components as with turntable
4 curtain rings 
4 racquet balls 
place feet of components centered on the racquet balls 
vibration gone
done
or you can place granite in the racquet balls then your components
an engineer shows me this 30 years ago

 I use Minus K under my turntable and tube amps, they work well, no pumps and hoses to deal with, just science. I think they have a new model which is thinner in profile, yet does as good a job as the taller units such as I have. My Turntable is a Technics SP-10MK2 with an OMA plinth, it weights 200 pounds.

 I live in a wood framed building, wood suspended floor, it was impossible to play records before the Minus K because of the feedback issues. I tried granite + sandbox to no avail.

For cheap DIY dudes here’s one for the ages. Three Super Balls - the 3/4” size, not the bigger 1” balls - like they have in vending machines - and three Snapple bottle caps. The Super balls are great because they don’t store energy, they release it rapidly. That’s why they bounce so high.