It certainly is a spectacle because you haven't got a foot to stand on in this case.
Problem is you think you know, you may simply need to get off that pretentious high-horse and come down and take a closer look at what i am saying, oh no, maybe not, because your using a custom designed tube headphone amp, right? How can the FiiO E12 possibly match that... LOL.
Let me introduce you to a saying that you probably haven't heard before "He who thinks he knows, doesn't know as he ought to know" I have the proof right in front of me, (seek and ye shall find) and you simply have an empty pocket and a headphone that still isn't delivering the goods. Hate to burst your bubble, but all the 'pretentious' headphone claims you spout about well regarded headphones are just hot-air, plain and simple. I have the Holy grail and you don't, simple as that. So grab yourself a FiiO E12 and start searching through all the sub $100 headphones out there and eventually you'll find it, but who knows, your're an audiophile right, you may just be unappeasable? But my local audiophile who breaths eats and ****s and sleeps headphones hasn't got a clue has he, even though he has all the TOTL Sennheiser and Grado and Beyerdynamic headphones on show for audition and every other esoteric brand you can think of; actually, try some KRK headphones, their reasonably cheap and i can tell you PRETTY DAMN GOOD, but not quite as good as mine, but still damn good, in the interest of goodwill i can share that much with you. But nah you say, my ears are just a lump or artificial plasticine clued on the side of my head aren't they, even though i'm a mastering engineer and a music producer.
Every other headphone i have used to mix and produce music on, never gets the mix sounding right, the mix always has to me adjusted to conform to my Mackie HR824 mkII monitor speakers to get it sounding right, but after my hearing contest against the Abyss headphone i just confirmed what my ears heard, the mix comes out sounding perfect on the Mackie monitors after mixing it on my sub $100 headphone, no small feat i assure you, confirmation plus... yibidy yibida, that's all folks.