The most characteristic detail of a Mode 2 piece is the clef at the beginning of the piece. Shaped like an old fashioned telephone receiver, it is the FA clef, and is used almost exclusively for this Mode. The reason? Mode 2 pieces have a very narrow range; the reciting note is FA and the home tone, RE. On a normal staff with DO on the top line, these pieces would show up at the bottom of the staff,and lower notes could even be below the staff. The FA clef, located in the middle of the staff assures us that the majority of the piece will sit comfortably on the staff . Notice that there are a few notes above and below the key pitches of FA and RE, but for the most part, the piece circles around those principal pitches.
Listen for this, as you look at the piece.