Since 1994, Tammy Brennan has been performing as a singer and composer of Western and Eastern classical, jazz, experimental electro-acoustic, electronic, dance and folk music.

Brennan began her career residing in Brisbane as an opera singer, later moving to Sydney and forming the electro-acoustic performance company ‘Pavo Cristatus’. In 1999 Australian Designer of the Year Akira Isogawa invited Pavo Cristatus to compose and perform the music for his celebrated fashion shows. While in Sydney, Brennan featured as a vocalist/lyricist on the album ‘Skin’ written by (Sony) artist Endorphin. Brennan is most well known for her vocal appearance on ‘Anguish’ which featured on the Australian film ‘Looking for Alibrandi’.