Best Preamp round $8000

I would encourage you to check out my Art Audio Conductor.  I was using a PS Audio BHK with Tunsgram tubes prior to my Art Audio relationship and was pleasantly surprised at relative imaging.  I found the soundstage on the Art Audio to be quite a bit wider than the PS Audio.  I have my demo listed for $6750 while it is new for $8499.  Haven't put it up against the ARC Ref 6 but it is a darn nice unit.  

I have the Luxman CL38-U SE. I've had it for 2 years and it can compete w/anything in th 5-10K price range. Very conservative on tubes. As quiet as the day I bought it. Plus the phono is excellent. A3 tube design w/4 step up transformers. 2 for MC High and 2 for MC low. Has tone controls and a mono switch. Luxman has an excellent reputation building tube gear. 

Ayre KX-5, Aesthetix Calypso

@topfinadv  Are you looking for balanced or single-ended?

First Sound makes some nice units if you don't need balanced output(s)