This work extends the familiar "query by humming" music retrieval framework into the polyphonic realm. As humming in multiple voices is quite difficult, the task is more accurately described as "query by audio example", onto a collection of scores. To our knowledge, we (the OMRAS research team) are the first to use polyphonic audio queries to retrieve from polyphonic symbolic collections. Furthermore, the technique we adopt can also be used to retrieve an entire set of real-world composed variations on a piece, also in the symbolic format. The harmonic modelling approach which forms the basis of this work is a new and valuable technique which has both wide applicability and future potential.