I can understand you well.
I have owned a pair of Cornwall IV for 5 months now and have the same problems. Previously I had two RF83s playing on the same chain, but unfortunately I sold them. To the Cornwalls:
The bass is extremely thin. In order to get a sound similar to that of the RF83, it is necessary to increase the bass by more than 6db (on the AVR) after 5 months to get a bearable bass. But the tweeter also lacks a lot. The briliance is missing. Yes, breaking-in did help a bit, but I'm not satisfied. And I'm tired of hearing that I should move the speakers around the room, change cables and change the amp. It's all bullshit and worked great with the RF83.
My Souround rears (RP-160M) sound more coherent.
Unfortunately, I can't give them back
I wish you good luck, but I can't give you hope.
If I find someone, I will sell them and get something else. It will probably not get any worse.
(I translated online with Deepl)
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