@@tomaskroupakkfoto4132 It mainly depends on the performance of loudspeaker involving its outstanding sound level at the lower end, usually experiencing no problem with large diameter of woofer(12'')as well as high sensitivity(≥90dB/W). Having considered the official claimed sensitivity of your AP(89dB/4Ω=86dB/1W/8Ω),an amplier of at least 100W/8Ω with bass compensation control is better coupled, and unlikely being matched with those SET tube amp under 10 Watts.