If you feel that a second pre is necessary (remember, the EMM has an active pre stage), then most probably an ultra clear device is indicated. Of the few I know, FM acoustics and Goldmund come to mind. Aesthetix is well regarded -- but I haven't heard the hot-rodded ones (the standard version is very good).
Mind you, these items are expensive! I'm not quite sure why you need a separate active pre... can you elaborate?
Mind you, these items are expensive! I'm not quite sure why you need a separate active pre... can you elaborate?