Component isolation

First, anything with a tube.

Next, in order of gain, so phono stage.

TBC, it's a real shame there isn't more research and evidence into vibration and solid state devices. Some gear will be more susceptible to microphonics than other gear just by part selection, construction methods, etc.

That being said, the worst bit of kit I ever had was a cheap phono preamp and it would ring like a bell if you rapped on it.

Much else is probably overblown.

Disregard what Elizabeth said. Each individual component may need very different isolation devices.
Are you asking because you don't want to spend on the devices for all your components or simply curious ?

+1 @inna . Each component may need a different footer or isolation solution. And it usually requires experimentation. 

There are many threads in the archives, some recommending an isolation platform plus footers. In the case of certain components like a TT, it's best to use cones or hard footers to drain vibration into a hardwood platform such as maple.

 

Also agree with @erik_squires . A component doesn't need to have moving parts to cause vibration. There's internal vibration as well as acoustic caused by sound waves.
As stated, anything with tubes needs isolation and sometimes needs damping using a weight or material on the top of the chassis.
And SS components with large torroidal transformers can suffer from vibration.