Official provider results
Gemini 3.8 TTS launch evaluation
Google’s September 23 launch post reports Hume voice-design and quality placements for Gemini 3.8 Flash TTS and Flash-Lite TTS.
Source snapshots refreshed
Five measurement lanesVOICE / S2S
Reasoning, task completion, conversation dynamics, experience, and latency stay separate.
Benchmark profile
- Scope
- Hume Voice Design Benchmark, accent modeling, and Overall Quality Index, as reported by Google in its launch post
- Primary metric
- Provider-reported voice quality and design results (higher is better)
- Owner
- Google DeepMind
- Available evidence
- Google states the Flash TTS design and accent scores and the two quality-index placements in prose; it does not state Flash-Lite’s underlying quality score.
What it measures
Voice experience
Is the exchange natural, robust, and responsive?
Available results
- Gemini 3.8 Flash TTS · Hume Voice Design Benchmark
- 71.4
- Gemini 3.8 Flash TTS · Hume accent modeling
- 60.8
- Gemini 3.8 Flash TTS · Hume Overall Quality Index
- #1
- Gemini 3.8 Flash-Lite TTS · Hume Overall Quality Index
- #2
#1
Google-reported overall voice-design result.
#1
Google-reported accent-modeling result.
Score not stated
Google reports the placement without an exact quality-index score in the launch prose.
Score not stated
Google reports the placement without an exact quality-index score in the launch prose.
Interpretation limit
These are Google-reported placements on third-party Hume evaluations, not independently verified results in this catalog. Flash-Lite has no published exact quality-index value in the launch prose. Voice evaluations remain separate from weighted text-model rankings.