Although shamans use singing as well as drumming and sometimes other instruments, a shamanic ritual is not a musical performance in the normal sense, and the music is directed more to spirits than to an audience.
Several things follow from this. First, a shamanic ritual performance is, above all, a series of actions and not a series of musical sounds.
Second, the shaman's attention is directed inwards towards her or his visualisation of the spirit world and communication with the spirits, and not outwards to any listeners who might be present.
Third, it is important for the success of the ritual that it be given its own clearly defined context that is quite different from any kind of entertainment.
Fourth, any theatrical elements that are added to impress an audience are of a type to make the contact with the spirits seem more real and not to suggest the performer's musical virtuosity. From a musical perspective shamanic ritual performances have the distinctive feature of discontinuity. Breaks may happen because a spirit is proving difficult to communicate with, or the shaman needs to call a different spirit. Typically, phases of the performance are broken off abruptly, perhaps to be restarted after a gap, perhaps not. The rhythmic dimension of the music of shamans' rituals has been connected to the idea of both incorporating the rhythms of nature and magically re-articulating them.