Higgs Audio v3 TTS is built for voice chat: it speaks, not just reads. It turns model responses into expressive conversational speech across 100+ languages, with zero-shot voice cloning and inline control over emotion, style, prosody, pauses, and sound effects.
[!TIP]
Released for research and non-commercial use under the Boson Higgs Audio v3 Research and Non-Commercial License. Production, hosted APIs, or revenue-generating use requires a separate commercial license. Prohibited: voice cloning without consent, impersonation, fraud, election deception, biometric surveillance, or any unlawful use.
Higgs Audio v3 TTS Architecture
Higgs autoregressive decoder consumes interleaved text and audio tokens. Audio is encoded by the Higgs Tokenizer into 8 codebooks at 25 fps, staggered via a delay pattern, then mapped to backbone hidden states through a multi-codebook fused embedding. Output codes pass through a multi-codebook fused head, are de-delayed, and decoded back to waveform.
We evaluate Higgs Audio v3 TTS on public multilingual TTS suites and our internal 111-language Higgs-Multilingual set, covering both common and lower-resource languages.
WER / CER (↓, ×100) macro-averaged across each benchmark's language set. Lower is better; bold marks the best per row. All numbers are reproducible end-to-end with original metrics and normalization.
Benchmark
Higgs Audio v2
Higgs Audio v3
Fish Audio S2 Pro
Qwen3-TTS-1.7B
VibeVoice-7B
IndexTTS-2
MiMo-Audio-7B-Instruct
MOSS-TTS-v1.5
OmniVoice
ChatterBox
FireRedTTS-2
SeedTTS
2.10
1.11
1.31
1.30
3.59
1.63
3.70
1.73
1.21
17.00
1.72
CV3
21.19
4.41
4.60
7.73
11.66
129.26
71.55
6.11
4.92
32.62
19.20
MiniMax-Multilingual
49.86
2.74
5.15
27.41
8.21
112.91
85.67
3.78
2.98
49.30
12.52
Higgs-Multilingual
52.24
3.61
8.68
97.09
13.74
57.71
59.61
21.28
3.63
57.52
33.69
Emergent TTS
Win-rate (↑) per category — judge preference vs the BASELINE row; bold marks the highest win-rate per column. For a fair comparison, every model shares the same reference audio per prompt, and we run the benchmark text verbatim — no inline control tags inserted.
Model
Overall ↑
Emotions ↑
Foreign Words ↑
Paralinguistics ↑
Complex Pronunciation ↑
Questions ↑
Syntactic Complexity ↑
Higgs Audio v3
53.65%
53.75%
48.75%
68.57%
25.10%
61.43%
60.71%
Fish Audio S2 Pro
43.80%
53.04%
33.93%
53.75%
18.16%
55.00%
45.71%
Qwen3-TTS-1.7B
38.84%
45.54%
24.64%
44.29%
30.00%
53.39%
34.11%
IndexTTS-2
31.12%
39.29%
5.36%
42.50%
12.45%
45.89%
38.93%
MOSS-TTS-v1.5
43.89%
60.54%
35.18%
51.43%
11.63%
53.21%
47.32%
OmniVoice
40.82%
61.07%
28.75%
52.68%
13.67%
45.00%
40.36%
Usage
SGLang Usage
Pair the weights in this repo with SGLang-Omni — a production serving stack with continuous batching for multi-codebook decoding and the same inline tag controls. The Higgs TTS cookbook walks you through installation, server launch, request examples, and the full API reference.
1curl -X POST http://localhost:8000/v1/audio/speech \2 -H "Content-Type: application/json"\3 -d '{"input": "Hello, how are you?"}'\4 --output output.wav
Voice cloning
Supplying the reference transcript (text) materially improves cloning fidelity.
python
1import requests
23resp = requests.post(4"http://localhost:8000/v1/audio/speech",5 json={6"input":"Have a nice day and enjoy south california sunshine.",7"references":[{8"audio_path":"ref.wav",9"text":"Hey, Adam here. Let's create something that feels real, sounds human, and connects every time.",10}],11"temperature":0.8,"top_k":50,"max_new_tokens":1024,12},13)14withopen("output.wav","wb")as f:15 f.write(resp.content)
Streaming (Server-Sent Events)
Set "stream": true to receive base64-encoded WAV chunks as the vocoder emits them — sub-second time-to-first-audio. Each event carries audio.data (base64 WAV bytes); the terminal event has finish_reason: "stop" plus usage metadata.
python
1import requests, base64, json
23with requests.post(4"http://localhost:8000/v1/audio/speech",5 json={"input":"Get the trust fund to the bank early.","stream":True},6 stream=True,7)as resp,open("output.wav","wb")as f:8for line in resp.iter_lines():9ifnot line ornot line.startswith(b"data: ")or line ==b"data: [DONE]":10continue11 event = json.loads(line[6:])12if event.get("finish_reason")=="stop":13break14 audio = event.get("audio")or{}15if audio.get("data"):16 f.write(base64.b64decode(audio["data"]))
Inline control tokens
Embed <|emotion:…|>, <|style:…|>, <|prosody:…|>, and <|sfx:…|> tokens directly in input. Two rules:
Delivery tokens first. Emotion, style, and the prosody speed / pitch / expressive tokens shape the whole turn — put them at the start of input. Positional tokens (<|prosody:pause|>, <|prosody:long_pause|>, <|sfx:…|>) go inline exactly where they fire.
Pair every <|sfx:…|> with its onomatopoeia. E.g. <|sfx:laughter|>Haha, <|sfx:sigh|>Uh, <|sfx:sneeze|>Achoo. The written sound gives the model the acoustic cue to realize the effect.
Example — amusement + laughter:
bash
1curl -X POST http://localhost:8000/v1/audio/speech \2 -H "Content-Type: application/json"\3 -d '{"input": "<|emotion:amusement|><|prosody:expressive_high|>Wait, wait, that was kind of hilarious. <|sfx:laughter|>Hehe, no, seriously, I was not ready for that."}'\4 --output output.wav
Throughput
Throughput on Seed-TTS EN (full set, N=1088 per run). Client --max-concurrency sweep against a Higgs server (max_running_requests=16, bf16, CUDA Graph on). Each row is the mean of 3 runs. Hardware: 1× H100.
Concurrency
Throughput (req/s)
Mean latency
RTF (per-req)
audio_s/s
1
1.62
617 ms
0.147
6.89
2
2.70
742 ms
0.180
11.37
4
5.45
733 ms
0.177
22.84
8
8.91
898 ms
0.217
37.38
16
14.74
1079 ms
0.262
61.84
Concurrency — Maximum number of in-flight client requests (--max-concurrency).
Throughput (req/s) — Completed requests divided by total benchmark wall-clock time.
Mean latency — Average end-to-end time per request (send to full response received).
RTF (per-req) — Average ratio of processing time to generated audio duration per request (<1 is faster than real time).
audio_s/s — Total seconds of audio produced divided by total benchmark wall-clock time.
To reproduce the results, follow the instructions in this script.