Hume AI Overall Quality Index
Gemini 3.8 Flash TTS 0.9 leads since September 2026 Listeners rate generated speech on reliability and expressiveness. The benchmark reports an overall quality index.
Hume AI runs the evaluation. No public leaderboard was found, so numbers come from model makers' reports.
- Made by
- Hume AI
- Released
- September 2026
- Kind
- Speech recognition and translation
- Level
- Everyday
- Scored
- Ranked by votes
- Answers
- Open-ended
- Tasks
- Kept private
- Last in a launch post
- September 2026
- Last model added
- September 2026
2 models have ratings here, all from their labs’ own posts
Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs. A rating ranks a model only against others rated in the same arena at the same time, so these don’t show who leads.
- 1 Gemini 3.8 Flash TTS 0.9
- 2 Gemini 3.8 Flash-Lite TTS 0.9
Source: Labs’ model cards
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Gemini 3.8 Flash TTS | 0.9 | Sep 2026 | Lab model card | |
| 2 | Gemini 3.8 Flash-Lite TTS | 0.9 | Sep 2026 | Lab model card |
Number one over time
Lab claims count from the day the card came out, independent runs from the model’s release.
Source: Labs’ model cards
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Source: Labs’ model cards
One lab put it in a launch post in the last six months
Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.
| Date | Launch post | Score | As the post writes it |
|---|---|---|---|
| Sep 23, 2026 | Gemini 3.8 Flash TTS | 0.92 | Hume AI Text-to-Speech Quality Benchmark, Overall Reliability x Expressiveness |
2 system cards report it, from 1 lab
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| Sep 23, 2026 | Gemini 3.8 Flash TTS model card | 0.92 | Hume AI Text-to-Speech Quality Benchmark, Overall Reliability x Expressiveness, Gemini speech generation model page | Capabilities |
| Sep 23, 2026 | Gemini 3.8 Flash-Lite TTS model card | 0.914 | Hume AI Text-to-Speech Quality Benchmark, Overall Reliability x Expressiveness, Gemini speech generation model page | Capabilities |
More in Audio and video
- Video-MMMU In use 300 expert-level lecture videos with questions testing perception, comprehension and adaptation of knowledge. Accuracy.
Qwen 3.8 Max 88.7% - LVBench In use Hours-long video understanding with multiple-choice questions on reasoning, grounding and summarization. Gemini 4 Argon 91.7%
- MMVU In use 3,000 expert-annotated questions on videos across 27 disciplines. Multiple-choice and open-ended accuracy. Qwen 3.8 Max 82.4%
- MLVU In use Multi-task long video understanding (minutes to hours) with multiple-choice and generation tasks. Accuracy. Qwen 3.8 Max 90.8%
- FLEURS In use Models transcribe read speech in 102 languages built from FLoRes-101 sentences. Model cards usually report word error rate, so lower scores are better.
Phi-4-multimodal 4.00% - VoiceBench In use Spoken instructions with speaker, environment and content variation. Voice assistant responses scored by GPT judge or rules. Qwen3.5-Omni-Plus 93.1%