# Welcome to the Highcharts Gantt JS (gantt) Options Reference

These pages outline the chart configuration options, and the methods and properties of Highcharts objects.

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# series.gantt.sonification.defaultInstrumentOptions.activeWhen.crossingDown

Track is only active when `prop` was above, and is now at or below this value.

If both `crossingUp` and `crossingDown` are defined, the track is active if either condition is met.