Reo- The 80 dB sensitivity is for 1 watt, but measured at 15' from the speaker. If you search the web you will see that translated to more common specification , it is considered to be about 93 dB sensitivity, which is well within the range that is considered "tube friendly". Depending on your listening distance and room size, you probably could drive that speaker to very high levels w a 300b based, 8-10wpc amp. It might run out of steam at very high volumes on orchestral music, but as Rrog says, 15-20 wpc should be able to reach ear bleed levels in a medium size room. Also, speaker-amp matching depends on a lot of different factors, sensitivity being only one. Also relevant are room size, type of music, typical volume levels, minimum and nominal impedance, how much impedance varies w frequency (so-called impedance curves), phase angle, etc. Do some searches on topics like speaker-amp matching and check out Atma-sphere Music's white papers to get a start on understanding this complex topic.