Multilingual Semantic Retrieval for Apple Music Search

Apple ML Research · 2 days ago

Apple Music developed a multilingual semantic retrieval system using a 305M-parameter Siamese bi-encoder model fine-tuned from GTE-multilingual-base to improve search across 150+ storefronts and dozens of languages. In an online A/B test, the system achieved a 2.28% relative conversion-rate lift overall, an 86% reduction in the no-result rate, and a 7.93% relative CR lift for tail queries. The hybrid retrieval architecture integrates dense nearest-neighbor results with token-based indexing, enabling improved recall on misspelled, transliterated, and cross-lingual queries without retraining downstream rankers.