Stage volume simulator?

[20db pad]

Anybody remember who makes (or made) a pad or platform that a bassist could stand on which simulated the vibrations a player would experience on a large stage at high volumes? It was supposed to be used in situations where stage volumes were to be kept low, possibly in tandem with in-ear monitors.

No plans or interest in buying one, just having a brain fart/senior moment

 

[superbassman2000]

I remember there was a product called the "buttkicker" but i recall you needed to buy a separate poweramp for it, so it got expensive