Intelligence level is hellier than treble peaking on speakers in the ghetto
He is referring to himself throughout this entire verse, including this line.
Hellified means extreme or a large amount of something, hellier is a derivative of this.
Also, since he uses the term “peaking” after treble, he means the treble is high.
He is implying that he has a high level of intelligence.
Sometimes people do turn their treble down and bass up but they don’t put tweeters in their cars for nothing.
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