Focker
Headphoneus Supremus
Its actually good to hear that the 400i might not be such an "obvious" upgrade - they really priced me out anyway, and I was sure the single-sided planar was going to be ultimately a little less "fun" in the bass department.
Considering I've got the HE-400 sounding about as good as I can, I am going to focus on getting probably something with a Harmon Curve next - like the NAD HP50s or something else. At least so far it seems possible to get them for $300 or less. Frankly, I'd rather be in a $200 can at this point as my next big purchases will all be home theater related . . .
Just my own opinion, but yeah, I think the HE-400i is a step backward sonically. It's just lifeless, whereas the 400 truly captivated me from the first listen. I'm really regretting my decision. I really figured this would be an upgrade.