I would guess that a 7 year old Avalon that has not been abused should be fine for a long, long, time. Some foam surrounds on woofers had a short life, but, that was discovered a while back so your speakers should be safe.
I know a lot of people running 60 year old drivers in systems that would completely shock those who think technology has advanced the state of the art.
I know a lot of people running 60 year old drivers in systems that would completely shock those who think technology has advanced the state of the art.