Thanks glad to be here.
What would you say are the main differences between the Beyer Dtx 710's and the Superlux Evo's?
I noticed the Dtx 710's are open back, is that like an open baffle sort of effect on bass or more like a port?
Well, I don't or haven't owned the Beyers before but I think you did well based on the short amount of research I just did looking them up.
I would say the build quality looks to be about equal.
It looks like the Beyers have a slightly exaggerated bass response which is okay in an open back design (which usually lacks bass compared to a closed back headphone). The Evos also have a slightly exaggerated bass response which I prefer personally actually.
The Beyers are "open" meaning that the back of the headphone is open to the environment. The driver is usually covered by some mesh or other housing but it a lot more open to the outside environment. When you're wearing an open headphone you can usually hear the things going on around you so it's best to sit in a more quiet room. Like you can hear what is going on around you, your music won't be a secret to anyone else either. All this is fine if you have a quiet room, as I use my open headphones in my office when all alone (I use some Sennheiser 558s).
A closed design is what I prefer for a mobile solution as well as when I'm laying up in bed next to my wife and I don't want to disturb her with my music. The driver and you ear are closed off from the environment. Although, a lot of closed designs do contain some small holes to let miniscule amounts of air into the driver or your ear. Closed headphones are usually not as known for having as good of a sound stage as open headphones, but are known to isolate the listener better. They are also capable of a better bass response due to the design and the amount of seal they have on your head. I really like my Denons and sometimes (like right now listening to some Daft Punk) I wear them in my office even though I could listen to my open Senns.
The Evos are a semi-open headphone meaning they have large port or air holes. They kind of isolate, have a decently large sound stage, and also have a pretty good bass response. They are IMHO a good compromise between the two styles. They were very inexpensive and if I didn't have my other headphones that cost about 3 to 4 times more a piece, I would be happy with those Evos. I do however, have my closed back Denons and my open back Senns that I just slightly (I really do mean just slightly. They were 85 -90 percent of my other headphones) prefered to the Evos so I sold them. Judging from what others have said about those Beyers though I think you will be happy with them. Make sure you tell us if you aren't happy (or if you are) but try and put a finger on what exactly you aren't happy with and some of these fine people will be able to steer you in the right direction.
Good luck and sorry about your wallet!