ElKayDbl v1. 0: Learn Korean Double v1. 0: Finish up Basic Korean Alphabet: Next Level Version of ElKaySng. 1. Basic Korean Lesson for foreigners. I) Single Consonant(monophthong) and Double vowel(Diphthong). First sound: 14 ( consonant characters including silent 1). Second sound: 11 characters(Diphthong: Double vowel).