The analogue outs of this and the 2170 are not meant to use with a power amp. They are for subwoofer use, and so are feeded by a standard akm dac just for that function. I Iearned this the hard way, as I bought a power amp to complement the 2170, and it sounded just plain and bad, while the lyngdorf, by itself, sounded miles better. The nature of the technology used on these models would require you to perform your measurements on the speaker terminals side. I dont know If that is possible, but thats the only accurate and fair way.