I started out with NOS GE 5751's in my Cornet. I loved the mid and highs - just absolutely natural sounding and worked great with my AKSA pre- and amp. However, there was no bass - no low extension - nothin'. Could be a gain issue; could be a brand issue, but I swapped them out for Sovtek 12AX7LPS. They're not quite as smooth in the mids, but the bass is rock solid and rich.