Robert Siegel talks with Finnish vocalist Wimme Sari about his music, a form of traditional singing called "yoiking". The yoik is used by the Sami reindeer herders of northern Finland to evoke a feeling, or express a desire. A yoik is a chant of sorts; it can have real words, or just sounds, or a combination. Wimme, a musician who goes by his first name only, has developed the yoik into a fascinating modern form. The CD is Cugu by Wimme.