MOSS-TTS-Local-Transformer-v1.5 (GGUF)
Brought to you by the LocalAI team.
GGUF conversion of OpenMOSS-Team/MOSS-TTS-Local-Transformer-v1.5
for moss-tts.cpp: a C++17/ggml
inference port of the OpenMOSS MOSS-TTS family that runs entirely on stock ggml
with no Python, ONNX or torch at inference time.
Architecture
MossTTSLocal v1.5 is an RQ-Transformer text-to-speech model:
- Global backbone: a 36-layer Qwen3 transformer over time (the text + speech prefix), hidden size 2560.
- Local depth transformer: a 1-layer GPT-J block (LayerNorm, fused QKV, interleaved RoPE, SiLU MLP) over the codebooks within each frame.
- Binary decision head: a direct 2-wide
local_text_headon channel 0 that chooses continue (audio slot) vs stop (audio end) per frame. - 12 RVQ codebooks decoded through MOSS-Audio-Tokenizer-v2 at 48 kHz stereo (interleaved output).
The non-matmul tensors (all lc.* heads and embeddings, every norm and bias)
are kept in f32 in every quant; only the Qwen3 global and GPT-J local
attention/FFN matmuls are quantized, so the CPU gather/head paths stay exact.
Verification
This port is numerically verified against the reference PyTorch implementation: the language model matches to about 1e-5 with an exact greedy code sequence, and the MOSS-Audio-Tokenizer-v2 decode matches at about 115 dB SNR (bit-exact in f32). On CPU it runs roughly twice as fast per frame as the reference PyTorch at the same f32 precision.
Files
| quant | size | notes |
|---|---|---|
| f16 | 9.4 GB | half precision, code-exact vs f32 |
| q8_0 | 6.0 GB | 8-bit, near-lossless, recommended default |
The non-matmul path (heads, embeddings, norms, biases) stays f32 in both quants.
This repo also ships the codec (moss-audio-tokenizer-v2-f32) and tokenizer
(moss-tokenizer-v1_5) GGUFs required to run the model.
Usage
With moss-tts.cpp built:
moss-tts-cli tts-local \
--model moss-tts-local-v1_5-q8_0.gguf \
--codec moss-audio-tokenizer-v2-f32.gguf \
--tokenizer moss-tokenizer-v1_5.gguf \
--text "Hello from the LocalAI team." \
--out out.wav
The output is a 48 kHz stereo WAV. Swap --model for any of the quants above.
Links
- Inference engine: https://github.com/mudler/moss-tts.cpp
- Base model: https://huggingface.co/OpenMOSS-Team/MOSS-TTS-Local-Transformer-v1.5
- Codec: https://huggingface.co/OpenMOSS-Team/MOSS-Audio-Tokenizer-v2
License
Released under the Apache-2.0 license, following the upstream base model.