Forgot to mention one more thing - make sure that the speaker placement is as precise as possible. While adding the spikes, the left speaker moved up 3/4 inch up, when measured from the back wall (compared to the right speaker). And that messed up my center vocal positioning. I went nuts for 2-3 days before I used the measuring tape to find the issue. Once fixed, the image snapped precisely in the middle. So, yes, the spikes improve the sound, but be careful with that speaker positioning.