whatmodel.sh / tts / Sonic 2

Sonic 2

+ contribute
Update model informationAdd a place to run itAdd a test resultPropose a benchmarkCorrect a benchmark scoreEdit data on GitHub

Sonic 2 is a closed-weights text-to-speech model from Cartesia, released March 2025. Licence: proprietary.

Catalogue identity notes

Vapi registry cartesia-sonic-2, apiModelId sonic-2. Rating-only comparison identity; no price, API or run metadata asserted.

57.6±2.6comparison only: no current run option verifiedfrom 2 benchmark results across 2 sources* thinly tested, treat the rank as provisional

Score within the Vapi Humanness · Bradley–Terry rating, 2026-09-25 snapshot comparison set only.

$ how it compares

The text-to-speech models ranked either side of Sonic 2, out of 148 with a score, then more from Cartesia.

#modelscorewhereRAMreleased
57Sonic 3 Cartesia58±2api $65.00/M chars2025-10
58GPT-4o mini TTS OpenAI58±2comparison only2025-03
59Sonic 2 Cartesia58±3comparison only2025-03
60F5-TTS Base (v0) SWivid (SJTU X-LANCE)57±2local~1.4GB2024-10
61TTS-1 HD OpenAI57±7api $30.00/M chars2023-11
more from Cartesia
35Sonic 3.5 Cartesia63±2comparison only2026-05
105Sonic (1) Cartesia42±3comparison only2024-05

see all text-to-speech models · find the ones that fit your machine

$ what it's good at

other tests2 not in a task · 97% of its score
testresultvs the others in its rundifficultycountswhy
Vapi Humanness · Bradley–Terry rating, 2026-09-25 snapshot1185.1 ✎▁···▁▃··█▄▁▇ beats 4/18avg 1078▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇ 64%typical
Vapi Humanness · historical Elo, 2026-06-101139.6 ✎▃·▃▃▃·▃██▃·▃ beats 3/12avg 1080▇▇▇▇▇▇▇▇▇▇▇▇▇ 33%typical

$ where to run it

No verified API or download recorded yet · add one

$ how the score was worked out · The Humanness Index by Vapi ·… 64%, The Humanness Index by Vapi ·… 33%

Each result implies a score on its own, after adjusting for how hard its test is and who ran it. The score is their weighted average, with a small pull toward the middle for thinly tested models. Each test's weight is its counts column above; here it's added up by who ran the tests. How it works

sourceresultsshare of the scorelicence
The Humanness Index by Vapi · September 2026 public standings1▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇ 64%CC BY 4.0
The Humanness Index by Vapi · June 2026 production export1▇▇▇▇▇▇▇▇▇▇ 33%CC BY 4.0
prior · pull toward the middle▇ 3%
weighted average= 57.6

$ improve this page

Update model informationAdd a place to run itAdd a test resultPropose a benchmarkCorrect a benchmark scoreEdit data on GitHub

Use a short GitHub form or edit the data through a pull request. Every number needs a source; here's which ones we can use.

data updated · sources and licences · json