What this means for learners
Malayalam and TULU share 28 sounds — roughly 53% of TULU's inventory overlaps with Malayalam. 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 TULU represent the greatest pronunciation challenge for Malayalam 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, Malayalam has 25 sounds not used in TULU. Native TULU speakers learning Malayalam 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.