I got the Behringer Alpha and the Behringer Omega in the same order and I've gave them away to a portuguese Child Support Institution some months after buying and giving them too many "just one more chance"'s.
They should not be sold either as Studio headphones or even under Hi-Fi category.
Imagine making scrambled eggs with kick drum, toms, double bass/electric bass or synth sound.
The kick drum is overly boosted and the bass and low-mid sounds are veiled and conflict with each other to the point one cannot perceive a well mixed bass or synth line.
The mids and high frequencies do not sound clear at all.
Despite being open-back the instruments positioning is very constrained and limited to 3 different positions, far-left, centre and far-right. It's impossible to discern any different positioning in the stereo-field with these.
I find these headphones are not suited even for a so called "very relaxed" music appreciation.
They have very positive points though... Their amazing comfort and the removable cable with connectors for each speaker. I really liked them in these aspects.
For Mixing, Mastering or music appreciation... Please, go around.
You will be better served with semi-open Superlux or Samson for low budget, Sennheiser HD560S or AKG K702 for mid budget and for higher budget the Sennheiser HD600 or AKG K712 Pro.