I know this thread is almost a year old, but I find myself in the boat as you were. I'm, from Mumbai, India and own a pair of Opus 2-2. Lovely speakers, till I blew my amp. When the amp came back from repairs, the speakers just didn't sound the same. So I changed my pre-amp thinking maybe I had damaged that as well, still no luck.
After reading online, I removed the connection plates at the speaker terminals and wired each component separately. The mids and woofers produce sound but the tweeters are deathly silent. I'm wondering whether its the tweeters that are busted or if the crossovers are damaged.
I'd like to know what happened with your issue and whether you were able to repair the tweeters. Please share your story.
Thanks in advance,