Removing spikes... Now my speakers sing

I think the issue you are having is rocking.

One thing everyone with medium weight speakers should try is adding mass to the top of the speaker, near the front. It reduces the ability of the woofers to rock the cabinet back and forth. Spikes make this tilting easier.

Best,
E

Stillpoint 5's under my Wilson Sophia 3's couple the speakers to the wooden floor, making the whole listening space resonate. 

To reiterate getting all FOUR spikes to carry the weight equally is very important, no matter the flooring. Carpet, tile wood..I used to used a set of slippery thin samples. I would set them under each foot and pull. I knew when the weight was equal by feel of the pull. It is just one way to do it.

Three points determine a plane. Four points do not necessarily determine a plane. That’s plain old plane geometry. Thus, oft times three cones will be less wobbly and sound better than four. For tall heavy speakers four cones can be a little dangerous inasmuch as if someone accidentally bumps into them they can fall over. Which is why large footprint boards should be used under the speaker with the cones under the board. Much more stable.

audiosens

General rule to couple (spike) or de-couple (not spike) speakers to the floor, comes down to what floor you have.

1: Cement slab floor on mother earth (not cement sheet) = spike (couple)

2: Suspended floor wood, sheet, (includes cement sheet) = no spike (decouple)

If you spike a speaker into a suspended floor as in 2, you transfer the bass of the speaker into that floor, making it a sound board for the bass and ruining it.

Cheers George