What this means for learners
MOGHOL and Javanese share 19 sounds — roughly 58% of Javanese's inventory overlaps with MOGHOL. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 14 sounds found only in Javanese represent the greatest pronunciation challenge for MOGHOL speakers. The adult brain tends to map unfamiliar sounds onto the closest native equivalent — a process that produces the characteristic "accent" of a second-language speaker. Learning to hear and produce these sounds as distinct requires focused ear training, not just repetition.
Conversely, MOGHOL has 10 sounds not used in Javanese. Native Javanese speakers learning MOGHOL will face the mirror-image challenge with these sounds.
Phoneme inventories from PHOIBLE. Data reflects one documented inventory per language; some variation exists across dialects and sources.