Nabra-82M-v0.1

Nabra-82M — Arabic Text-to-Speech

Nabra is an 82M-parameter neural text-to-speech model for Modern Standard Arabic (MSA). It is a fine-tune of Kokoro-82M (a StyleTTS2 / ISTFTNet architecture), adapted to Arabic phonetics with a dedicated pharyngeal-consonant vocabulary and an Arabic grapheme-to-phoneme front-end. It ships a single, natural female voice — af_msa.

⚠️ Nabra expects diacritized (tashkeel'd) input. Arabic drops short vowels in normal writing; without them the phonemizer guesses badly. Run text through a diacritizer first (see G2P pipeline).

Highlights

• 🗣️ Natural MSA speech at 24 kHz from a compact 82M model.
• 🔤 Arabic-aware phonemes — the pharyngeal fricatives ع (ʕ) and ح (ħ) get dedicated embedding slots (Kokoro vocab ids 7 & 8), preserving the ع/ء and ح/ه contrasts that generic phonemizers collapse.
• 📱 Runs on-device — an MLX conversion (oddadmix/Nabra-82M-MLX) runs fully offline on Apple Silicon / iOS via kokoro-ios.
• ⚡ Real-time factor < 1 on CPU for typical sentences.

Intended Use

• Arabic voice assistants, screen readers, and accessibility tools
• Audiobook / e-learning narration in MSA
• Voice output for on-device Arabic LLM pipelines (STT → LLM → diacritize → Nabra)

Out of scope: dialectal Arabic (trained on MSA), singing, non-Arabic text, and speaker cloning (single fixed voice).

Usage

Nabra runs through the Kokoro pipeline with an Arabic front-end: normalize → diacritize (camel-tools) → phonemize (espeak-ng) → synthesize.

# Install Kokoro from the Nabra fork — it carries the Arabic config/vocab
pip install "kokoro @ git+https://github.com/Oddadmix/kokoro.git@main"
pip install torch soundfile huggingface_hub misaki camel-tools
# one-time: fetch the MSA diacritizer model (not shipped in the pip package)
camel_data -i disambig-mle-calima-msa-r13
# grab the Arabic G2P front-end
wget https://gist.githubusercontent.com/Oddadmix/dc699f7942a9516ce29d4842c7aed756/raw/827b541c892a862f9ef3b44006a6e27b100d1bdd/arabic_g2p.py

import numpy as np, torch, soundfile as sf
from huggingface_hub import hf_hub_download, list_repo_files
from arabic_g2p import ArabicG2P, EXTRA_SYMBOLS, clean_phonemes, normalize_text
from kokoro import KModel, KPipeline
from kokoro import pipeline as kpipeline_mod

REPO_ID = "oddadmix/Nabra-82M-v0.1"
files = list_repo_files(REPO_ID)
model_file = next(f for f in files if f.endswith(".pth"))   # fine-tuned weights
voice_file = next(f for f in files if f.endswith(".pt"))    # af_msa voicepack
config     = hf_hub_download(REPO_ID, "config.json")
model_path = hf_hub_download(REPO_ID, model_file)
voice_path = hf_hub_download(REPO_ID, voice_file)

# Load OUR fine-tuned weights (config + model given → base model is never fetched).
# disable_complex=True uses the real-valued STFT (robust on all GPUs).
kmodel = KModel(repo_id=REPO_ID, config=config, model=model_path,
                disable_complex=True).eval()
kmodel.vocab.update(EXTRA_SYMBOLS)                          # ʕ→7, ħ→8

# Route the Kokoro pipeline through espeak-ng Arabic + phoneme cleanup
kpipeline_mod.LANG_CODES.setdefault("ar", "ar")
pipeline = KPipeline(lang_code="ar", repo_id=REPO_ID, model=kmodel)
_orig_g2p = pipeline.g2p
pipeline.g2p = lambda t: (clean_phonemes(_orig_g2p(t)[0]), _orig_g2p(t)[1])

voice = torch.load(voice_path, map_location="cpu", weights_only=True)
g2p = ArabicG2P(diacritize=True)                           # camel-tools MLE

# ── Synthesize ────────────────────────────────────────────────────────────────
text = "مرحبا بك في نبرة"                                  # raw MSA (tashkeel optional)
text_norm, _ = normalize_text(text)
diac = g2p.diacritize(text_norm)                           # → مَرْحَبًا بِكَ فِي نَبْرَة

audios = [audio for _, _, audio in pipeline(diac, voice=voice, speed=1.0)]
wav = np.concatenate([a.detach().cpu().numpy() for a in audios]).astype(np.float32)
sf.write("nabra.wav", wav, 24000)

Already diacritized? Skip step 2 — pass your tashkeel'd text straight to the pipeline (pipeline(text, voice=voice)), or build ArabicG2P(diacritize=False).

• 🎮 Try it in the browser: Nabra-82M Demo Space
• 📱 On-device (iOS / MLX): oddadmix/Nabra-82M-MLX + kokoro-ios (bundles neural diacritization, no camel-tools needed)

G2P Pipeline

Text is converted to phonemes in four stages so training and inference use an identical symbol set:

1. Normalize — strip citation markers and Latin-script loanwords, tidy whitespace.
2. Diacritize — restore MSA short vowels with camel-tools MLE (calima-msa-r13). Skipped if the text is already diacritized. For a fully neural, on-device alternative, use CATT.
3. Phonemize — espeak-ng Arabic (ar) → IPA.
4. Clean — strip espeak's mid-word syllable dots (which would inject phantom pauses) and pharyngealization/bracket markers; keep ʕ/ħ.

Model Details

Files & Formats

• This repo (Nabra-82M-v0.1, PyTorch/KModel): kokoro_arabic.pth, af_msa.pt, config.json
• MLX (Nabra-82M-MLX): kokoro-v1_0.safetensors, af_msa.safetensors, config.json

Limitations & Notes

• Requires diacritized input for correct pronunciation.
• MSA only — not trained for Egyptian or other dialects.
• Single voice (af_msa); additional voices need more voicepacks.

Related

• 🧩 kokoro-ios — MLX Swift inference (TTS + on-device Arabic diacritization)
• 🍴 Oddadmix/kokoro — Kokoro fork with the Arabic config/vocab
• 📜 kikiri-tts — upstream Kokoro/StyleTTS2 fine-tuning recipe
• 🔤 CATT — Arabic diacritization (Apache-2.0)

Citation

@misc{nabra2026,
  title  = {Nabra-82M: Modern Standard Arabic Text-to-Speech},
  author = {oddadmix},
  year   = {2026},
  howpublished = {\url{https://huggingface.co/oddadmix/Nabra-82M-v0.1}}
}

License & Attribution

Released under Apache-2.0, following Kokoro-82M (Apache-2.0) and StyleTTS2 (MIT). Arabic diacritization in the pipeline uses camel-tools and/or CATT (Apache-2.0).

The fine-tuning recipe is built on kikiri-tts by @semidark — the upstream Kokoro/StyleTTS2 training workflow this Arabic adaptation extends.