I only listened to the TH900 for 10' or so so take whatever I'm saying with a pinch of salt. Anyway, to me the there's a vast difference between the Parterre and TH900 across the whole spectrum. The TH900 is no doubt thinner and colder sounding than the Parterre, there's less emphasis on the midrange compared to the way the Parterre renders the mids. The TH900 also possesses more energy in the upper spectrum, as well as details and extension. However that would make the TH900 less intimate and musical. Bass on the Parterre is fuller, with a tad more focus on quantity while with the TH900 there's better sense of space when you listen to the lower end. I'm not entirely sure which one has more bass since the TH900 was plugged into an amp at that time, but all in all the TH900 is more suitable for instrumental/classical while the Parterre will do better with vocal related genres.
Thank you for your impressions. I'm a bit worried about the mids though. You described them before as not really forward and not really recessed. I'm not sure if that would be my sweet spot with vocals since we do hear things a bit differently I bet. That was the problem I had with the TH900s.
I hear the Parterre would be closer to the Kaedes/TH900s than the 334 would, and not sure if it's something I'd want.
I believe most of my music would benefit more from an exaggerated mid section instead of something more naturally sounding (could be wrong, but that's what I've concluded for now).