The ZEN is the problem. The treble is not sparkle. No clearer mids. And, importantly, everyone knows it is praised for its sound sig everywhere on the net but it cannot boast for the bass response, definitely it is not for the bass heads. With foams, the whole sound get muffled, spoiling the mids even further. Maybe it is a beauty with its siblings amp Runabout which I do not own nor did I have a chance to test it with.
Ah, I see. The Mojo is plenty powerful already & it should be able to drive the Zen. It also has a warm sound signature with nice slightly boosted bass so I'm surprised you still find the bass of the Zen to be lacking when paired with the Mojo. If the Mojo doesn't provide good synergy between it & the Zen, then I doubt the Runabout will.
I think the housing diameter is like common housing mx500 etc..
Not comfortable for me but not bad either..
Really? They do feel very slightly larger to me. It might just be my particular ear anatomy. Anyway, I'll try putting on different foams. Currently using the ones it came with.