What is the basic premise of the source-filter system of vowel production?

The source-filter system of vowel production is a widely acknowledged explanation of how the oral cavity shapes speech sounds. The general premise of this theory is that the voicing source is generated by the vocal folds and then routed through the filter of the vocal tract, where it is shaped into the sounds of speech. Changes in the shapes and configuration of articulars such as the tongue, mandible, and soft palate control the resonance characteristic of the vocal tract, and the resonances of the tract determine the sound of a given vowel.