Few philosophical ideas are more thoroughly misunderstood than the Chinese concept of yin and yang. This isn't just a matter of opposites, or male vs female, though that might seem to be the case here, or dark vs light. It's about mutuality and interdependence, precisely the qualities that define improvised music. In this exquisitely recorded duo performance, pianist Rita Marcotulli, who once released a record called On the Edge of a Perfect Moment, finds herself on the cusp of another, this time in association with percussionist and vocalist Israel Varela. The music they make together is a seamless blend of jazz, world musics and effortless, unstrained abstraction. It's music of great clarity and richness, that confidently explores the opposition of light and shade, formal melody and acoustic freedom, and if there is a gender dimension to Yin and Yang, it lies in the ability of both players to combine "masculine" strength and directness with "feminine" delicacy and subtlety. Ultimately, though, it is music beyond category and so seamless as to defy any such distinctions. Yin and yang, joined together as qi, the material energy that makes the world go round