I just found out about a very nice review of the Leben CS660P Power Amplifier by Mr. Wojciech Pacuła of High Fidelity (Poland), which has also been translated into English at 6Moons. For those who may not know, the CS660P is available with two circuit variations, one of which produces more bass quantity than the other. My version is the version that has less bass, and given Mr. Pacula's comments I suspect he may have written about the version that produces more bass, but I really don't know for sure. Apparently it is very easy to convert back and forth between the two versions, but I forget the exact details. Below is a stock photo of the CS660P from the Leben web site. I love this amplifier!