TTS API comparison 2026
Gradium TTS vs Alibaba Qwen3 TTS Flash Realtime 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 Flash Realtime is in the Visible delay speed tier (P95 over 293 ms). 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 Flash Realtime |
|---|---|---|
| Speed tierCoval P95, 30 days | Headroom | Visible delay |
| Median time to first audioCoval, 30-day window | 54 ms | 727 ms |
| P95 time to first audio (slow turns)Coval, 30-day window | 104 ms | 786 ms |
| Time to first audio, board chartSpeko, US East | 55 ms | — |
| Time to first audio, full sentence (median)Cekura | 76 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 | not rated |
| 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 |
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
- →Median time to first audio: 54 ms vs 727 ms (Coval, 30-day window)
- →P95 time to first audio (slow turns): 104 ms vs 786 ms (Coval, 30-day window)
Where Alibaba Qwen3 TTS Flash Realtime is ahead
- →List price per 1M characters: $13 vs $36 to $57.8 (Coval, Speko, Artificial Analysis, Cekura)
Frequently asked questions
- What is the difference between Gradium TTS and Alibaba Qwen3 TTS Flash Realtime?
- Gradium TTS (Gradium) is in the Headroom speed tier (P95 under 120 ms); Alibaba Qwen3 TTS Flash Realtime (Alibaba (Qwen)) is in the Visible delay speed tier (P95 over 293 ms). Gradium TTS leads on median time to first audio and P95 time to first audio (slow turns); Alibaba Qwen3 TTS Flash Realtime 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 Flash Realtime?
- On Coval's 30-day window as of October 27, 2026, the median time to first audio is 54 ms for Gradium TTS and 727 ms for Alibaba Qwen3 TTS Flash Realtime (Gradium TTS ahead by 673 ms); the P95, the slow turn, is 104 ms and 786 ms (Gradium TTS ahead by 682 ms). Gaps under 10 ms are ties.
- Which sounds more natural, Gradium TTS or Alibaba Qwen3 TTS Flash Realtime?
- Speko naturalness: 1,592 for Gradium TTS, not rated for Alibaba Qwen3 TTS Flash Realtime. Artificial Analysis listener Elo: 1,174 ±13 and not rated. 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.