Cartesia Ink 2 vs Reson8
Cartesia Ink 2 is ahead on time to first text and final-text delay, and Reson8 on the Pipecat Dataset and the Ocular Dataset.
Quality and speed frontier
Every model's error rate on the public clips, against how long its transcript takes to settle.
The four metrics, side by side
Word error rate on 1,000 clips from Pipecat's STT benchmark dataset.
- Cartesia Ink 2
- 2.39%5th
- Reson8
- 2.10%3rd
Reson8, 0.29 points lower
Word error rate on eight licensed recordings provided by Ocular.
- Cartesia Ink 2
- 3.09%2nd
- Reson8
- 2.93%1st
Reson8, 0.16 points lower
Median delay before the first words arrive, from the first audio packet.
- Cartesia Ink 2
- 1.51s9th
- Reson8
- 2.40s11th
Cartesia Ink 2, 889ms sooner
Median delay after the speaker stops before the transcript is final.
- Cartesia Ink 2
- 123ms5th
- Reson8
- 235ms10th
Cartesia Ink 2, 112ms sooner
Lower is better on every metric. The small figure is each model's place in the whole field.
First text and final text, at three percentiles
Both measured on the same 206 streamed Ocular Dataset turns. P90 and P95 say what a caller meets on a bad turn, which a median hides.
| Measure | Model | P50 | P90 | P95 |
|---|---|---|---|---|
| Time to first text | Cartesia Ink 2 | 1.51s | 2.04s | 3.23s |
| Reson8 | 2.40s | 7.97s | 10.20s | |
| Final-text delay | Cartesia Ink 2 | 123ms | 139ms | 145ms |
| Reson8 | 235ms | 357ms | 398ms |
Both against every other model
Open on the metric where the two sit furthest apart, with the other three a tab away.
Final-text delay after the speaker stops. Lower is better.
| # | Model | Final text | turns | |
|---|---|---|---|---|
| 1 | Inworld STT-1 | 41ms | 206 | |
| 2 | Deepgram Nova-3 | 103ms | 202 | |
| 3 | Deepgram Flux English | 108ms | 199 | |
| 4 | Deepgram Flux Multilingual | 114ms | 175 | |
| 5 | Cartesia Ink 2 | 123ms | 198 | |
| 6 | Speechmatics Linden | 147ms | 194 | |
| 7 | AssemblyAI Universal 3.5 Pro | 180ms | 205 | |
| 8 | Smallest Pulse | 201ms | 206 | |
| 9 | Gradium | 212ms | 198 | |
| 10 | Reson8 | 235ms | 201 | |
| 11 | Google Chirp 3 | 475ms | 206 | |
| 12 | GPT Realtime Whisper | 543ms | 206 | |
| 13 | Google Chirp 2 | 568ms | 205 | |
| 14 | GPT-4o Mini Transcribe | 630ms | 206 | |
| 15 | GPT-4o Transcribe | 652ms | 206 |
Median across the same 206 Ocular Dataset turns. Providers finalize differently, so compare models with similar finalization contracts before treating small gaps as meaningful.
Both on the other two views
Pipecat vs Ocular accuracy
Every model's error rate on the public clips, against the same model on real conversations.
Transcription response time
How soon each model returns its first words, against how soon its transcript is final.
What the numbers rest on
| Model | Pipecat clips | Ocular recordings | Turns timed | Failed |
|---|---|---|---|---|
| Cartesia Ink 2 | 1,000 | 8 | 198 | 0 |
| Reson8 | 1,000 | 8 | 201 | 0 |
A clip counts only where the model returned usable text, so counts differ between models. Word error rate is measured the same way throughout: incorrect, missing, and extra words against the reference transcript.
Frequently asked questions
Is Cartesia Ink 2 or Reson8 more accurate?
On the 1,000 public Pipecat clips, Cartesia Ink 2 scores 2.39% and Reson8 2.10%, so Reson8 makes fewer errors by 0.29 points. On the eight licensed Ocular recordings, Cartesia Ink 2 scores 3.09% and Reson8 2.93%, so Reson8 makes fewer errors by 0.16 points. Word error rate counts incorrect, missing, and extra words against the reference transcript, so lower is better.
Which is faster, Cartesia Ink 2 or Reson8?
Cartesia Ink 2 returns first text 889ms sooner, at 1.51s against 2.40s at the median. Cartesia Ink 2 has the final transcript 112ms sooner, 123ms after the speaker stops against 235ms. Both are measured on the same 206 streamed turns.
How were Cartesia Ink 2 and Reson8 compared?
Both ran the same two datasets under the same conditions as every other model in the benchmark: 1,000 public clips from Pipecat's STT benchmark dataset and eight licensed conversation recordings from Ocular. Cartesia Ink 2 returned usable text for 1,000 of the public clips and Reson8 for 1,000. Latency uses each provider's own supported finalization contract.