Many slow Blues songs are written in twelve eight time (+). This means there are twelve eighthnote beats in each measure. A measure of eighth notes in twelve eight time sounds the same as a measure of triplets in four four time. Although there are twelve individual beats which can be counted, twelve eight time is usually still counted in four as demonstrated in the following example.
One of the main reasons for using the twelve eight time signature instead of * is that it becomes easier to count when the eighth notes are subdivided. Since there is a number on each eighth note, 16th notes can be counted as + (and) as demonstrated in the following example. These 16th notes may be played straight or swung. On the recording, they are played straight the first time through and swung the second time through.