There is no clear-cut definition of tribal house music, instead tracks are usually classified or perceived as tribal because of their live sound. Tribal house is reminiscent of the ethnic music of various tribes of Africa and South America, and it is not unusual for this music to feature chanting and ululation as a cappellas. Tribal music can be produced with either live (i.e. with real drums and instruments) or digital instrumentation: however, live-produced music of this sort in the purest sense is seen as ethnic, while digital tribal music is called 'tribal house'.