HD 800 and HE1000 with the yggdrasil and ragnarok should be a great match?
My HE1K sounds great through the Yggdrasil / Ragnarock. The bass is so impactfull and textured. Likewise the mids are so sweet yet detailed and transparent. The highs are spot on perfect, do to the exquisite micro detail. The Ragnarock is a powerful beast of amp, that can make any headphone sing like a muse of old. One can not go wrong with a Yggdrasil/ Ragnarock.