The tonality of the Eikon places it closer to the Teak than it does to the MDR-Z1R, IMO. Thus, I'd say that the Eikon is a natural upgrade over the Teak in technical terms such as resolution and dynamics. However, the bass on the E-MU is still very difficult to displace, even at the $1,000 mark. Hence, I wouldn't exchange the MDR-Z1R for an Eikon, especially if you already have the Teak; you would be having 2 headphones within your collection that sound more similar than the converse.I enjoy EDM and Hip Hop music especially on my Z1R, but the EMU Teak does just as well, both driven by a FiiO K5Pro. Would you exchange a MDR-Z1R for the Eikon?
I've seen other Z1R owners go down this path but came right back - Will I be one of them?
Moreover, the MDR-Z1R remains one of the supreme flagships for bass. There's a good reason why many owners love this headphone to bits - amongst other aspects, its bass presentation is simply one of the best around. I listen to a lot of EDM myself, and few headphones come close to the Sony in overall grandeur.