@reg19 The 6SE was somewhat mechanical sounding - hard in the mids. The Backert is smooth! with a huge soundstage. Remarkable detail without getting in your face. Rich, large, detailed, smooth, emotional. It just sounds like music...
That is with the RCA 12SN7 tubes which is what was recommended and supplied by the reseller I bought it from (Dr. Vinyl - Jose Ramirez - in MD). I have the stock tubes (Genelex 12AU7) but have not used them.
I think the gain is a bit higher with the 12SN7 tubes and balanced output, but I don't know the values. But still less than the 6SE and much less than the Cary 05.