Rather than give a total number of hours, I recommend you play spkrs low volume in the beginning perhaps even using compressed music or music without aggressive transients & dynamics. Increase volume gradually. Also, give yr new spkrs a little time to "warm up" (i.e. the voice coils) before you play loud from cold. All of this shouldn't take more than a total ~30-50hrs altogether.
Break in period
What would the forum say about how long or how many hours of play time needs to occur before you can establish that your new loudspeakers are playing at optimum performance? I've heard opinions on this all over the scale!! Does this depend on the type and brand of loudspeaker, material of drivers, power being driven, etc? Can we agree on a nominal time period? I realize it may also depend on how loud you play them as well. Any thoughts? Many thanks.