" … I’ve read that this is bad… " You have not heard it Yourself? Well keep it like it is.
A simple test could show You the physics behind Your question. Put a glas of water on a table and knock on the table. The heavier You knock the more ripples You can see in the water.
In the end it depends on the volume, frequency, Your favourite music style, the speakers, the shelf material (to transport the vibration), the isolation in the turntable (most have some) and the sensitivity of Your pickup.
Anyway best practice: do not allow the the vibration short circuit over the same fixture.
" … I’ve read that this is bad… " You have not heard it Yourself? Well keep it like it is.
A simple test could show You the physics behind Your question. Put a glas of water on a table and knock on the table. The heavier You knock the more ripples You can see in the water.
In the end it depends on the volume, frequency, Your favourite music style, the speakers, the shelf material (to transport the vibration), the isolation in the turntable (most have some) and the sensitivity of Your pickup.
Anyway best practice: do not allow the the vibration short circuit over the same fixture.