bilibili · Voice

IndexTTS2.5

Commercial use: conditions applybilibili Model Use License Agreement

The successor to IndexTTS2, with an unambiguous licence. The cap is Llama-style: written authorisation is needed only if you exceeded 100 million monthly active users in the preceding month or a billion RMB in annual revenue. The card states that the model does not check whether the speaker in your reference clip consented, and that getting that consent is your job.

IndexTeam/IndexTTS-2.5 on Hugging Face audio.cpp

The licence

Summarized from the linked source documents, last checked 25 August 2026. Every claim links to its source; anything unconfirmed is marked unconfirmed.

bilibili Model Use License Agreement

Commercial use: conditions apply

Commercial use is permitted with a scale cap and some housekeeping. Separate written authorisation is required only above 100 million monthly active users in the preceding calendar month or RMB 1 billion in annual revenue.

Conditions

Written authorisation required above 100M MAU in the preceding calendar month, or RMB 1bn annual revenue.
Retain copyright notices and a copy of the licence, and bind downstream recipients to the same terms.
State that your modifications are not endorsed by the rights-holder.
You are responsible for obtaining rights to any third-party data or weights you combine with it.
You may not use the model to improve other AI models, except IndexTTS2 itself or non-commercial models.

What about the audio you generate?

The model and its outputs are provided "as is" with no warranty. Prohibited output includes anything unlawful, false information, and discriminatory or privacy-infringing content; high-risk deployment (medical, autonomous driving, military, critical infrastructure) puts regulatory compliance on you. The model card is explicit that it does not verify a reference speaker's consent and that obtaining it is the user's responsibility.

Correction to the shipped catalog: The shipped catalog says "Unknown". It is the bilibili Model Use License Agreement, and its text has been reviewed.

Based on the licence text as of the date below. Licences change; the links carry the authoritative version.

Specs

Transcribed from the shipped catalog, audiocpp_models_catalog.json — that file is authoritative if a number here disagrees with it.

Vendor: bilibili
Catalog id: audiocpp-index-tts2-5
audio.cpp loader family: index_tts2
Can do: Text to speech
Weights repo: audio-cpp/audio.cpp-gguf
Weights file: IndexTTS2.5-GGUF/index-tts2_5-q8_0.gguf
Account needed to download: No
Max clip length: 60s
Sample rate: 44.1kHz mono
Approx. VRAM: 4.2 GB
In the picker by default: No — opt in from Settings
Run end-to-end here: No — catalogued, not tested here

Getting it

There is no per-model install. One native binary runs all of these, so getting a model is a download of its weights and nothing else — no virtualenv, no torch pin, no CUDA wheel to match against your driver.

From the CLI

soundbox model install audiocpp
soundbox pull audiocpp-index-tts2-5

The binary is fetched from audio.cpp's GitHub releases the first time you ask for it and cached under your own data directory. Soundbox ships no native binaries and vendors none.
Weights land in <models dir>/audiocpp/audiocpp-index-tts2-5/ rather than in the shared Hugging Face cache, so a download stays scoped to the model you asked for.
This one is opt-in: switch it on in the Models page's “Enable more models” section before it appears in the picker.

Worth knowing

Opt-in and untested here.

Sources

Primary sources: the model's own repository, the project it came from, and the conversion audio.cpp actually downloads. Never invented — an entry with nothing findable says so instead.

Licence details on these pages are summaries of the linked source documents, last checked 25 August 2026. They are not legal advice, and Soundbox is not affiliated with any model's authors — weights download from Hugging Face under the user's own account and terms. Company and model names identify whose work it is, and belong to their owners. The linked licence text is authoritative; commercial use should be checked against it, per model, before anything ships.

Same loader family (index_tts2)

IndexTTS2