I've had 3 Swamp ash guitars and they've been the opposite of muddy, unfocused, loose. Must be more the particular piece of wood and construction more so than species because all 3 have been tight, focused, bright, and articulate.
Two of them I have here now: a swamp ash body maple cap Mayones. It's very tight, articulate, defined regardless of pickup. I've had a cold sweat, Painkiller, DD, and Iron Man in the bridge and its always very tight and defined and plenty bright and snappy.
I just got a Skervesen that's all Swamp ash loaded with a Lundgren Black Heavens and its super bright, snappy, very articulate, extremely tight.