Mullardman
Moderately extreme...
I designed the E-IX to be a latter-day Kan with bigger balls. By most accounts, they seem to do the job. Here is a picture courtesy of Vuk. You can build a pair yourself by referring to this reference post, or as another poster suggested by contacting Stefan a.k.a. Orangeart.
Hoffman's Iron Law is a bitch. Hence, my E-IX offers about 50% more enclosed volume by virtue of a deeper box.
Which to me seems a good way to go, as it maintains a minimal sized front panel and the issues that can avoid.
Mull