Unlike mainstream neural speech synthesizers, articulatory speech synthesizers directly simulate the process of speech production at the articulatory and aero-acoustic levels. This talk presents the articulatory synthesizer VocalTractLab 2.3, its main model components, and its multiple control levels. We also present recent improvements in the synthesis of German diphthongs, the modelling of energy losses in the vocal tract, and new applications of the synthesizer. The synthesizer is available for download at www.vocaltractlab.de.