@OP
“only rate power over 4 Ohms (why on earth ???) at 170W. to compare apples with apples what would that rate on 8 Ohms ? 85 ? 100 ? In any case being high current it should be able to drive my Special Forty, shouldn’t it ? Any advice here ?”
I had the 2170 and it was GREAT with several speakers. Ran out of gas on some Dynaudio Contour 20s. Ymmv.
“only rate power over 4 Ohms (why on earth ???) at 170W. to compare apples with apples what would that rate on 8 Ohms ? 85 ? 100 ? In any case being high current it should be able to drive my Special Forty, shouldn’t it ? Any advice here ?”
I had the 2170 and it was GREAT with several speakers. Ran out of gas on some Dynaudio Contour 20s. Ymmv.