Utilizing Korg's "Multi Modelling Technology" (MMT) based on the RADIAS and R3 synths, the XL is equipped with 128 malleable sound programs for full user customization. Seven waveform types provide access to formant, noise, and PCM/DWGS data for realistic analog modelling, with advanced capabilities such as cross-modulation, unison stacking, and variable phase modulation enabling limitless editing possibilities. In addition to Sync and Ring modulation types, the unit is pre-loaded with 17 effects that range from chorus and reverb to MIDI-clockable delays and grain shifting. Similar to the other micro models, the XL features an integrated 16-band vocoder with dedicated controls including "Formant Hold" for continuous tonal alterations.