I bought one of these years back in kit form which was very affordable. The purpose was to bi-amp a speaker - - specifically, to use a tube amp for mids and highs with a solid state amp for the woofer. It was fun!
I bought these during the $40 Christmas eBay sale. It’s too bad they don’t have a sub out or something. Just no bass at all.
Mids and highs are nice though, better than any other computer speakers I’ve heard, which is what I wanted to use them for.
HifiMan 400i (open) and Monoprice m565c (closed) are great sounding planars.
I recommend putting any new headphone through tests right away so you can exchange if there are any issues. For planar especially, check for channel imbalance and buzzing bass.
The Monoprice m565c are very good. I tried the m1060c and they were just too uncomfortable and their sound was a bit off somehow. If you like the 400i, you’ll love these. Smoother treble, deeper bass, and they’re very efficient. I run them in the Atom at home for best sound, but my iPhone...