{"id":21602,"date":"2025-05-22T18:24:59","date_gmt":"2025-05-22T14:24:59","guid":{"rendered":"https:\/\/krisp.ai\/blog\/?p=21602"},"modified":"2025-06-30T18:10:49","modified_gmt":"2025-06-30T14:10:49","slug":"introducing-accent-conversion-v3-5","status":"publish","type":"post","link":"https:\/\/krisp.ai\/blog\/introducing-accent-conversion-v3-5\/","title":{"rendered":"Introducing Accent Conversion v3.5"},"content":{"rendered":"

Krisp Accent Conversion v3.5 represents a significant upgrade over the previous v3.0 release. Both Indian and Filipino accent models show consistent improvements across clarity, naturalness, and pronunciation accuracy, validated through expert evaluation, crowdsourced ratings, and objective metrics. Overall, the v3.5 models deliver clearer, more natural, and more intelligible speech while preserving speaker identity.<\/p>\n

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Key Improvements in AC v3.5<\/h2>\n
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  1. Speech & Audio Clarity:<\/strong> Major improvements in intelligibility and reduction of audio artifacts and distortions. Speech Clarity scores increased by +18%<\/strong> (Indian) and +23%<\/strong> (Filipino) in expert evaluations, with consistent boosts across Meta metrics as well.<\/li>\n
  2. Naturalness & Fluidity:<\/strong> Speech sounds more human and expressive, with better rhythm, pacing, and filler sound handling. Expert-rated Natural Speech scores improved by +18%<\/strong> (Indian) and +20%<\/strong> (Filipino). Crowdsourced evaluations confirm this with +10%<\/strong> (Indian) and +6%<\/strong> (Filipino) gains.<\/li>\n
  3. Pronunciation Accuracy:<\/strong> Improved phoneme articulation and intelligibility reflected in a fairly significant 10%<\/strong> reduction in Phoneme Error Rate (PER) for the Indian accent pack.<\/li>\n
  4. Voice Stability:<\/strong> Enhanced consistency in pitch and tone throughout the utterance, helping avoid unnatural fluctuations. This contributed to improved naturalness and clarity scores across all metrics.<\/li>\n
  5. Speaker Identity Retention:<\/strong> v3.5 models better preserve the original speaker\u2019s voice characteristics, resulting in more personalized and authentic-sounding output, evident in higher naturalness ratings across both subjective and objective evaluations.<\/li>\n<\/ol>\n

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    Evaluation Results<\/h3>\n

    For subjective and objective evaluations, 78 real-world recordings were sampled for the Indian accent pack and 57 for the Filipino accent pack.<\/p>\n

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    For the crowdsourced evaluation, each recording received exactly 30 independent votes to ensure statistical confidence \u2014 2340 total votes for Indian recordings and 1710 for Filipino recordings.<\/p>\n

     <\/p>\n

    The results shown in the table below represent aggregated averages across all recordings.<\/p>\n

     <\/p>\n

    <\/p>\n\n\n\n\n\n\n\n\n\n\n
    Metric<\/th>\nIN AC v3<\/th>\nIN AC v3.5<\/th>\nPH AC v3<\/th>\nPH AC v3.5<\/th>\n<\/tr>\n<\/thead>\n
    Expert evaluation –
    \nNatural speech (1 to 5)<\/td>\n    		3.3<\/td>\n\"\"\u00a03.9 (+18%)<\/td>\n3.4<\/td>\n\"\"\u00a04.1 (+20%)<\/td>\n<\/tr>\n
    Expert evaluation –
    \nSpeech clarity (1 to 5)<\/td>\n    		3.4<\/td>\n\"\"\u00a04.0 (+18%)<\/td>\n3.4<\/td>\n\"\"\u00a04.2 (+23%)<\/td>\n<\/tr>\n
    Crowdsourced evaluation –
    \n\u201cHow natural does
    \nthe voice sound?<\/em>\u201d (1 to 5)<\/td>\n    		3.1<\/td>\n\"\"\u00a03.4 (+10%)<\/td>\n3.3<\/td>\n\"\"\u00a03.5 (+6%)<\/td>\n<\/tr>\n
    Meta Aesthetic –
    \nNatural speech (1 to 10)<\/td>\n    		5.4<\/td>\n\"\"\u00a05.6 (+4%)<\/td>\n5.4<\/td>\n\"\"\u00a05.7 (+6%)<\/td>\n<\/tr>\n
    Meta Aesthetic –
    \nSpeech clarity (1 to 10)<\/td>\n    		7.1<\/td>\n\"\"\u00a07.5 (+6%)<\/td>\n7.1<\/td>\n\"\"\u00a07.5 (+6%)<\/td>\n<\/tr>\n
    Phoneme Error Rate (PER)<\/td>\n26.1%<\/td>\n\"\"\u00a024% (\u221210%)<\/td>\n28.4%<\/td>\n= 28.4% (no change)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

     <\/p>\n

    Comparative audio samples<\/strong><\/h2>\n

    Listening Tip:<\/strong> For the most accurate and immersive comparison between v3.0 and v3.5 Accent Conversion, we recommend using quality headphones.<\/p>\n

    This helps highlight the improvements in clarity, naturalness, and speaker identity preservation that may be less perceptible on laptop or mobile speakers.<\/p>\n

    <\/p>\n

    Indian English accent pack<\/h3>\n\n\n\n\n\n\n\n\n\n
    Improvement category<\/th>\nOriginal speech<\/th>\nConverted AC V3<\/th>\nConverted AC V3.5<\/th>\n<\/tr>\n<\/thead>\n
    Voice stability<\/strong><\/p>\n

    Speech clarity<\/strong><\/p>\n

    Speech naturalness<\/strong><\/td>\n


    \n
    Voice stability<\/strong><\/p>\n

    Speech clarity<\/strong><\/p>\n

    Speech naturalness<\/strong><\/td>\n

    Speech clarity<\/strong><\/p>\n

    Speech naturalness<\/strong><\/p>\n

    <\/td>\n

    Speech clarity<\/strong><\/p>\n

    Speech naturalness<\/strong><\/p>\n

    Audio quality<\/strong><\/td>\n

    Speech clarity<\/strong><\/p>\n

    Speech naturalness<\/strong><\/td>\n