I recently upgraded from Arya Stealth to HE1000se. I hear HEK Stealth is similar to Arya Stealth so my opinion might help a little.Would love to know how much slammy bass HE1000se has in comparison to HE1000 Stealth, how it slaps when It calls
Arya Stealth has more bass presence and generic punch. HE1000se can do the same punch and maybe even more but only if music calls for it. Otherwise it's very nuanced and track dependent. More of a shapeshifter.
HE1000se bass has more range to it. Arya bass is more simple, blunt but it's more, it's thicker and generally punchier and have more physical rumble down low. Arya Stealth is a lot more intimate sounding headphone so naturally bass comes out more forward. HE1000se lot more spacious and separated sounding headphone. So it's presentation gives you more field of view and intelligibility, insight in to music. Arya Stealth is more intimate, bolder and energetic.
People say HEK Stealth follows the footsteps of Arya Stealth revision. So i assume it's more bold in the bass than HE1000se and it's more energetic, aggressive headphone in the Hifiman eggshape realm. I would love to hear one and compare.