Only in Akan 30
What this means for learners
Akan and Dioula share 30 sounds — roughly 50% of Dioula's inventory overlaps with Akan. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 9 sounds found only in Dioula represent the greatest pronunciation challenge for Akan 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, Akan has 30 sounds not used in Dioula. Native Dioula speakers learning Akan 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.