Quote Originally Posted by 02audionoob
It is very common and even consistent that the Marantz gear from the 70's produces more power than its rating. The receiver is designed to run two pairs of speakers. Why wouldn't it run one pair of 4 or 6 Ohm speakers?
It's all about stress. While your right that back in the 70's Marantz gear was underrated power wise (to get better THD readings) do you really want to stress this vintage piece with a difficult to drive speaker? Filter caps, and power transformers do age. After 30+ years you cannot expect them to stand up ad perform to the same kind of specs as new. That these units still can PLAY is a testament to their great build quality, why abuse them now in their golden years? Especially when good high efficiency/high resistance speakers are available.