dots.tts is a 2B-parameter fully continuous, end-to-end autoregressive (AR) text-to-speech system. The backbone pairs a semantic encoder, an LLM, and an autoregressive flow-matching acoustic head over a 48 kHz AudioVAE, with no discrete tokens anywhere in the pipeline.
dots.tts achieves the best average performance on Seed-TTS-Eval, with WERs of 0.94% / 1.30% / 6.60% and SIM scores of 81.0 / 77.1 / 79.5 on the zh / en / zh-hard test sets, respectively. It further attains the highest average speaker similarity (83.9) on the 24-language MiniMax multilingual benchmark. Across other benchmarks, dots.tts also consistently demonstrates open-source state-of-the-art performance, exhibiting strong generation stability, voice cloning ability, and emotional expressiveness.
-
[2026.08] 🚀 SGLang Omni now fully supports dots.tts (
mf/soar/base) with continuous batching, streaming PCM, and CUDA-graph decode. On Seed-TTS-Eval EN (1× H100,dots.tts-mf,num_steps=4), peak throughput reaches 4.64 req/s / 19.36 audio_s/s at concurrency 16 (WER 1.31%). See SGLang Omni Usage and the cookbook. -
[2026.07] 🚀 Shipped a high-performance inference path — under
--optimize,dots.tts-soarreaches RTF p50 0.20 / 0.18 and first-chunk latency 225 ms / 69 ms (voice cloning / text-only);dots.tts-mfreaches 0.15 / 0.13 and 204 ms / 68 ms respectively. See the Efficiency section for details. -
[2026.06] 🔥 We have released dots.tts — 2B fully continuous AR TTS, with pretrained / self-corrective-aligned / MeanFlow-distilled checkpoints and full inference & fine-tuning code under Apache-2.0.
- Quick Start
- Usage Tips
- Architecture
- Performance
- Efficiency
- Community Projects
- Risks and Limitations
- Citation
- License
We recommend a fresh conda environment (Python 3.10–3.12):
conda create -n dots_tts python=3.10 -y
conda activate dots_ttsInstall from PyPI:
pip install dots.ttsOr from source (for local development / editable install):
git clone https://github.com/rednote-hilab/dots.tts
cd dots.tts
pip install -e . -c constraints/recommended.txtFor training / linting extras:
pip install 'dots.tts[full]'
# or from source:
pip install -e .[full] -c constraints/recommended.txtThe constraints/recommended.txt file pins the reproducible versions;
pyproject.toml declares compatibility ranges.
To use SGLang Omni for high-performance high-concurrency voice cloning:
git clone git@github.com:sgl-project/sglang-omni.git
cd sglang-omni
uv venv .venv -p 3.12
source .venv/bin/activate
uv pip install -v -e .Detailed installation instructions can be found in this guidance.
Three pretrained checkpoints are released on Hugging Face. All three share the same backbone — choose by the quality / inference-cost tradeoff:
| Model | Description | Recommended --num-steps |
|---|---|---|
rednote-hilab/dots.tts-base |
Pretrained checkpoint. | 10–32 (default 10) |
rednote-hilab/dots.tts-soar |
Self-corrective-aligned (SCA) checkpoint on top of dots.tts-base. Best voice cloning performance. |
10–32 (default 10) |
rednote-hilab/dots.tts-mf |
MeanFlow-distilled student from dots.tts-soar. Recommended if you care about inference speed. |
4 |
Pass the repo id directly to --model-name-or-path (or DotsTtsRuntime.from_pretrained) — the snapshot is fetched on first use and cached locally.
The package installs a dots.tts entry point:
# Continuation voice cloning (reference audio + transcript) — recommended, best SIM
dots.tts \
--model-name-or-path rednote-hilab/dots.tts-soar \
--text "Hello, this is a zero-shot voice cloning demonstration." \
--prompt-audio /path/to/reference.wav \
--prompt-text "The exact transcript of the reference audio." \
--num-steps 10 \
--output clone.wav
# X-vector-only voice cloning (reference audio only — timbre from speaker x-vector)
dots.tts \
--model-name-or-path rednote-hilab/dots.tts-soar \
--text "Hello, this is a zero-shot voice cloning demonstration." \
--prompt-audio /path/to/reference.wav \
--num-steps 10 \
--output clone.wav
# Random-voice sampling (no reference) — only meaningful with a fine-tuned
# single-speaker checkpoint
dots.tts \
--model-name-or-path rednote-hilab/dots.tts-soar \
--text "Hello, this is a quick speech synthesis test." \
--num-steps 10 \
--output output.wavCommon flags:
| Flag | Description | Default |
|---|---|---|
--num-steps |
Flow-matching sampling steps (higher = better quality, lower = faster) | 10 |
--guidance-scale |
CFG scale (flow-matching only; MeanFlow has CFG fused into the student; values > 2 progressively amplify audio energy) | 1.2 |
--normalize-text |
Apply text normalization before inference (via WeTextProcessing) | off |
--language |
Add an explicit language tag to the input text; accepts none, auto_detect, language codes such as EN / ZH, or names such as english / chinese |
none |
--seed |
RNG seed (fixed seed → deterministic output) | 42 |
dots.tts --help lists the full set.
Notes:
--prompt-audioselects the speaker voice — continuation cloning when paired with--prompt-text, x-vector-only cloning when used alone. Omitting--prompt-audiofalls back to random-voice sampling, which is only meaningful on a fine-tuned single-speaker checkpoint.--languageis useful for multilingual or code-switched text when you want to force the model-side language tag. For example, pass--language ENfor English,--language ZHfor Mandarin,--language Cantonesefor Cantonese, or--language auto_detectto infer the tag from--text.- Pass either a local model directory or a Hugging Face repo id.
from dots_tts.runtime import DotsTtsRuntime
import soundfile as sf
runtime = DotsTtsRuntime.from_pretrained(
"rednote-hilab/dots.tts-soar",
precision="bfloat16",
optimize=True, # torch.compile acceleration (warmup at load, faster steady-state)
)
result = runtime.generate(
text="Hello, this is a quick speech synthesis test.",
prompt_audio_path="/path/to/reference.wav",
prompt_text="The exact transcript of the reference audio.",
num_steps=10,
guidance_scale=1.2,
)
sf.write("output.wav", result["audio"].float().cpu().squeeze().numpy(), result["sample_rate"])For low-latency playback or streaming to a client, use generate_stream instead — it yields audio chunks (torch.Tensor, shape (1, samples)) as they are produced. Arguments are identical to generate:
import torch
stream = runtime.generate_stream(
text="Hello, this is a streaming speech synthesis test.",
prompt_audio_path="/path/to/reference.wav",
prompt_text="The exact transcript of the reference audio.",
num_steps=10,
guidance_scale=1.2,
)
chunks = []
for chunk in stream:
chunks.append(chunk.detach().float().cpu())
# handle_chunk(chunk) # push to a player / websocket / etc.
audio = torch.cat(chunks, dim=-1).squeeze().numpy()
sf.write("output_stream.wav", audio, runtime.sample_rate)python apps/gradio/app.py \
--model-name-or-path rednote-hilab/dots.tts-soar \
--optimizeDefaults to http://0.0.0.0:7860. With --optimize the first launch runs warmup (slower startup, faster steady-state).
This repo exposes fine-tuning and MeanFlow distillation entry points. Fine-tune from a released checkpoint with:
accelerate launch scripts/train_dots_tts.py --config configs/dots_tts.yamlconfigs/dots_tts.yaml is a smoke configuration that verifies the pipeline runs end-to-end on commodity hardware. Replace train.pretrained_model_path, train_data.sources / val_data.sources, train.output_dir, and train.max_train_steps with your own values to use it.
A helper script downloads LJSpeech-1.1-48kHz and emits a train/valid JSONL manifest for the smoke run:
python scripts/prepare_train_jsonl_manifest.py --output-dir downloaded_dataManifest format — one JSON per line, minimum three fields:
{"fid": "sample-0001", "audio": "/abs/path/to/audio.wav", "text": "hello world"}MeanFlow distillation trains a MeanFlow DiT student against a frozen flow-matching teacher. The teacher can be the released SOAR checkpoint or any compatible flow-matching dots.tts checkpoint you have fine-tuned yourself.
To use SOAR as the teacher, download it first:
huggingface-cli download rednote-hilab/dots.tts-soar \
--local-dir pretrained_models/dots.tts-soarThen launch distillation with the MeanFlow config:
accelerate launch \
--num_processes 2 \
--mixed_precision bf16 \
scripts/train_dots_tts_meanflow.py \
--config configs/dots_tts_meanflow.yaml \
--teacher-model-path pretrained_models/dots.tts-soarTo distill from your own fine-tuned teacher, pass that checkpoint instead:
accelerate launch \
--num_processes 2 \
--mixed_precision bf16 \
scripts/train_dots_tts_meanflow.py \
--config configs/dots_tts_meanflow.yaml \
--teacher-model-path /path/to/your_finetuned_teacherconfigs/dots_tts_meanflow.yaml is a conservative smoke configuration that uses the same LJSpeech manifests produced by scripts/prepare_train_jsonl_manifest.py. Replace train.pretrained_model_path, --teacher-model-path, train_data.sources / val_data.sources, train.output_dir, and train.max_train_steps for your own distillation run.
By default, the script initializes the student from train.pretrained_model_path, adds the MeanFlow duration embedding, freezes the non-DiT modules, and trains student.core.velocity_field_predictor. MeanFlow does not run a separate CFG branch at inference time; the default fused mode distills the guided teacher target into the student. Training checkpoints save the MeanFlow student only; the frozen teacher is not written into the checkpoint model directory. Pass --train-all-parameters only if you want to update the full dots.tts model.
Common MeanFlow flags:
| Flag | Description | Default |
|---|---|---|
--teacher-model-path |
Frozen flow-matching teacher directory. Defaults to train.pretrained_model_path if omitted. |
train.pretrained_model_path |
--teacher-steps |
Teacher rollout steps used to build the distillation target. Higher is slower and usually stronger. | 8 |
--teacher-solver |
Teacher ODE solver: euler, midpoint, or rk4. |
euler |
--cfg-distill-mode |
fused distills a guided teacher target into the student; natural trains on sampled conditional/unconditional masks without fusing CFG. |
fused |
--distill-cfg-scale |
Extra CFG coefficient used when --cfg-distill-mode fused is enabled. It matches inference guidance_scale semantics: teacher_cond + scale * (teacher_cond - teacher_uncond). |
1.2 |
--anchor-prob |
Probability of using a zero-duration anchor sample in MeanFlow training. | 0.5 |
--debug |
Print the first few batch summaries and gradient diagnostics. | off |
SGLang Omni serves dots.tts behind an OpenAI-compatible /v1/audio/speech API with continuous batching (MeanFlow), streaming PCM, and CUDA-graph backbone decode. Full details live in the SGLang Omni dots.tts cookbook.
Install Omni as in SGLang Omni Installation, then from the sglang-omni checkout:
hf download dots-studio/dots.tts-mf
sgl-omni serve \
--model-path dots-studio/dots.tts-mf \
--config examples/configs/dots_tts.yaml \
--port 8000| Checkpoint | Omni config | Notes |
|---|---|---|
dots-studio/dots.tts-mf |
examples/configs/dots_tts.yaml |
MeanFlow. Continuous batching (max_running_requests=16), num_steps=4. Recommended for serving. |
dots-studio/dots.tts-soar |
examples/configs/dots_tts_soar.yaml |
Flow matching + CFG. Single request at a time (max_running_requests=1), num_steps=10. |
dots-studio/dots.tts-base |
examples/configs/dots_tts_soar.yaml |
Same as SOAR; pass --model-path dots-studio/dots.tts-base. |
rednote-hilab/dots.tts-* weights are interchangeable via --model-path. Use the config file — it enables the compiled acoustic tail / vocoder and backbone decode CUDA graph. Continuous batching is MeanFlow-only.
Voice cloning (reference audio + transcript required):
curl -X POST http://localhost:8000/v1/audio/speech \
-H "Content-Type: application/json" \
-d '{
"model": "dots-studio/dots.tts-mf",
"input": "Have a nice day and enjoy south california sunshine.",
"references": [{
"audio_path": "docs/_static/audio/male-voice.wav",
"text": "Hey, Adam here. Let'\''s create something that feels real, sounds human, and connects every time."
}],
"seed": 42
}' \
--output output.wavimport requests
resp = requests.post(
"http://localhost:8000/v1/audio/speech",
json={
"model": "dots-studio/dots.tts-mf",
"input": "Have a nice day and enjoy south california sunshine.",
"references": [{
"audio_path": "docs/_static/audio/male-voice.wav",
"text": "Hey, Adam here. Let's create something that feels real, sounds human, and connects every time.",
}],
"seed": 42,
},
)
resp.raise_for_status()
with open("output.wav", "wb") as f:
f.write(resp.content)ref_audio / ref_text are accepted as a shorthand for references[0].audio_path / references[0].text.
Streaming (raw 48 kHz PCM; set "stream": true and "response_format": "pcm"):
curl -N -X POST http://localhost:8000/v1/audio/speech \
-H "Content-Type: application/json" \
-d '{
"model": "dots-studio/dots.tts-mf",
"input": "Get the trust fund to the bank early.",
"references": [{
"audio_path": "docs/_static/audio/female-voice.wav",
"text": "By repeating what students say, teachers can demonstrate that they are listening. By extending what students say."
}],
"stream": true,
"response_format": "pcm",
"seed": 42
}' \
--output output.pcm
ffmpeg -f s16le -ar 48000 -ac 1 -i output.pcm output.wavSolver knobs (speaker_scale, guidance_scale, eos_threshold, num_steps, …) go under stage_params.latent_engine — not as top-level fields. temperature / top_p / top_k do not apply (continuous latent; no token sampler). MeanFlow fixes num_steps=4 engine-wide for continuous batching.
- Keep the reference audio around 10s. Longer audio won't yield better results.
--prompt-textshould match what's actually spoken in the reference audio. Mismatches degrade stability and may cause word-level errors.- Higher-quality references give better clones — prefer a high sample rate, low background noise, no trailing noise, and natural-sounding speech.
- Try different
--seedvalues for prosody variation. Each seed produces a different rhythm and intonation — resample a few times if the default doesn't feel right. - Increase
--num-stepsif quality isn't good enough. More sampling steps trade compute for cleaner output and better expressiveness. - Force a pronunciation with Pinyin for polyphones. Replace the character in the input text with its tone-marked pinyin — e.g. write
我生平不hào此道to force好to be read ashào. Use tone-marked pinyin only (hǎo,hào,bā); numbered forms likehao4orha4oare not recognized. Useful when reseeding doesn't fix a polyphone misread.
A frozen AudioVAE encodes 48 kHz mono waveform into a continuous latent and decodes it back via a BigVGAN-style causal decoder. An autoregressive backbone predicts that latent one patch at a time, in three components:
- Semantic encoder — re-encodes each newly generated VAE patch into a compact embedding for the LLM, stripping high-variance acoustic detail.
- LLM — initialized from Qwen2.5-1.5B-Base, consumes BPE text directly (no phonemes), and emits one hidden state per audio step.
- AR flow-matching head — a DiT that conditions on the LLM hidden state and the AR prefix to denoise the next VAE patch, with a frozen CAM++ speaker x-vector as side input.
Two sequence layouts: plain mode places the full text as a prefix before the audio span (standard TTS); 1T1A interleaved mode alternates one BPE token with one audio step, enabling low-latency streaming when driven by a duplex dialogue LLM. See the technical report for full architectural and training details.
Baselines are taken from original publications or default-configuration open-source releases.
Zero-shot, ~3 s reference prompt, scored by the benchmark's reference ASR and WavLM-SV similarity.
| Model | Params | test-en WER↓ / SIM↑ | test-zh WER↓ / SIM↑ | test-zh-hard WER↓ / SIM↑ | Avg WER↓ / SIM↑ |
|---|---|---|---|---|---|
| CosyVoice 3 | 1.5B | 2.22 / 72.0 | 1.12 / 78.1 | 5.83 / 75.8 | 3.06 / 75.3 |
| DiTAR | 0.6B | 1.69 / 73.5 | 1.02 / 75.3 | — | — |
| F5-TTS | 0.3B | 2.00 / 67.0 | 1.53 / 76.0 | 8.67 / 71.3 | 4.10 / 71.4 |
| FireRedTTS-2 | 1.5B | 1.95 / 66.5 | 1.14 / 73.6 | 8.98 / 70.3 | 4.02 / 70.1 |
| IndexTTS 2 | 1.5B | 2.23 / 70.6 | 1.03 / 76.5 | 7.12 / 75.5 | 3.46 / 74.2 |
| MegaTTS 3 | 0.5B | 2.79 / 77.1 | 1.52 / 79.0 | — | — |
| MiniMax-Speech | — | 1.65 / 69.2 | 0.83 / 78.3 | — | — |
| Qwen3-TTS | 1.7B | 1.23 / 71.7 | 1.22 / 77.0 | 6.76 / 74.8 | 3.07 / 74.5 |
| Seed-TTS | — | 2.25 / 76.2 | 1.12 / 79.6 | 7.59 / 77.6 | 3.65 / 77.8 |
| VibeVoice | 1.5B | 3.04 / 68.9 | 1.16 / 74.4 | — | — |
| VoxCPM 2 | 2B | 1.84 / 75.3 | 0.97 / 79.5 | 8.13 / 75.3 | 3.65 / 76.7 |
| dots.tts (Pretrain) | 2B | 1.34 / 76.8 | 0.96 / 80.5 | 6.46 / 79.2 | 2.92 / 78.8 |
| dots.tts (SCA) | 2B | 1.30 / 77.1 | 0.94 / 81.0 | 6.60 / 79.5 | 2.95 / 79.2 |
| dots.tts (MF, NFE=4) | 2B | 1.29 / 76.2 | 0.94 / 80.0 | 6.60 / 78.5 | 2.94 / 78.2 |
Per-language WER / SIM on the MiniMax-Speech multilingual test set (100 utterances × 2 reference speakers per language). Highest average SIM (83.9, SCA), with a dots.tts variant taking the per-language SIM lead outright on 19 of 24 languages and tying on 2 more. Content fidelity is on par with the strongest systems on high-resource / Western European splits, and trails on low-resource long-tail languages where SIM is still preserved.
Per-language WER / SIM (click to expand)
| Language | MiniMax | ElevenLabs | Fish-Audio S2 | VoxCPM 2 | dots.tts (Pre.) | dots.tts (SCA) | dots.tts (MF$_4$) |
|---|---|---|---|---|---|---|---|
| Arabic | 1.67 / 73.6 | 1.67 / 70.6 | 3.50 / 75.0 | 13.05 / 79.1 | 37.91 / 77.5 | 36.19 / 79.1 | 39.65 / 77.6 |
| Cantonese* | 34.11 / 77.8 | 51.51 / 67.0 | 30.67 / 80.5 | 38.58 / 83.5 | 37.91 / 84.7 | 42.32 / 85.0 | 37.82 / 84.0 |
| Chinese | 2.25 / 78.0 | 16.03 / 67.7 | 0.73 / 81.6 | 1.14 / 82.5 | 1.08 / 82.3 | 0.77 / 82.5 | 1.01 / 81.8 |
| Czech | 3.88 / 79.6 | 2.11 / 68.5 | 2.84 / 79.8 | 24.13 / 78.3 | 5.05 / 83.8 | 4.25 / 84.2 | 5.67 / 83.9 |
| Dutch | 1.14 / 73.8 | 0.80 / 68.0 | 0.99 / 73.0 | 0.91 / 80.8 | 1.20 / 81.4 | 1.39 / 82.2 | 1.30 / 82.1 |
| English | 2.16 / 75.6 | 2.34 / 61.3 | 1.62 / 79.7 | 2.29 / 85.4 | 1.06 / 86.9 | 1.03 / 87.5 | 1.09 / 86.9 |
| Finnish | 4.67 / 83.5 | 2.96 / 75.9 | 3.33 / 81.9 | 2.63 / 89.0 | 3.44 / 88.0 | 4.08 / 88.3 | 3.61 / 88.3 |
| French | 4.10 / 62.8 | 5.22 / 53.5 | 3.05 / 69.8 | 4.53 / 73.5 | 3.82 / 78.2 | 3.56 / 78.6 | 3.26 / 78.5 |
| German | 1.91 / 73.3 | 0.57 / 61.4 | 0.55 / 76.7 | 0.68 / 80.3 | 1.03 / 79.5 | 1.70 / 80.6 | 0.91 / 79.5 |
| Greek | 2.02 / 82.6 | 0.99 / 73.3 | 5.74 / 79.5 | 2.84 / 86.0 | 2.97 / 87.6 | 3.00 / 87.6 | 3.19 / 87.3 |
| Hindi | 6.96 / 81.8 | 5.83 / 73.0 | 14.64 / 82.1 | 19.70 / 85.6 | 14.32 / 84.5 | 14.24 / 84.7 | 14.75 / 84.8 |
| Indonesian | 1.24 / 72.9 | 1.06 / 66.0 | 1.46 / 76.3 | 1.08 / 80.0 | 2.71 / 80.8 | 2.96 / 80.8 | 3.91 / 81.2 |
| Italian | 1.54 / 69.9 | 1.74 / 57.9 | 1.27 / 74.7 | 1.56 / 78.0 | 3.16 / 84.5 | 3.12 / 84.7 | 2.16 / 84.3 |
| Japanese | 3.52 / 77.6 | 10.65 / 73.8 | 2.76 / 79.6 | 4.63 / 82.8 | 7.16 / 83.1 | 5.28 / 83.7 | 5.17 / 83.1 |
| Korean | 1.75 / 77.6 | 1.87 / 70.0 | 1.18 / 81.7 | 1.96 / 83.3 | 5.30 / 84.3 | 5.66 / 83.6 | 3.93 / 84.9 |
| Polish | 1.42 / 80.2 | 0.77 / 72.9 | 1.26 / 81.9 | 1.14 / 88.4 | 2.72 / 87.3 | 3.59 / 87.8 | 3.42 / 87.5 |
| Portuguese | 1.88 / 80.5 | 1.33 / 71.1 | 1.14 / 78.1 | 1.94 / 83.7 | 1.64 / 83.1 | 2.00 / 84.3 | 2.40 / 83.1 |
| Romanian | 2.88 / 80.9 | 1.35 / 69.9 | 10.74 / 73.3 | 21.58 / 79.7 | 3.36 / 86.2 | 3.87 / 87.1 | 3.38 / 86.1 |
| Russian | 4.28 / 76.1 | 3.88 / 67.6 | 2.40 / 79.0 | 3.63 / 81.1 | 3.64 / 83.0 | 4.28 / 83.2 | 4.42 / 83.2 |
| Spanish | 1.03 / 76.2 | 1.08 / 61.5 | 0.91 / 77.6 | 1.44 / 83.1 | 0.96 / 83.9 | 1.27 / 84.0 | 0.80 / 84.0 |
| Thai | 2.70 / 80.0 | 73.94 / 58.8 | 4.23 / 78.6 | 2.96 / 84.0 | 7.45 / 83.8 | 7.86 / 83.9 | 8.03 / 84.2 |
| Turkish | 1.52 / 77.9 | 0.70 / 59.6 | 0.87 / 83.5 | 0.82 / 87.1 | 5.45 / 87.4 | 4.96 / 87.3 | 6.20 / 86.8 |
| Ukrainian | 1.08 / 73.0 | 1.00 / 64.7 | 2.30 / 74.7 | 6.32 / 79.8 | 1.61 / 80.5 | 1.27 / 81.2 | 1.66 / 80.0 |
| Vietnamese | 0.88 / 74.3 | 73.42 / 36.9 | 7.41 / 74.0 | 3.31 / 80.6 | 3.85 / 80.7 | 3.89 / 81.6 | 5.43 / 80.5 |
| Average | 2.8 / 76.6 | 7.5 / 65.5 | 3.7 / 78.0 | 5.7 / 82.3 | 6.6 / 83.5 | 6.8 / 83.9 | 6.8 / 83.5 |
*Cantonese WER reflects an ASR-faithfulness floor common to all systems; SIM remains comparable.
Hard-subset Chinese/English plus a cross-lingual voice-cloning split. Takes the table top on hard-en (MF$_4$ at 4.37) and leads both cross-lingual SIM subsets (SCA at 75.0 / 72.8), with the post-trained variants bracketing the prior leader on the hardest English subset.
| Model | zh W↓ | en W↓ | hard-zh W↓ | hard-en W↓ | en→zh W↓ / S↑ | zh→en W↓ / S↑ |
|---|---|---|---|---|---|---|
| CosyVoice 2 | 4.08 | 6.32 | 12.58 | 11.96 | 13.50 / 63.3 | 6.47 / 64.3 |
| CosyVoice 3 (1.5B) | 3.91 | 4.99 | 9.77 | 10.55 | 8.01 / 66.9 | 4.32 / 66.4 |
| Fish-Audio S2 | 2.65 | 2.43 | 9.10 | 4.40 | — | — |
| VoxCPM 2 | 3.65 | 5.00 | 8.55 | 8.48 | — | — |
| dots.tts (Pretrain) | 3.51 | 5.24 | 9.69 | 5.99 | 10.88 / 74.6 | 4.97 / 71.9 |
| dots.tts (SCA) | 3.71 | 4.50 | 9.22 | 4.49 | 10.75 / 75.0 | 5.66 / 72.8 |
| dots.tts (MF, NFE=4) | 3.95 | 4.05 | 9.10 | 4.37 | 10.73 / 73.8 | 5.24 / 70.9 |
Win-rate judged head-to-head against gpt-4o-mini-tts by Gemini-2.5-Pro-0506 across six expressiveness-oriented scenarios. SCA takes the top Syntactic Complexity score in the table (65.7%) — above every closed-source system — and Pretrain posts the best Emotions score among open-source systems (72.7%).
| Model | Voice | WER↓ | Overall↑ | Emotions↑ | Paraling.↑ | Foreign↑ | C. Pron.↑ | Quest.↑ | Syntax↑ |
|---|---|---|---|---|---|---|---|---|---|
| Gemini-2.5-Flash-TTS* | Zephyr | 10.39 | 70.7% | 95.9% | 91.3% | 58.5% | 55.7% | 63.0% | 57.9% |
| Gemini-2.5-Pro-TTS* | Zephyr | 11.79 | 69.3% | 86.9% | 82.3% | 58.2% | 64.8% | 61.3% | 61.8% |
| gpt-4o-audio-preview* | Ballad | 11.87 | 65.2% | 88.8% | 82.1% | 60.2% | 40.4% | 57.0% | 59.5% |
| gpt-4o-mini-tts* | Alloy | 10.76 | 56.3% | 59.2% | 58.8% | 57.3% | 52.4% | 52.7% | 57.1% |
| baseline: gpt-4o-mini-tts | Alloy | 10.61 | 50.0% | — | — | — | — | — | — |
| dots.tts (Pretrain) | basic_ref_en | 10.86 | 49.2% | 72.7% | 54.7% | 39.5% | 18.0% | 48.4% | 58.4% |
| dots.tts (MF4) | basic_ref_en | 11.75 | 47.9% | 59.8% | 55.2% | 36.3% | 16.7% | 50.5% | 64.8% |
| dots.tts (SCA) | basic_ref_en | 10.45 | 47.6% | 63.9% | 52.7% | 39.4% | 16.4% | 47.0% | 65.7% |
| Qwen3-TTS | basic_ref_en | 17.32 | 42.8% | 39.8% | 50.7% | 25.4% | 30.0% | 48.9% | 60.4% |
| HumeAI* | — | 12.85 | 42.7% | 61.6% | 36.9% | 34.6% | 34.3% | 43.2% | 44.6% |
| Qwen3-TTS | Ryan | 19.65 | 42.3% | 60.5% | 62.7% | 17.1% | 9.8% | 56.4% | 43.0% |
| VoxCPM 2 | basic_ref_en | 11.84 | 41.1% | 42.3% | 44.1% | 33.3% | 18.6% | 53.4% | 52.3% |
| MiniMax/speech-02-hd* | EN-narr | 10.02 | 36.6% | 40.9% | 34.3% | 34.3% | 16.3% | 47.3% | 43.9% |
| 11Labs Multilingual v2* | Brian | 11.19 | 33.9% | 30.4% | 45.5% | 35.5% | 14.5% | 39.5% | 35.5% |
| F5-TTS | basic_ref_en | 16.47 | 15.3% | 26.8% | 21.6% | 1.8% | 1.4% | 14.8% | 23.8% |
* Closed-source / commercial. Table shows a selected subset for brevity — for the full leaderboard, see EmergentTTS-Eval-public.
Streaming-inference benchmarks under --optimize on a Seed-TTS-Eval mix (100 utterances across zh / en / zh-hard, first post-warmup request excluded, N=99 per group). voice_cloning uses reference audio + transcript; text_only uses text with no reference. Common config: precision=bfloat16, guidance_scale=1.2, seed=42; SOAR uses num_steps=10, MF uses num_steps=4. Hardware / stack: single H800, torch 2.8 + CUDA 12.8. The --optimize path also accelerates non-streaming generate() calls; numbers below are the streaming path.
Note:
--optimizetriggers a one-shottorch.compilewarmup that walks every DiT compile bucket + KvPrefill + vocoder chunk sizes. Cold start takes ~3 minutes on H800; every subsequent request runs at the steady-state RTF above. Passwarmup_on_optimize=FalsetoDotsTtsRuntimeif you want to skip warmup and accept the first request paying the compile cost.
| Group | audio mean (s) | latency p50 / p90 (s) | first-chunk p50 / p90 (ms) | RTF mean / p50 / p90 | peak alloc (GB) |
|---|---|---|---|---|---|
| SOAR / voice_cloning | 7.57 | 1.13 / 3.04 | 225 / 404 | 0.21 / 0.20 / 0.26 | 7.86 |
| SOAR / text_only | 7.78 | 0.95 / 3.02 | 69 / 79 | 0.18 / 0.18 / 0.20 | 7.85 |
| MF / voice_cloning | 7.46 | 0.88 / 1.73 | 204 / 381 | 0.16 / 0.15 / 0.21 | 5.74 |
| MF / text_only | 7.65 | 0.68 / 2.06 | 68 / 78 | 0.13 / 0.13 / 0.15 | 5.73 |
Bucket = total prompt + generated audio in latent patches (one patch ≈ 160 ms).
| Bucket | Total audio cap | SOAR / voice_cloning | SOAR / text_only | MF / voice_cloning | MF / text_only |
|---|---|---|---|---|---|
| <64 patches | <10.24s | 5.65 GB | 5.64 GB | 5.30 GB | 5.29 GB |
| <128 patches | <20.48s | 6.53 GB | 6.52 GB | 5.47 GB | 5.46 GB |
| <256 patches | <40.96s | 7.86 GB | 7.85 GB | 5.74 GB | 5.73 GB |
| <512 patches | <81.92s | 10.51 GB* | 10.51 GB* | 6.29 GB* | N/A** |
* From explicit long-audio probes (actual spans within 256–512 patches).
** mf / text_only did not reach the 256–512 bucket under either synthetic (x4) or real long-text probes; longest observed 237 patches at 5.73 GB.
Serving throughput on Seed-TTS-Eval EN against a single Omni server started from examples/configs/dots_tts.yaml (max_running_requests=16, bf16, num_steps=4, backbone decode CUDA graph + graph-captured acoustic tail). Each row is the mean of two runs, seed 42. Hardware: 1× H100. Full write-up: SGLang Omni cookbook — Performance.
| Concurrency | Throughput (req/s) | Mean latency | RTF (per-req) | audio_s/s | WER |
|---|---|---|---|---|---|
| 1 | 0.90 | 1.11 s | 0.284 | 3.58 | 1.06% |
| 2 | 1.48 | 1.35 s | 0.329 | 6.16 | 1.25% |
| 4 | 2.43 | 1.64 s | 0.399 | 10.14 | 1.36% |
| 8 | 3.99 | 2.00 s | 0.486 | 16.65 | 1.31% |
| 16 | 4.64 | 3.43 s | 0.830 | 19.36 | 1.31% |
| 32 | 4.43 | 7.15 s | 1.797 | 18.47 | 1.27% |
Zero failed requests in every run, and no sample above 50% WER. c=1 is a 50-sample latency probe; the other rows use the full 1,088-sample set. WER is measured with Qwen/Qwen3-ASR-1.7B on the first run of each row.
To reproduce (server already running as above):
python -m benchmarks.eval.benchmark_tts_seedtts \
--meta zhaochenyang20/seed-tts-eval-arrow \
--model dots-studio/dots.tts-mf \
--ref-format references \
--base-url http://127.0.0.1:8000 --port 8000 \
--lang en --max-concurrency 16 --warmup 8 --seed 42 \
--generate-only --use-existing-server \
--output-dir results/dots-seedtts-en-c16
python -m benchmarks.eval.benchmark_tts_seedtts \
--meta zhaochenyang20/seed-tts-eval-arrow \
--model dots-studio/dots.tts-mf \
--ref-format references --lang en --seed 42 \
--transcribe-only --port 8000 \
--output-dir results/dots-seedtts-en-c16Third-party ports and integrations of dots.tts, maintained by the community.
| Project | Description | Maintainer |
|---|---|---|
| sglang-omni | High-concurrency serving for dots.tts (cookbook) | @sgl-project |
| dots-tts-mlx | Pure-MLX inference port for Apple Silicon (Python) | @sb1992 |
| mlx-swift-dots-tts | Native MLX Swift port for Apple Silicon (no Python runtime) | @sammcj |
| Dots-TTS-ComfyUI | ComfyUI custom nodes for TTS, voice cloning, and Whisper transcription | @Saganaki22 |
- Misuse risk. High-fidelity zero-shot voice cloning can produce highly realistic synthetic speech. The released checkpoints are intended for research and authorized deployment. Do not use dots.tts for impersonation, fraud, or disinformation. Combine downstream use with consent-aware reference-audio policies, robust synthetic-speech detection, and content watermarking. Clearly mark AI-generated audio.
- Low-resource WER gap. A BPE backbone inherits the text LLM's language coverage at the cost of a higher data appetite. On script-divergent and under-represented languages (Arabic, Hindi, Turkish, Vietnamese) the WER gap visible on the MiniMax benchmark reflects this, and the same long tail surfaces on the Foreign Words and Complex Pronunciation scenarios of EmergentTTS-Eval. Speaker similarity is preserved across these languages.
- Speech-heavy training. Although the AudioVAE is trained at 48 kHz and is modality-agnostic in principle, the backbone is trained on a speech-heavy mixture. Singing and unified speech + sound generation are not covered in this release.
If you find dots.tts useful, please consider citing the technical report and starring the repository.
@article{dotstts2026,
title = {dots.tts Technical Report},
author = {dots.tts Team},
year = {2026},
eprint = {2606.07080},
archivePrefix = {arXiv},
primaryClass = {cs.SD},
}dots.tts code and released checkpoints are licensed under Apache-2.0.
