{"observation":{"id":"e219f2da-9cfd-4b35-af38-9f5e8628329a","tool":"synthesia","tool_name":"Synthesia","criterion":"voice-cloning-quality","criterion_name":"Voice Cloning Quality","criterion_definition":"Does the dubbed voice sound natural, and does it match the original speaker's energy, tone, and style?","criterion_evidence_type":"transformation","criterion_rank_role":"decisive","criterion_rank_role_reason":"The product here depends on the dubbed voice sounding natural and resembling the original speaker, so weak voice cloning directly hurts the core task. (3 of 3 judges)","scenario":"hindi-vlog-style-talking-head-hindi-english","scenario_name":"Hindi vlog-style talking head (Hindi → English)","group_tag":"video-translation-voice-clone-lip-sync","scenario_description":"A casual Hindi/Hinglish talking-head or vlog-style creator video translated into English to stress informal language handling, slang, and natural-sounding voice cloning on real creator content.","modality":"video","input_text":null,"input_artifact_refs":[],"stresses":[],"verdict":"mixed","score":null,"score_total":null,"note":"The generated Hindi voice was clear and natural, but the output used an AI avatar instead of the original person, so it did not preserve the source speaker’s identity or style.","evidence_state":"verified","source":"first-party","artifacts":[{"url":"https://d3epheqghktydj.cloudfront.net/synthesia-input-1-fitness-video-online-video-cutter-com.mp4","role":"input","alt":"Synthesia — Input 1 Fitness Video (online-video-cutter.com).mp4"}],"run_id":"9feca581-b454-4bda-a610-a646cd0092f0","study_title":"Translate Videos with Voice Cloning and Lip Sync Using AI","study_kind":"backfill","research_task":"86b96dfpf","tested_at":"2026-06-24T05:45:24.018000+00:00","completeness":"input-only","input":{"state":"not-captured","text":null,"files":[],"modality":"video","stresses":[]},"tool_page_slug":"synthesia","tool_url":"https://aidemos.com/tools/synthesia","permalink":"https://aidemos.com/evidence/e219f2da-9cfd-4b35-af38-9f5e8628329a","api_url":"https://ai.aidemos.com/v1/observations/e219f2da-9cfd-4b35-af38-9f5e8628329a"},"peers":[{"id":"be692751-8937-4f24-b417-17444353cf60","tool":"dubverse","tool_name":"Dubverse","verdict":"worked","score":null,"score_total":null,"note":"Produces a natural, professional-sounding voice that fits neutral educational narration.","artifact_count":2,"thumbnail":"https://d3epheqghktydj.cloudfront.net/dubverse-input-2-educational.mp4","evidence_url":"https://aidemos.com/evidence/be692751-8937-4f24-b417-17444353cf60"},{"id":"ed554b4b-daf1-40eb-87de-acd4682ef325","tool":"elevenlabs","tool_name":"ElevenLabs","verdict":"worked","score":null,"score_total":null,"note":"The dubbed voice was reported as very high quality: natural, human-like, expressive, and especially strong for energetic fitness instruction delivery.","artifact_count":2,"thumbnail":"https://d3epheqghktydj.cloudfront.net/elevenlabs-input-1-fitness-video-online-video-cutter-com.mp4","evidence_url":"https://aidemos.com/evidence/ed554b4b-daf1-40eb-87de-acd4682ef325"},{"id":"93225df6-a800-4a70-91b5-cd29e8e95ceb","tool":"heygen","tool_name":"Heygen","verdict":"mixed","score":null,"score_total":null,"note":"The dubbed voice sounds slightly robotic rather than fully natural.","artifact_count":1,"thumbnail":"https://d3epheqghktydj.cloudfront.net/heygen-input-2-educational.mp4","evidence_url":"https://aidemos.com/evidence/93225df6-a800-4a70-91b5-cd29e8e95ceb"},{"id":"0f2ee47f-ad28-4219-b248-be9132486c45","tool":"rask-ai","tool_name":"Rask AI","verdict":"mixed","score":null,"score_total":null,"note":"Creates a clear English dubbed voice, but it does not fully match the original speaker's personality and can feel generic.","artifact_count":1,"thumbnail":"https://d3epheqghktydj.cloudfront.net/rask-ai-free-copyright-stock-videos-images-and-music-publer-com-online-video-cutter-com.mp4","evidence_url":"https://aidemos.com/evidence/0f2ee47f-ad28-4219-b248-be9132486c45"},{"id":"c3394629-5f26-4aca-a85b-87003a633f50","tool":"sync-labs","tool_name":"Sync Labs","verdict":"struggled","score":null,"score_total":null,"note":"The dubbed voice sounded generic and lacked personality, so the voice cloning was not convincing for a conversational vlog.","artifact_count":2,"thumbnail":"https://d3epheqghktydj.cloudfront.net/sync-labs-free-copyright-stock-videos-images-and-music-publer-com-online-video-cutter-com.mp4","evidence_url":"https://aidemos.com/evidence/c3394629-5f26-4aca-a85b-87003a633f50"}],"other_criteria":[{"id":"bd6e43a8-a839-4918-b1da-1cb8ecbf13b1","criterion":"output-quality-export","criterion_name":"Output Quality & Export","rank_role":"context","verdict":"failed","score":null,"score_total":null,"note":"Export was limited to paid access, so the final result was not freely downloadable as a clean, unrestricted export.","artifact_count":1,"evidence_url":"https://aidemos.com/evidence/bd6e43a8-a839-4918-b1da-1cb8ecbf13b1"},{"id":"f7271f03-e4f1-4549-b5c5-2be260da9484","criterion":"output-quality-export","criterion_name":"Output Quality & Export","rank_role":"context","verdict":"failed","score":null,"score_total":null,"note":"Export was restricted without a paid plan, so the final video is not freely downloadable in a production-ready way on this test.","artifact_count":1,"evidence_url":"https://aidemos.com/evidence/f7271f03-e4f1-4549-b5c5-2be260da9484"},{"id":"b1cc7512-fcf0-4f24-a52a-05286b3da77b","criterion":"output-quality-export","criterion_name":"Output Quality & Export","rank_role":"context","verdict":"failed","score":null,"score_total":null,"note":"Although the avatar output was described as professional-looking, export was restricted to the paid plan or limited trial and there was no reliable free download.","artifact_count":1,"evidence_url":"https://aidemos.com/evidence/b1cc7512-fcf0-4f24-a52a-05286b3da77b"},{"id":"9e0d1ab3-8778-4f60-a7eb-e6e29596a4f4","criterion":"translation-accuracy","criterion_name":"Translation Accuracy","rank_role":"decisive","verdict":"worked","score":null,"score_total":null,"note":"The Hindi translation preserved the source meaning accurately for the fitness short.","artifact_count":1,"evidence_url":"https://aidemos.com/evidence/9e0d1ab3-8778-4f60-a7eb-e6e29596a4f4"},{"id":"efb14767-e1eb-4dfd-ae5c-751c213331e3","criterion":"translation-accuracy","criterion_name":"Translation Accuracy","rank_role":"decisive","verdict":"mixed","score":null,"score_total":null,"note":"The English translation was semantically accurate, but the output shifted the casual vlog register toward a slightly more formal tone.","artifact_count":1,"evidence_url":"https://aidemos.com/evidence/efb14767-e1eb-4dfd-ae5c-751c213331e3"},{"id":"030c9db7-f816-43d2-b027-776df036ad69","criterion":"translation-accuracy","criterion_name":"Translation Accuracy","rank_role":"decisive","verdict":"worked","score":null,"score_total":null,"note":"The Spanish output was reported as accurate and well-structured, showing that the tool can preserve educational content clearly during translation.","artifact_count":1,"evidence_url":"https://aidemos.com/evidence/030c9db7-f816-43d2-b027-776df036ad69"}],"appears_in":[{"page_type":"ranking","slug":"ai-video-dubbing-tools","title":"Best AI Tools to Translate Videos with Voice Cloning and Lip Sync","url":"https://aidemos.com/best/ai-video-dubbing-tools","binding":"run"}],"same_scenario":[{"id":"be692751-8937-4f24-b417-17444353cf60","tool":"dubverse","tool_name":"Dubverse","verdict":"worked","score":null,"score_total":null,"note":"Produces a natural, professional-sounding voice that fits neutral educational narration."},{"id":"ed554b4b-daf1-40eb-87de-acd4682ef325","tool":"elevenlabs","tool_name":"ElevenLabs","verdict":"worked","score":null,"score_total":null,"note":"The dubbed voice was reported as very high quality: natural, human-like, expressive, and especially strong for energetic fitness instruction delivery."},{"id":"93225df6-a800-4a70-91b5-cd29e8e95ceb","tool":"heygen","tool_name":"Heygen","verdict":"mixed","score":null,"score_total":null,"note":"The dubbed voice sounds slightly robotic rather than fully natural."},{"id":"0f2ee47f-ad28-4219-b248-be9132486c45","tool":"rask-ai","tool_name":"Rask AI","verdict":"mixed","score":null,"score_total":null,"note":"Creates a clear English dubbed voice, but it does not fully match the original speaker's personality and can feel generic."},{"id":"c3394629-5f26-4aca-a85b-87003a633f50","tool":"sync-labs","tool_name":"Sync Labs","verdict":"struggled","score":null,"score_total":null,"note":"The dubbed voice sounded generic and lacked personality, so the voice cloning was not convincing for a conversational vlog."}]}