Files
esh-pfi-infrastructure/stacks/voxtral
vh e0d1c44137 chore(fleet): repoint stale irv-ml1 refs (10.100.79.3 -> irv-ml1.nh3.internal)
The 2026-09-06 headscale cutover retired irv-ml1's wg0 tunnel IP 10.100.79.3
(now 10.6.110.50). Repointed all LIVE canonical refs to the DNS NAME so the next
move can't re-break them: homepage.href/siteMonitor labels across 25 stack
composes, load-bearing env defaults (asset-engine INFERENCE_HOST, open-webui
AUDIO_TTS_OPENAI_API_BASE_URL, skaldsong SKALDSONG_TTS_BASE_URL, zonos-gateway
ZONOS_URL, dia), homepage services.yaml manual cards (Voice Design Studio,
IRV-ML1), and servers/irv-ml1/ssh-target. Updated the stale 'WG tunnel' comment
to the mesh reality.

Left as-is: README curl-examples and .env.example comments (docs), and historical
mentions in CLAUDE.md/persistent-memory. NOTE: applying the label repoints to the
RUNNING irv-ml1 containers needs a recreate per service (labels read at creation);
deployed .env values are separate from these canonical defaults.
2026-09-07 15:08:56 -07:00
..

Voxtral TTS

mistralai/Voxtral-4B-TTS-2603 — Mistral AI's 4B open-weight streaming TTS, served via the vLLM-Omni production serving stack (Mistral co-developed). Released March 28, 2026.

⚠️ License

CC BY-NC. Personal use, research, and internal tooling are fine. Don't ship Voxtral output in any commercial product without re-licensing from Mistral. The other TTS in this fleet (Kokoro, Chatterbox, Fish S2-Pro, IndexTTS-2, Qwen3-TTS, CosyVoice) are all open-licensed and clean for commercial work.

Why this stack exists

Multilingual streaming with serious speed:

use case
Voxtral multilingual EN/FR/DE/ES/IT/PT/NL/HI streaming, 70 ms model latency
Kokoro low-latency English, fixed voice library
Chatterbox Turbo low-latency English w/ cloning + 9 paralinguistic tags
Fish Audio S2-Pro richest paralinguistic English (15k+ tags)
IndexTTS-2 English voice cloning + emotion vector / text control
Qwen3-TTS-1.7B English voice cloning (slow on official backend)
CosyVoice 3 multilingual (Chinese-leaning)
VibeVoice 1.5B long-form / multi-speaker dialogue

Voxtral fills the multilingual + low-latency + cloning slot that's been weak in the fleet (CosyVoice is multilingual but slow on English; nothing else is multilingual at all).

Headline numbers

  • 70 ms model latency for a typical 10 s sample (500-char input)
  • 9.7× realtime factor
  • 68.4% blind A/B win rate vs ElevenLabs Flash v2.5 in voice cloning evaluations
  • 8 languages: EN, FR, DE, ES, IT, PT, NL, HI

API

vLLM-Omni serves an OpenAI-compatible API at http://10.100.79.3:8201/v1:

# Single-shot synthesis.
curl -fsS -X POST http://10.100.79.3:8201/v1/audio/speech \
  -H 'Content-Type: application/json' \
  -d '{"model":"mistralai/Voxtral-4B-TTS-2603","input":"Hello there.","voice":"alloy","response_format":"wav"}' \
  > out.wav

# Streaming.
curl -fsS -X POST http://10.100.79.3:8201/v1/audio/speech \
  -H 'Content-Type: application/json' \
  -d '{"model":"mistralai/Voxtral-4B-TTS-2603","input":"long passage…","voice":"alloy","stream":true}' \
  | mpv --no-cache -

# vLLM-Omni standard endpoints.
curl http://10.100.79.3:8201/v1/models    # confirms model loaded
curl http://10.100.79.3:8201/v1/audio/voices  # built-in + cloned voices

Deploy

scripts/elway irv-ml1 --playbook playbooks/deploy-voxtral.yaml

First boot pulls Voxtral-4B (~8 GB BF16) into the HF cache + warms vLLM. Both are cached afterwards.

Hardware footprint

  • VRAM: ~16 GB practical (8 GB weights + KV + activation). Pinned to GPU 1 (RTX A6000) by default — comfortable headroom. The 3090's 24 GB CAN fit but it's tight for long streaming sessions.
  • Disk: ~8 GB for the Voxtral checkpoint + HF cache.

Voice library

Drop reference WAV / FLAC into /worktank/voxtral/voices/ on the host. The wrapper scans on request — no restart needed.