Spikes
"Spikes both couple and decouple the cabinet/speaker output from the floor.
Bass wavelengths are quite long and, below about 200Hz, boundary dependent. Without a surface to travel along they dissipate somewhat rapidly. A woofer would ideally be as close to a boundary (floor) or multiple boundaries (side and back walls, and even ceiling) as possible, or at least a constant distance from them. By elevating a cabinet from the floor with spikes, you reduce the propagation efficiency of bass wavelengths. So, you decouple bass from the room, even if ever so slightly. The effect is quite audible.
Spikes couple cabinet output to the floor, turning it into a transmission medium. Soundwaves travel through many solids much more rapidly than through the air. Instead of "moving the floor", cabinet output is transmitted to the listener ahead of the music, through the floor (made usually a good carrier of sound like wood or stone). This is why I’m no fan of spikes, and the Sunfire people aren’t either.
Try some damping compound between the spikes and the cabinet (not between the spikes and the floor) and let me know if you hear a difference. I’ve seen composite spikes that were metal only on the tips, otherwise rubber. Should work better.
Since spikes do two things I don’t like--diminish bass propagation, and transmit or even amplify spurious cabinet talk--I never recommend their use.
As Sunfire recommends, rubber or other absorbent materials can be used as feet for speakers or subs.
Since a lot depends on the height of the stand and the materials from which your floor is made, why not experiment? Personally I like Dynamat." 1987 or so..
<<<<<<<<<<<<<<<<<<<<<<<<<,>>>>>>>>>>>>>>>>>>>>>>>From the old VMPS web site (Brian Cheney. Mr BASS).. and Sunfire.
35 years ago. Like I said there is a reason NOT use spikes, and I can’t think of a single reason to. Wooden floors can be worse..
Otherwise its just a HUGE drum. 3.5" to 5.5" concrete bounces like a drum.. The dryer it gets the tighter it stretches in a monolithic pour. The worst of the worst.. A slab with soft expansion joints. One slab is different than the next. Decouple always.. Really muddies the bass.. Just a big bass driver (the floor). Very little bass cohesion otherwise.
If Carver and Cheney,(RIP) agree, I’m in their CES winning corner.
Innertubes, spring, silicone pods, YES, spikes NO!! Rubber spikes, how’s that working out.. LOL Charlie Chaplin’s drunk routine..
Opinions.. I don’t think so... Just my self proven and re-proven facts over and over.. I have 2 boxes of spikes.. Even Merlin spikes.. rare from the 30s.. they kinda work.. They are tuned for record player isolation and rumble
Regards