I'm not sure if the internal amp on the Titanium HD is powerful (like the Essence STX which has an amp similar to the E9). In any case, the Sennheisers shouldn't have a problem with it. The Beyers MIGHT. I can't say, as I know very little about soundcards. Try the Nameless PC gaming thread, to see if your soundcard is powerful enough for something like the 250ohm Beyers.
I hear the HD558 has more bass than the HD598, so that may be better suited.
No. Any decent headphone will be fine vs other decent headphones. Just that it might be harder to focus on minute details with bassy cans over the ones that aren't as bassy. The DT990 Pros will still pick up the same sounds, just that the bass may/may not distract you.
You're overthinking it. The DT990s are well rounded for all purposes. I'd be more concerned about the soundcard possibly not having enough power to make the DT990s sing. Also, I found the 990 Pros WAY too bassy for my taste. This seems to be a problem only I have, and everyone else who has used them here has been fine with them. I'm sensitive to certain ranges in the mid bass, which is why it's probably worse for me than it may be for you.
I'll look into Titanium HD's amp. I really hope it's enough.
And well, it seems your competitiveness is the same as mine. That makes things easier.
From what you said, the DT990 would be a no-brainer then. Would be just as good as other more competitive cans with just a little more bass. That's exactly what I was looking for in a headphone. I'll just see to the card's power.
Since being distracted is very very subjective, it'll be a hit or miss. I'll just find out when I try those. Though since it'll be my first good headphone, I can very well adapt to them, can't I? Minimizing this issue. Also, if the bass doesn't overlap(forgot the term) other frequency ranges, that's fine to me.
And I can't say I am sensitive to certain ranges, because I have never had any good cans. So I can't say anything. But I like bass in music, for instance. Can't be sure what it'll be in games.
And yes, I overthink everything. Sorry for that.
But... in the end, from what you said, the DT990 may be my choice. I'll just look into some technical details to make sure.
Again, thank you very much. You were most helpful.
Edited by Carrek - 8/22/12 at 10:43pm