Interesting to see an owner of the HE-1 posting here. I would add to balance the opinions on the 009s capabilities, the jump from being driven by the 007T or my last Stax amp, the SRM-717 to my next amp the KGSShv was huge, another headphone completely. Everything got bigger, wider, smoother, deeper, more 3D. Referring to bass in particular, no contest really, the 009 goes deeper and faster on KG amps.
Later when I got the KGSShv Carbon, it scaled up again with even more textured bass and a massive soundstage. Treble extension went up as well without any harshness or edges creeping in and layering shot up again. So I am wondering what the gap would finally be with a well driven 009 v the HE-1? Maybe just flavours? I will get my ears around the HE-1 for a quick demo in 2 weeks at Can-Jam so may get an 'idea' though not ideal conditions or what I would call a full demo TBH.
Congrats on your HE-1, no taking away from it, it has to be the ultimate 'off the shelf' HP system.
Keep the feedback coming Raypin!