Springs under turntable


I picked up a set of springs for $35 on Amazon. I intended to use them under a preamp but one thing led to another and I tried them under the turntable. Now, this is no mean feat. It’s a Garrard 401 in a 60pound 50mm slate plinth. The spring device is interesting. It’s sold under the Nobsound brand and is made up of two 45mm wide solid billets of aluminum endcaps with recesses to fit up to seven small springs. It’s very well made. You can add or remove springs depending on the weight distribution. I had to do this with a level and it only took a few minutes. They look good. I did not fit them for floor isolation as I have concrete. I played a few tracks before fitting, and played the same tracks after fitting. Improvement in bass definition, speed, air, inner detail, more space around instruments, nicer timbre and color. Pleasant surprise for little money.
noromance
@noromance
I used leftover Nobs springs directly to good effect.
Those Nobsound springs are quite small, aren’t they? If you play with the search tool on the Century Spring site, you can find larger diameter springs that may suit your needs, which should improve stability. The springs I used under my subs are 1.75 inches in diameter and the springs under my main speakers are 1.625 inches in diameter. I am looking at their S-3031 springs for my general electronics, which range from about 20 to 30 pounds each in total weight. OD of those springs is almost 1.3 inches so they should be quite stable. The free length is 1.0 inches and compression rate is 20#/inch so compressed at 5 pounds they would be 3/4 inch long in service. They are good for a maximum of 12 pounds each. This seems to offer a good, wide range size for my electronics, which are also somewhat mass loaded so total weight per spring will probably range from about 6 to 8 pounds. Unit price of the stainless steel S-3031 is $5.63 each so in the audiophile world that is a relatively benign $22-$28 per component. In comparison, Herbie’s Tenderfeet are $14 each.  If you order, make sure you get closed/ground ends.
@frogman 

+1. You may remember me talking about my many experiments with my VPI mkIV.

I ended up using Symposium Rollerblock Jr's in place of the springs. It was a revelation!
This concept of "zero stiffness" is interesting.  I have been reading the paper that was cited above.  It seems in fact to be a theoretical ideal rather than a truly attainable state. But that's OK as a guide. From my experience with turntable supports, the Minus K comes closest to zero stiffness.  If you can achieve what the Minus K achieves using only inexpensive commercially available springs or modified springs, you are a very patient person.  I would still have more than reservations about seating a speaker on a support that had zero stiffness, especially in the horizontal plane.