The Neumann U87Ai is the current version of one of the most recorded vocal mics of all time. No doubt it costs a pretty penny but it just doesn't work well on vocals. The U87Ai is a fine instrument mic as well as will be illustrated in this video.

In this video Dan uses the U87 to brighten up the sound of his cheap nylon string acoustic. Plugged into the Focusrite ISA428 this is quite a channel to be recording a $40 guitar through, but who said a cheap guitar has to sound bad? It just needs a little help.