Just confused

Hi I am fairly new to using high quality audio equipment.  I have assembled all of the gear I want for listening/enjoying the music.  Of course it’s only a matter of time before you ask yourself “What if?”.  I understand that room acoustics matter so I am off trying to implement acoustic panels - some good relatively consistent advice here.  What I struggle with is the subject of vibration control/isolation ... the advice from the community is not very consistent.  The floor in my listening room is slab cement with ceramic tiles on top.  I have Avant-garde Uno speakers (with spikes since that is they way they came), REL subs (rubber feet) and effectively an unbranded equipment rack (with spikes).  Are spikes what I should remain with for this kind of surface?  Does it make more sense to decouple the speakers and rack from the floor with some kind of isolation device?  Should I be replacing the current metal spikes with “cones” (or other device).  Should I use the same device for speaker and rack?  I just want to avoid shelling out a bundle of money for something that may turn out being a negative.  Thanks in advance for your patience with my naive questions.
Try a large enough rug to place under the speakers and far enough in front of them to address first reflections from the floor.

If a smaller rug is the only option...place this in front of the speakers to address first reflections from the floor. Buy some brass footers for your speaker spikes. These are little saucers with an indentation in the center to cradle the spike. I cut out some leather circles to place under the brass footers to prevent the odd buzz from an uneven wood floor.

The most important thing is just to try stuff on your own. Read a couple of good books on acoustics/speakers etc.. This helped me quite a bit.

I’ve just been thru this. Concrete slab floor is great for vibration control. Rubber feet sounded much better than spikes. Might be because it’s hard to get 4 spikes perfectly balanced on concrete with zero movement. They always rock a bit. So, I put the factory feet in instead of the spikes. Yes.  I tried various isolation feet. No. I even tried springs because some people here think that they are the ultimate isolation medium- capable of isolation below 5 hz I was told.  No.  Loss of bass definition.  For acoustic control purposes I decided to put down carpet and pad along with other room treatments. Yes. Huge improvement.  But, I felt the bass definition could improve. Back to spikes thru the carpet and pad. Yes! I’m very happy.  And they don’t rock at all. I can’t explain that part. Carpet shouldn’t make a difference when I know the spikes go all the way thru. That has been my experience in my room. I’m not saying I think my way is what you should do. I think every room and system is unique. I had fun trying things and seeing what worked. I hope you do too. If I spend too much more time isolated in my house I might go crazy and try bolting the speakers to the floor.  🙃
I wouldn’t spike anything to concrete/tile. I use Herbie’s Audio Lab sliders under my speakers on ceramic tile they work great and you can tweak your speaker position much more easily. 
I even tried springs because some people here think that they are the ultimate isolation medium- capable of isolation below 5 hz I was told. No. Loss of bass definition

>>>I actually don’t believe you. Springs would only work directly under relatively lightweight speakers due to center of gravity issue. And you would have had to match the spring rates to the load which I doubt you did. For speakers you don’t need to get down below 5 Hz because the speakers don’t produce any frequencies below 20 Hz. The objectives of speaker isolation are different than for components - for speakers you’re preventing mechanical feedback. If you tried to achieve a Fr of 3 Hz for speakers the springs would have to be so “floppy“ the speakers would fall over. And if the springs are too stiff they won’t isolate effectively. I suggest we write this off as operator error.
Fortunately I experienced it first hand, and therefore there was no scepticism in my way to overcome.

Opinions vary, however I will attest to correct spring rates for the mass they are isolating absolutely do work in effectively cleaning up unwanted distortion and vibration to and from each loudspeakers, and into equipment.

If someone interested here cannot source well designed isolation springs, [ I thought someone here on Agon was selling some cryoed springs? ].
Otherwise I have a source, you will need to supply the weight of the device/s to get the appropriate spring rates etc. They are inexpensive.

Compression springs isolate on both vertical and horizontal directions simultaneously.