What is a straight 8 in music?
Straight eighths is a specific performance practice in music. The term refers to eighth notes, so called from the manner in which they divide a measure of common time—into eight equal parts. In most common practice, eighth notes divide the beat of common time consistently and equally. In the early twentieth-century, jazz musicians began to alter the way they performed eighth notes in some of the music they played. These jazz musicians created a new style that incorporated uneven eighth notes. These uneven eighth notes began to divide the beat not in half but into two-thirds and one-third. As the new style became codified the uneven eighth notes began to be called swing eighths. This new practice roughly coincided with what is now known as the Swing Era in American music.
A straight 8 in music refers to a subdivision of notes that parts from the quarter note. When divided, quarter notes will become eighth notes. The role of eighth notes in music is to divide musical beats evenly in half. The reason why they are referred to as "straight" is because the division of the beat is clean and even. Most music is asked to be played in a straight 8 style.
In classical music, eighth notes are exactly one half as long as quarter notes. However, the prefer usage for eighth notes is for Jazz music, whose one-and-two rythm creates the unique atmosphere for which traditional Jazz is known today. Musicians refer to specific straight 8 notes as "shuffle" or "swing" eighth notes depending on the style that they play.