Eleven can be controlled directly from any compatible Pro Tools worksurface. Eleven appears along with other plug-ins and can be assigned, edited, bypassed and automated using the Insert section as available on the particular worksurface being used.
Some amps that have relatively few controls (such as the Tweed Lux) will display controls on a worksurface that are not actually available with that particular amp model. Even though you can adjust these unused encoders or switches, only those controls seen on-screen for any amp can be adjusted from a worksurface. Changing an unused control does nothing to the current amp, but does alter the value of that unused control. If you switch to a different amp that does include that (previously unused) control, the new amp inherits the altered setting which can lead to sudden jumps in gain or other settings.