The place I bought the SE535s has the 846s so I'm almost definitely going out tomorrow to talk about a swap, LOL. It's a 2 hour drive, though. So I do want to make sure there's a good chance I'll be changing before I head out.
So the bass is standout, but not in the sense of being overly boosted? I suppose I'll be listening for myself, just sort of mentally preparing myself for this.
If I do say so myself, my vocabulary is anything but limited, however I am at a loss as to how I could go about explaining how the bass differs between the Shure SE846 and the mass marketed bass heavy headphones that are ready to audition at any JB Hi Fi store (replete with vanity mirrors installed on the walls! - rofl!). If I had not handed my IE8s to my mother this job might be a lot easier.
As I say, you are not just hearing music through these things; the experience is much more engaging than that. Bass, frankly, has a lot to do with this, for it is a major component in rhythm. If real dubstep is your thing (no, Skrillex is not dubstep - think Mala, Distance, Hatcha etc.) the 846 has the ability to plunge to some seriously abyssal sub-bass depths. No strange, other-worldly, fluorescent (if we could see them) creatures who somehow manage to exist in spite of receiving virtually no sunlight were harmed during this expedition. In other words, bass detail spans the sub, the mid and the upper without compromising detail that lies beyond.
Flicking through my collection it is very difficult to find a track that is light on bass. "The Ballad of John & Yoko" is the best I could find before losing my patience with iTunes and its shufflings. The bass guitar rings so true that it is a poignant reminder of the instrument's role in the "rhythm section". From memory the IE8s rendered this song a walk in stodgy mud.
I am not exactly succinctly answering your question here am I? Sorry, too many caipirinhas and rum old-fashioneds last night. I suppose what I am trying to point out is that there is nothing artificial nor boosted about the bass whatsoever. It is natural (to my ears at any rate - nigh on perfect) and with its impact and detail it is likely you won't listen to your music in the same way again.