Can 6x9 speakers get damaged if you have a sub?

If you have 6x9 speakers fitted in the rear parcel shelf and also have a subwoofer in your trunk, you are most likely to reduce the life span of the 6x9's.This is because of constant bass vibration from the subwoofer can vibrate the 6x9's voice coils and cause serve damage to them.Some 6x9 speakers can stand all the bass vibration and some can not.Most 6x9 speakers at high volumes bottom out, meaning the cone and magnet and hitting against each other because of the tremendous air pressure from the subs.So either get a low powered subwoofer below 50 watts rms, if you do want to reduce the chances of your 6x9 car speakers getting damaged from movement.