Adults are able to learn sound co-occurrences without conscious knowledge after brief exposures. But which dimensions of sounds are most salient in this process? Using an artificial phonology paradigm, we explored potential learnability differences involving consonant-, speaker-, and tone-vowel co-occurrences. Results revealed that participants, whose native language was not tonal, implicitly encoded consonant-vowel patterns with a high level of accuracy; were above chance for tone-vowel co-occurrences; and were at chance for speaker-vowel co-occurrences. This pattern of results is exactly what would be expected if both language-specific experience and innate biases to encode potentially contrastive linguistic dimensions affect the salience of different dimensions during implicit learning of sound patterns.