Audio8 TTS Preview is a compact multilingual text-to-speech model with
zero-shot voice cloning. This repository provides its CPU-oriented ONNX
deployment: INT8 per-token DualAR models, an FP16 neural audio codec, the
tokenizer, the packaged reference voice, and the optional FP16 encoder used to
register reference voices.
Model files only. Inference, streaming service, and voice-registration
code live in the dedicated
0.1B INT8 ONNX Runtime.
The older onnx_runtime/ directory targets the incompatible 0.6B INT4
graphs and must not be used with this model.
Acknowledgments
The per-token ONNX export design (stacked recurrent interface, valid-prefix
attention) and the INT8 quantization strategy in this repository were
adapted from the community conversion
Masterx/Audio8-TTS-Preview-0.1B-ONNX-INT8.
The graphs and tooling are independently produced by the Audio8 team from
the official checkpoint and do not reuse that repository's artifacts.
Thanks to Masterx and the community for exploring ONNX Runtime conversion of
the 0.1B model.
Why this ONNX release
Deployment characteristic
CPU native
ONNX Runtime CPUExecutionProvider; no CUDA requirement
Small runtime
No PyTorch, Transformers, or Hugging Face Hub dependency after download
Low memory
About 0.6 GB after loading the online sessions in our test configuration
Voice cloning
Bundled FP16 codec encoder for reusable local voice profiles
Local service
CLI, web UI, HTTP API, streaming PCM, and OpenAI-compatible endpoint
The slow AR runs as a per-token recurrent graph (attention + Mamba states
passed explicitly) so the CPU workload stays tiny: about 19 ms per slow-AR
token and 8 ms per fast-AR frame on our test host (8 threads). A one-time
prompt prefill costs about 19 ms per prompt token. Normal synthesis loads only
the Slow AR, Fast AR, and codec decoder sessions; the online model files
occupy about 0.6 GB. The complete repository, including the voice-registration
encoder, is about 1.0 GB. Actual memory use varies by platform and allocator
behavior.
Supported Languages
Cantonese ·
Chinese ·
Dutch ·
English French ·
German ·
Italian ·
Japanese Korean ·
Polish ·
Spanish
Preview status: Language coverage is intentionally limited in this
release. For the best results, use one of the 11 recommended languages
above. Broader multilingual coverage and Chinese dialect support are
planned for future releases.
Model Details
Audio8 TTS uses a DualAR architecture inspired by
Fish Audio S2 Pro. The 0.1B model
uses a Falcon-H1 hybrid slow AR (attention + Mamba) that predicts one semantic
token per audio frame; the fast AR predicts the frame's codec codebooks,
conditioned on the slow hidden state and preceding codebooks.
44.1 kHz, 2,048 samples per model frame (~21.5 frames/s)
Context
Up to 2,048 packed text/audio positions
Execution provider
ONNX Runtime CPU
Quick Start
Python 3.10 or newer is required. The runtime uses ONNX Runtime's
CPUExecutionProvider; platform-specific ONNX Runtime wheels may be needed on
devices such as Jetson. The current release is tested on macOS arm64 and Linux
x86_64.
The model files are stored at this Hugging Face repository's root. Downloading
with --local-dir model creates the exact layout expected by the runtime:
The command writes outputs/example.wav and [10, T] codec codes to
outputs/example.npy.
3. Register a reference voice
Start the local service and open http://127.0.0.1:8024. The page provides text
generation, voice selection, WAV playback/download, reference-voice
registration, memory status, and runtime reload. The Swagger API documentation
is available at http://127.0.0.1:8024/docs. Upload a 0.5-30 second reference
recording, its exact transcript, and a voice name to register a new voice.
bash start_server.sh
The same operation is available through HTTP:
bash
1curl http://127.0.0.1:8024/api/voices/register \2 -F 'audio=@/absolute/path/reference.wav'\3 -F 'text=The exact transcript of the reference recording.'\4 -F 'name=speaker_a'\5 -F 'overwrite=false'
See the complete
0.1B ONNX Runtime guide
for streaming output, configuration, memory management, and service controls.
Evaluation
The source Audio8 TTS Preview 0.1B checkpoint is a compact multilingual model;
see the
base model card for
details.
INT8 quantization can change sampled token sequences, so quality should be
evaluated for each target language, voice, and deployment setting rather than
assuming bit-for-bit equivalence with the source checkpoint. This repository
contains the 0.1B INT8 graphs; use the dedicated runtime linked above when
running them.
Limitations and Responsible Use
This is a Preview checkpoint with limited multilingual and dialect coverage.
Very long, noisy, or incorrectly transcribed references can reduce stability
and speaker similarity.
Generated speech can be misused for impersonation or misinformation. Obtain
consent before cloning a voice and clearly disclose synthetic audio where
appropriate.
Evaluate the model for accuracy, safety, and legal compliance before
deployment.
License and Acknowledgements
The code and model weights are released under the
Apache License 2.0.
See the upstream
NOTICE for
attribution details.
We thank the Fish Audio team for publishing the DualAR architecture used in
Fish Audio S2 Pro.