I'd guess a dual TS-ish derivative closer to the voicing of the Nobels OD. Based on the description and knowing that Brett Mason is known to use it in the studio (he's one of the reasons everyone in Nashville uses it in the studio). That's where I would start. I also would bet it's closely related to the Paisley.
Without a gutshot, though, it's pure speculation. Which is sometimes just as much fun.

Edit: the Jet City demo has a gut shot.
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LED clipping in the feedback loop of a 4558.