I tend to listen to concert DVDs at "realistic" listening levels. Using a Marantz SR-18 receiver I've blown the bass driver on a pair of Alon IVs. The cones just became seperated, so not really a blow-out. I've also rattled the cabinets loose on a pair of Klipsch KLF-30s. The 30s were known for having faulty cabinets, so I'm not sure these were my fault either. Some criticize others for listening to music at higher volumes. But, just as personal preferences vary between speakers (ex: some love Klipsch, other despise them) so do preferences for listening levels.