TTS API comparison 2026
Gradium TTS vs Alibaba Qwen3 TTS Gradium vs Alibaba (Qwen) · text-to-speech for voice agents
Gradium TTS is in the Headroom speed tier (P95 under 120 ms); Alibaba Qwen3 TTS is in the no speed tier (not measured by Coval). Below, each measure side by side with its source; a model leads on a measure only beyond the tie rule. No combined score, no overall winner.
Figures as of October 27, 2026 · Coval, Speko, Artificial Analysis, Cekura
Side by side
| Measure | Gradium TTS | Alibaba Qwen3 TTS |
|---|---|---|
| Speed tierCoval P95, 30 days | Headroom | not measured |
| Median time to first audioCoval, 30-day window | 54 ms | — |
| P95 time to first audio (slow turns)Coval, 30-day window | 104 ms | — |
| Time to first audio, board chartSpeko, US East | 55 ms | — |
| Time to first audio, full sentence (median)Cekura | 76 ms | 1,646 ms |
| Time to first audio, text streamed word by word (median)Cekura | -64 ms | — |
| Naturalness EloSpeko | 1,592 | not rated |
| Listener Elo (95% interval)Artificial Analysis | 1,174 ±13 | 929 ±13 |
| Numbers and dates (0 to 1)Speko | 0.27 | not rated |
| Hard passages pronounced correctly (95% interval)Artificial Analysis, human reviewers | not tested | not tested |
| Reading accuracy on hard textCekura, transcriber-scored | 79.5% | not rated |
| List price per 1M charactersCoval, Speko, Artificial Analysis, Cekura | $36 to $57.8 | $13.8 |
In bold: the model ahead on that measure. “tie”: latencies within 10 ms, or Elo scores whose 95% intervals overlap.
Where Gradium TTS is ahead
- →Time to first audio, full sentence (median): 76 ms vs 1,646 ms (Cekura)
- →Listener Elo (95% interval): 1,174 ±13 vs 929 ±13 (Artificial Analysis)
Where Alibaba Qwen3 TTS is ahead
- →List price per 1M characters: $13.8 vs $36 to $57.8 (Coval, Speko, Artificial Analysis, Cekura)
Frequently asked questions
- What is the difference between Gradium TTS and Alibaba Qwen3 TTS?
- Gradium TTS (Gradium) is in the Headroom speed tier (P95 under 120 ms); Alibaba Qwen3 TTS (Alibaba (Qwen)) is in the no speed tier (not measured by Coval). Gradium TTS leads on time to first audio, full sentence (median) and listener Elo (95% interval); Alibaba Qwen3 TTS leads on list price per 1M characters. No combined score is computed.
- Which is faster for real-time voice agents, Gradium TTS or Alibaba Qwen3 TTS?
- Only Gradium TTS is measured by Coval (median 54 ms, P95 104 ms); Alibaba Qwen3 TTS has no speed tier, so the two cannot be compared on the same window.
- Which sounds more natural, Gradium TTS or Alibaba Qwen3 TTS?
- Speko naturalness: 1,592 for Gradium TTS, not rated for Alibaba Qwen3 TTS. Artificial Analysis listener Elo: 1,174 ±13 and 929 ±13. The two sources use different listeners and can disagree.
- How are these two text-to-speech APIs compared?
- Speed first, on Coval's median and P95 time to first audio; then voice quality (Speko, Artificial Analysis), accuracy on numbers and dates (Speko) and list price. Latencies within 10 ms and Elo scores whose intervals overlap are ties. Scores from different benchmarks are never added into one number.
- Can these numbers be checked?
- Yes. Each model page lists every measurement with its source and the date of the reading, and links to the benchmark page it comes from. The rules are on the methodology page.