What this means for learners
Madurese and Cham share 25 sounds — roughly 71% of Cham's inventory overlaps with Madurese. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 10 sounds found only in Cham represent the greatest pronunciation challenge for Madurese 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, Madurese has 10 sounds not used in Cham. Native Cham speakers learning Madurese 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.