Organ music can be pretty demanding, but it seems something’s amiss. I’m running a pair of KT66s in triode that produce in the 10-12 watt range, and am able to power 89db sensitivity speakers fairly loud in a large space, Granted I haven't fed them low pedal notes lately. Tubes typically break up pretty gracefully without causing damage. I do have an active subwoofer to augment the bottom octaves, but the mains still run full range without issue. What model is your amp?
How does a speaker blow out?
I don't understand how a speaker "blows" if the wattage of the amplifier is less than the upper limit of the speaker's limit. Then again, I guess I don't really understand what "clipping" is. The amp is 22w, I was listening at a moderately high level, there was a bass heavy section in the music, and then I heard the most painful noise coming from one the of woofers. Sad.