I have a Roland HD-3, with a beaterless pedal, supposedly the quietest pedal
around. But it still thumps because it hits the floor.
This matters because I have downstairs neighbors.
When I moved in I remodelled the floor, and added 3 layers of sound insulation
under the laminate floor.
I put the drum kit in the living room, as far from the bedrooms as possible.
I also only played during reasonable hours.
My neighbors never complained, but I solicited their feedback,
and they were more than willing to let me know it annoyed them.
LIke others said, only the kick pedal was a problem.
So I started with an exercise mat riser, underneath a layer of rubber and MDF board.
It was better, but the downstairs neighbors could still hear it in the living room,
which interfered with their TV time, but not in their bedrooms.
Then I added two more layers, using the same decoupling strategy that
the tennis ball risers use, alternating thick MDF layers with tennis balls,
but I used appliance vibration isolating feet instead of tennis balls cuz I
wanted less work (no cutting holes in boards for me).
All this paid off, while I never got to where they couldn't hear me at all,
they said they are ok with it now, it is no longer loud enough to be annoying
in any way.
The tennis ball noise isolation platform design is tried and true,
there is a great thread at vdrums.com on it.
The main point, is that while e-drums are a lot quieter than a-kits,
it can still be a journey to get to where the neighbors are happy.