BEAT (situation), as in lame, boring, stupid, not fun, sucks
BEAT (person), as in whore, slut, undesirable company, someone who continually sucks at life in general, etc.
BEAT (place), as in overcrowded bars/clubs, places where undesirables hang out/solicit, places that people have generally below average IQs, parties that suck where people are being obnoxious, fighting, yelling, or all of the above(s).
BEAT SCENE can denote either a person, place or situation. see below.
Greg: Man, today at work I had to deal with all of these trons. What a beat scene.
BEAT SCENE person:
Nico: I hate going out to stupid bars in south side, they're always full of beat scenes.
BEAT SCENE place:
Greg: Let's go to Primanti's to watch the game tonight.
Nico: Fuck that, it's such a beat scene