Adjusted (dropped) the goop well this evening and listened to a bunch more LPs. Now the golf ball sits somewhere between 1/4 and 1/3 into the goop. Sounds more "open" now. Brass has more "splat"; drums have more "bite", and (the big test) piano sounds more like a a real piano - like a percussion instrument.
Two thoughts: 1) if I was to set up the turntable from scratch again, I would put marks on the golf ball so I would have a more precise measurement of how deep into the goop it sits, and 2) it's pretty cool how the turntable can be set up to sound different. For example, if you wanted a more "mellow" sound, you could damp the tone arm more by sinking it deeper into the goop.
In any case, I'm more and more impressed with the Amadeus every day. I have a fairly modest set up now, but I wanted to start with a good source. If, and when, I upgrade the back end, I'm sure there's even more in the grooves that I'm not hearing yet.
Personal side note: I'm particularly sensitive to how piano is reproduced. I took piano lessons as a kid so I have a keen sense of what a piano should sound like. One day, I was sitting in the living room of my piano teacher's house. In the attached dinning room, there were two grand pianos side by side. While I was waiting for my lesson to start, the piano teacher's long haired, hippy son and his friend where jamming and improvising on the two pianos - playing blues and stuff like that. As a kid, I had never heard anything like that. It was unbelievably fantastic - a life changing experience.