1.it means pump up the volume.
2.for some adrenaline fueling phrase for the start of your day.
3.saying it just to confuse the fuck of outta some one in the process

also you can just say blast me up if you got no one to say it to. or if it's a female
1. A-YO i ain't hearing shit BLAST ME UP SON!!!!!!!!!!!!!!!!!!!
2. 3 minutes before my game........fuck it BLAST ME UP SON !!!!!!!!!!!!
3. boy: AY GIRL BLAST ME UP SON!!!!!!!!!!!!!!!!!!!!!!!!!. girl: What?
by mini paco April 3, 2010
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