I own and love the DJH. I haven't heard the MkII, but this is what Kevin at Upscale had to say about the differences:
Looking through your old forums, I see you own (or owned) the DJH. In my opinion, I honestly don't think the MkII will be an upgrade. You might want to call Kevin to get more info, but I encourage you to have a clear idea of what you're looking for and what you want to change in your system.
With the regular AE-3 and now AE-3 Mk 2 the bass can be a little bloated depending on the application, but the AE-3 DJHs front end topology is slightly different. It is direct-coupled, meaning there are no coupling caps between the input and output stages, which makes the preamp much more dynamic. I think it has incredible bass, great imaging, airy highs.His comments confirm what I heard with the standard AE-3.
Looking through your old forums, I see you own (or owned) the DJH. In my opinion, I honestly don't think the MkII will be an upgrade. You might want to call Kevin to get more info, but I encourage you to have a clear idea of what you're looking for and what you want to change in your system.