I use Aerial SW12 subs which are heavy, over 100 lbs each. The best thing I’ve found at a reasonable price are NoboSound springs. They’re about $35 per set of 4 the last time I looked.
I have a suspended hardwood floor and always had issues with pickup on my vinyl rig from low bass notes, until I added the springs. I’ve tried various other devices including spikes, cones, cork pads etc. The key is that you want to decouple the subs from the floor. Using spikes has the opposite effect.