MTS-ESP allows one central source instrument to retune all compatible plugins simultaneously in a session

MTS-ESP is a host-agnostic shared-memory protocol where one instrument instance acts as a source and broadcasts tuning data to all other MTS-ESP client instruments in the same session. In Surge XT, a single instance can be designated as the MTS-ESP source, loading SCL/KBM tuning or using the Tuning Editor; all other Surge XT instances (and compatible third-party instruments) then retune automatically. Only one source can exist at a time. Dynamic Microtuning (default) adjusts held notes immediately when tuning changes, enabling gradual tuning morphs. ‘Query tuning at note on only’ preserves held note pitches through tuning changes for a more traditional approach. If the source crashes without deregistering, Re-Initialize fixes the broken state.

Examples

Set one Surge XT instance as MTS-ESP source and load a 24-TET tuning. All other MTS-ESP instruments in the session will immediately retune without individual configuration.

Assessment

What is the difference between MTS-ESP Dynamic Microtuning and ‘Query tuning at note on only’? What must you do if the previous source instance crashed and left the session in a broken state?