In　this　paper,　the　phase　space　reconstruction　of　audio　time　sequences　producing　by　different　instruments　is　discussed　based　on　the　nonlinear　dynamic　theory.　The　dense　ratio,　a　novel　quantitative　recurrence　parameter,　is　proposed　to　describe　the　difference　of　wind,　string　and　keyboard　instruments　in　the　phase　space　by　analyzing　the　recursive　property　of　every　instrument.　In　addition,　a　method　of　musical　instrument　family　classification　is　developed　using　several　classification　models　by　combining　the　dense　ratio　with　traditional　timbre　features.　The　experiments　indicate　that　the　accuracy　of　the　proposed　method　is　improved　by　4%-7%　and　3%　in　the　instrument　family　classification　and　individual　instrument　classification,　respectively.