Still not quite there
It's hard when I can't post links!
Think of the sub bass lines like you might find in a dubstep or drum and bass track. Big bombs of sub bass. Again, Chernobyl is the best example. Listen to that for a moment. Imagine a collaboration between a modern classical and dubstep producer, if you will.
The two you suggested, the first one is beautiful (added to my playlists) but the sub bass in it is more just an added frequency of the main pads. The Biosphere track is closer, but it is kind of more extreme in the other way, as it is almost just sub bass! arctic ambient is a little too closer to non-music for what I'm after, as enjoyable as it is.