@vair68robert A lot of vinyl sounds really good with the Thiels, and I do listen to mostly "classic rock". I have two turntables in my main system, a Sota Sapphire and a Technics SL 1200 MK2. The same record that sounds bright on the Sapphire will sound "good" (not bright) on the SL 1200, but loses a lot of detail, imaging, etc.
I'm using the same phono stage for both, but have a MM cart on the SL 1200 MK2.
It's quite possible it's not the speakers, it could be the cartridge, that the cartridge isn't set up right, the tonearm or cable, or how my phono stage handles MC vs MM cartridges.
The thing is, I have a number of other speakers that sound great in that system with the same electronics, so it feels like I'm trying to fit a square peg in a round hole.