On a crowded train in a downtown subway tunnel, a chorus of spring birdsong sneaks through the thicket of thick winter coats, but if birds can imitate ringtones, I suppose the reverse makes sense, too.

A couple stops on the doors open to let in a flood of freeling, pealing banjo played well, and it drowns out the Blackberries and thumping bass notes; it sounds just like wood, gut, and skin and the natural world but as loud as it is there must be an amplifier plugged into a socket out there on the platform somewhere.