I am sorry that happened to you- that can definitely damage ears and speakers. The speakers are less important.
I would recommend playing music with piano and vocals and listen to each speaker. You should be able to tell if it has any blown components. If the Gems are rear-channel speakers you may have to hook them up to the front channel. It should be obvious. Usually the tweeters go first, but not always. A blown woofer should be obvious. Stand in front of each speaker separately, and listen.
This maybe a higher power telling you to get a surround pre-amp better matched to your excellent speakers! Tell the wife the Marantz is dangerous. It's true!