High current amp search

Hello, so as the title says, I'm looking for a 200+ wats amp (8ohm) that will double it's power down to 2 ohms but importantly also check all the audiophile boxes so strong, articulate, fast bass, smooth resolving mid-range and extended non fatiguing highs. It's proving to be rather difficult because hardly any manufacturers list  output into 2ohms. Budget is around 4000$ so I'm looking at mostly used. Besides something like the Krell FPB 300/400 CX which can be had for that much , what else can be recommended?