My band has the Bose F1 top/sub system and on occasion we seem to be stressing the subs. The grills are rattling and to the ear the woofers sound stressed, but there also is not a whole lot of impact on the dance floor.
At the same time, there is no indication of limiting or clipping from the speaker. My thought (and hope) would be that the built in limiter should kick in and/or we should see a clip indication before there was the potential for damage to the speaker. I guess it's possible that the limit and clip LEDs are not functioning correctly, but it'd be unlikely to have that issue with both subs, right?
The subs sound 'normal' at moderate volumes so I don't think the drivers are damaged at all. It's just at high levels that we're experiencing this issue. In some cases we are likely asking a bit too much out of the system (bigger system is needed) but I'd like to determine what's going on - or not - with the limit and clip indicators.