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

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

Feel free to search this API through the search bar or the navigation tree in the sidebar.

# plotOptions.xrange.sonification.defaultSpeechOptions.preferredVoice

Name of the voice synthesis to prefer for speech tracks.

If not available, falls back to the default voice for the selected language.

Different platforms provide different voices for web speech synthesis.