OK, the measurements only took about 15 minutes, I suspect writing this post may take longer.
I placed an accelerometer on the amps top (Onkyo NR5010 in the theatre room speakers are Usher BE718 with paradigm sub12). The amp is sitting on 20mm mdf shelf with a reinforcing bit of ali angle cos the amp weighs a tonne. Nothing sophisticated in any way. Concrete floor, brick walls.
The first problem here is that if you are not familiar vibration or its terms the plots could be a bit meaningless. So what I did first was take two measurements that put put some context into this for people. 1st was tapping the amp top gently, second is dropping a tennis ball on it multiple times from a height of 10 cm. Both minimal vibration inputs. All plots are provided in velocity and acceleration.
Dip in and out HERE