How loud is an ARB compressor?

I think I'm going to have my ARB air compressor mounted on the passanger side cargo area wall. The bit of pointless indented space.

How loud is the compressor going to be? How long will it need to run before it has enough air to enage a front locker?

Mines where my spare was, its loud but its only on for 5 seconds to fill the tank and thats about it, Ive never sat in the back but I'd assume its pretty bad for the unlucky passangers. It takes 5 seconds or so to air up the tank then you can engage the locker(s) about 3 times before it needs to air up again.

Have you seen their new compressor? It's about half the size, and according to ARB, quieter too.