I just tested 3 preamps: Grace 101, Daking Mic Pre One and a Universal Audio Solo 610 with my U87 and RE20. While I was hoping to test a Vintech & DW Fearn, I decided with other project irons in the fire I could not truly afford those pieces now. To tell you the truth, while I could hear differences between the Grace, Daking & UA, I could not quantify those differences in any practical, meaningful way, nor could I assess which one was better. I thought they all sounded pretty good. But after the testing I recorded a session with the Grace and the U87. The Grace sounded great, however, after editing the session I became disenchanted with the sound of it. I couldn't tell you why. Both the Daking and the UA seem to have a little more poop to them, but I didn't have the time to re-record the session twice to assess my extended reaction to them. So I guess my thought/question is: Do I have lousy ears or do you guys just have golden ears? I can hear good v bad better than a lot of people, but I don't have a clue what to do about it. ...and at my age can I improve my listening?