I had the HR Shearwater for a brief period and I could not get them to sound right in my room. What you describe is similar to what I heard, but there was also a glare in the upper midrange that was present all the time. This didn't change no matter where they were positioned in the room. And I was driving them with tubes as well. I passed them on in short order and have never been so happy to see a speaker depart my listening room.
Oz
Oz