If you look at the Townshend videos on You Tube there is one in a convention hall..and after they suddenly Cutaway from Jumping Jack Flash they show the speakers side by side..One speaker on the podium and one on points...there is 0 noise on either display. No seismic noise that day?
Here is one, where you can clearly see there is a low noise level on both, maybe slightly more on the spiked speakers on the left. https://youtu.be/7ew4dRUEm-k?t=30 But that is not the whole point. As has been stated many, many times, the main benefit is to remove ringing with the floor thereby allowing the speaker cabinet vibrations to dissipate out much faster for the cleaner clearer sound everyone reports hearing. Watch the video it is perfectly clear.
Here’s another one https://youtu.be/BOPXJDdwtk4?t=27 You can see quite clearly there is some background noise on both speakers, just a little more on the spiked one on the left. You can even see the one on the left make a little blip before Max stomps. just from moving his foot getting ready to stomp.
There’s a whole bunch of these. If you have one showing dead flat make-believe like you are saying please provide the link so we can check it out. I would sure like to see it.
This is so clear and easy to understand, especially for a guy as otherwise sharp as yourself, I kind of want to think you are trolling.
One thing I will say, the name Seismic put me off for a long time. Yes there are seismic vibrations and yes they probably do have some impact and yes these things are designed to filter out those sorts of vibrations. But the name is misleading in the sense the seismic part is a sideshow. The real benefit is eliminating ringing. That is what really accounts for all the great improvement everyone is hearing. Maybe that is what is throwing you off the way it did me?