The Omegas have a sound signature all their own, or at least they are really directly comparable to other electrostics. The strengths are a way of taming digital
(or other) audible flaws that cause discomfort or pain while still retrieving detail. Thus, they are not ruthlessly revealing, just revealing. OTOH, there is definitely a kind of flat-panel personality (like with Martin-Logan speakers), a kind of shimmering, slightly hazy sound sometimes that let's you know it is a vibrating membrane driver, but just on some musical components on some recordings. That makes it sound worse than it is, because it is actually a kind of soft, romantic coloration.
It is actually kind of relaxing. There is still depth and soundstaging and very good separation of things, but things are a bit miniaturized. Bass is not overpowering, but not weak either, and it is very detailed. Vocals are very sweet and mesmerizing. Images are pure and fairly dense, but not super solid.
The AKG 701s are a different animal. They sound like an excellent dynamic speaker with great driver integration. Vocals and all midrange components are direct, pure, dense,
and have nice soft edges with no grain. At the same time they are not pushy. Upper mids/lower treble is not ringing or to "shiny," but still very liquid. In fact liquidity is the main sonic signature of the 701s, in contrast to the Senn 650s which can be a little dry and bit buzzy (but are warmer). But, with the wrong amplification (or when not broken in), a recording with tilted-up or pushy highs can
sound piercing and painful. This only happens occaisionally but it does happen. For some reason, the (first generation) Headroom Max amp sounds good with the 701s, especially with it's high-frequency cutoff filter switched on. The 701's bass, while not as warm as the Senn 650's, tight and ample when broken in. I did not feel like I wanted extra bass. The bass is not exaggerated, but is there when called for. Image separation, sizing, and localization in 3 dimensions is good and does not sound artificially pronounced or flattened. The soundstage is quite satisfying. Finally, comfort is really nice in my opinion. They are not over-clamped or hanging loose, and the velour pads feel great on my head. I think the 701s are a terrific bargain without question.
