My mandolin teacher recommends Transcribe .

It looked very interesting on his computer; I haven't bought it yet to give it a full workout. This is the feature that I find most interesting:

The "spectrum" feature displays the strength of the various pitches in any chord or note you select, in the form of a graph - a wavy line over a piano keyboard graphic. The height of the various peaks in the graph indicate the strength of the note above which the peak appears.