If it’s a Box Woofer Klipsch. You NEED JUICE to move that Woofer.
+1 @rajugsw - although the horn’s tweeter and midrange can easily handle flea watt amplification, the less than efficient (difficult impedance curves) woofers are tougher to control without adequate power
For “warm” non- tube amplification, maybe a GanFET like AGD and Atma-Sphere or a sliding bias amp like Krell.