It was differentiated from the typical tin pan alley popular music of the times by dark tonal qualities which were the result of mixing major, minor and7 th chords with the music.

• 后来在融合了大小调和七和弦以后，12小节布鲁斯就以其低沉忧郁的音质从典型的流行音乐时代脱颖而出。