have you tried coincident triumph signature Extreme? It's 94db on 8ohm, it's tube friendly but since it's bookshelf, it's lowest bass note is 45Hz. A used is rare so you need to be patient.
If you want 91db and under 40Hz and under $2K, it'll be home theatre speakers like monitor audio models like RS6 and GR20. These speakers are sonically compromised compared to coincident.
If you want 91db and under 40Hz and under $2K, it'll be home theatre speakers like monitor audio models like RS6 and GR20. These speakers are sonically compromised compared to coincident.