A hollow sounding explosion, could be used for a metallic hit or slightly muted bang.
Old flashgun powder is lit as the shutter fires, providing a dark old-press 1920s feel.
Reversed recording of hitting the low piano keys. Dark horror scene or flashback building up to a particular moment before ...
Sample recorded with a Dolby 5.1 channel mic, old 1967 GPO 746 rotary phone ringing.