On the used market I think it's the $2500 cary 300-SEI. You need high efficiency speakers but it has that Western Electric 300B magic. I have one and consider it a 'keeper'.
Next up is a used ARC CA-50. Originally $4000, but now only 1600-1700 for a nice one. You get arc quality, support and sensible design at a bargain basement price.
For new, I think the $6000 full bore BAT 300x SE is the way to go. Many people like the $6000 rowland concentra II, but I love the BAT sound. Danananana....
In thruth though, when you get into the $6000 retail level for new equipment, I think you are better off buying something like a used placette with an ARC vt-100m2. You can put that together for 3500 and have a world class system.
