How Do You Spell ON UP UP?
Pronunciation: [ˌɒn ˌʌp ˈʌp] (IPA) 
The spelling of the phrase "on up up" might seem confusing at first glance, but it becomes clearer when broken down phonetically. The first syllable, "on," is pronounced with a short "ah" sound, like "ahn." The next two syllables, "up up," are pronounced with a long "uh" sound, like "uhp-uhp." This spelling choice emphasizes the ascending motion implied by the phrase, as if something is moving "on up up" to a higher level.
