String band

The string band originated as a subgenre of old-time music. It spotlights a group of acoustic string instruments, sometimes even to the exclusion of vocals.

During the 19th and early 20th centuries, other stringed instruments began to be added to the fiddle-banjo duo that was essential to dance music of the early 19th century United States. These other instruments included the guitar, mandolin, and double bass (or washtub bass), which provided chordal and bass line accompaniment (or occasionally melody also). Such an assemblage, of whatever instrumentation, became known simply as a "string band."

In the 1870s Negro dance houses of Cincinnati had musicians who played violin, banjo, and bass fiddle.[1]

East of the Mississippi, the genre gave way to country music in the 1930s and bluegrass music in the 1940s. During the same period, west of the Mississippi, Western musicians retained the acoustic style of the bands while the big Western dance bands amplified their strings.

Source : http://en.wikipedia.org/wiki/String_band