I've got an Esprit 2 but haven't tried clearing memories, but this is what the manual says (under the system level 2 heading):-
1. After switching the power on, enter the 'System Mode' from the initial screen (dot matrix screen shows 'System Mode').
2. Press the 'Down' key to enter the 'Memory Recall' screen (dot matrix shows '1-5 Step Recall ?').
3. Press 'Select' key to enter the 'Memory Reset' screen (dot matrix shows 'Memory Reset ?').
4. This will be entered by the reset of the +/- keys (I assume by pressing them together).
To the side of this is a note that reads 'Change the Model Memory beforehand which you want to reset', so this may just erase a single model memory rather than all of them.
Hope this is of some use.
