When used to address someone who is very angry, this phrase generally means "calm down" or "stop screeching" or "stop yelling." It notes that a person raises her voice in both tone and volume when she gets upset.
Sister: I can't believe you read my diary!
Brother: Whoa... Take it down an octave. It's not like I made copies of it for everyone at school. I only made copies for my friends!
Brother: Whoa... Take it down an octave. It's not like I made copies of it for everyone at school. I only made copies for my friends!
by MookieJam10 June 19, 2011
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