Well; now this is a quandry. The earliest SS gear had an easier presentation is my experience. Once you get past the early-seventies the SS designers went spec crazy and as a result they tend to sound harsh and gritty to my ears. I can't say for sure about the AU series but I personally avoid all that era when it comes to SS. Then around the late 80's/early 90's it seems people were becoming dis-satisfied with that sound and sales slipped so they turned completely around and all the SS stuff from that era sounds dull and lifeless. Go figure...