True, but remember what’s quiet to a human may be quite different to what’s quiet to a hedgehog. When reading about these things it’s surprising how often things that we might not consider - like how vibrations travel though the ground - can confuse wildlife in ways that we might not expect when viewed through an anthropomorphic lens.

Yea, my neighbors battery powered mower is super quiet. I don't even know when they run it.

Mine is also electric and my wife says (i'm always too close to it) it's easily 4x as loud. Not sure what the difference is.