I imagine a similar sort of sound might be the rigging slapping against aluminium masts. That's a sound that fills me with peace, because it makes me think of time out on the boats. That too is a lonely sound in a way, because it speaks of a boat not under sail. But I used to sneak away to the family's little boat on Turnchapel marina and spend the night snuggled up in my bunk. Listening to that sound as the water rocked my little hideaway gently is still one of my favourite memories of home.