From: unsloth <huggingface.co/unsloth>Newsgroups: alt.freeweights.speechSubject:

csm-1b

Date: 2026-11-15Commit: 39e8c75Signed: 2DC28CC7B26A283B ✓

Text to speech model with 1.6B parameters. Safetensors weights, 4.17 GB in all. Published by unsloth under Apache-2.0.

1.6B params4.17GBcsm-1bsafetensorspermissive
FactsParams1.6BSize4.17 GBFormatssafetensorsTasktext to speechLicenseApache-2.0From sourcepermissive
$ fw get unsloth/csm-1b
# manifest sha256 082dd4aeb43a… · 4.17 GB · 10 files
$ fw verify ./csm-1b unsloth/csm-1b
From sourceHosted (signed)unsloth/csm-1bLast check: 2026-11-15 02:46 UTC

Get help: custom fine-tune or private deploy. We review your setup before we quote.

Works with

Overview

Size
4.17 GB
Weights
4.15 GB (safetensors)
Parameters
1.6B
Formats
safetensors
Task
text to speech
License
Apache-2.0 (permissive)
Files
10, each with a sha256
Publisher
unsloth
Added
2026-11-15
Section
alt.freeweights.speech
Lineage

Original release from the publisher.

Base model: sesame/csm-1b

Where these bytes come from
Publisher at the pinned commit→You

Sources are tried in order. A file counts only when its size and sha256 match the manifest. Sources are checked when you ask for them, not on a timer.

Sources
BadgeHostLast checkResult
From sourcehuggingface.co2026-11-15 02:46 UTCpassed

Model card

From the publisher at commit 39e8c75. Shown as plain text with links; images open at the publisher.

See our collection for all our TTS model uploads.

Learn to fine-tune TTS models - Read our Guide.

Unsloth Dynamic 2.0 achieves superior accuracy & outperforms other leading quants.

https://github.com/unslothai/unsloth/ https://discord.gg/unsloth https://docs.unsloth.ai/basics/text-to-speech-tts-fine-tuning

✨ Run & Fine-tune TTS models with Unsloth!#

Unsloth supportsFree NotebooksPerformanceMemory use
Sesame-CSM-1B▶️ Start on Colab-TTS.ipynb)1.5x faster58% less
Whisper Large V3▶️ Start on Colab1.5x faster50% less
Qwen3 (14B)▶️ Start on Colab2x faster70% less
Llama 3.2 Vision (11B)▶️ Start on Colab-Vision.ipynb)1.8x faster50% less

CSM 1B#

2025/03/13 - We are releasing the 1B CSM variant. Code is available on GitHub: SesameAILabs/csm.


CSM (Conversational Speech Model) is a speech generation model from Sesame that generates RVQ audio codes from text and audio inputs. The model architecture employs a Llama backbone and a smaller audio decoder that produces Mimi audio codes.

A fine-tuned variant of CSM powers the interactive voice demo shown in our blog post.

A hosted HuggingFace space is also available for testing audio generation.

Usage#

Setup the repo

git clone git@github.com:SesameAILabs/csm.git
cd csm
python3.10 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

# You will need access to sesame/csm-1b and meta-llama/Llama-3.2-1B
huggingface-cli login

Generate a sentence

from generator import load_csm_1b
import torchaudio

generator = load_csm_1b(device="cuda")

audio = generator.generate(
    text="Hello from Sesame.",
    speaker=0,
    context=[],
    max_audio_length_ms=10_000,
)

torchaudio.save("audio.wav", audio.unsqueeze(0).cpu(), generator.sample_rate)

CSM sounds best when provided with context. You can prompt or provide context to the model using a Segment for each speaker utterance.

speakers = [0, 1, 0, 0]
transcripts = [
    "Hey how are you doing.",
    "Pretty good, pretty good.",
    "I'm great.",
    "So happy to be speaking to you.",
]
audio_paths = [
    "utterance_0.wav",
    "utterance_1.wav",
    "utterance_2.wav",
    "utterance_3.wav",
]

def load_audio(audio_path):
    audio_tensor, sample_rate = torchaudio.load(audio_path)
    audio_tensor = torchaudio.functional.resample(
        audio_tensor.squeeze(0), orig_freq=sample_rate, new_freq=generator.sample_rate
    )
    return audio_tensor

segments = [
    Segment(text=transcript, speaker=speaker, audio=load_audio(audio_path))
    for transcript, speaker, audio_path in zip(transcripts, speakers, audio_paths)
]
audio = generator.generate(
    text="Me too, this is some cool stuff huh?",
    speaker=1,
    context=segments,
    max_audio_length_ms=10_000,
)

torchaudio.save("audio.wav", audio.unsqueeze(0).cpu(), generator.sample_rate)

FAQ#

Does this model come with any voices?

The model open sourced here is a base generation model. It is capable of producing a variety of voices, but it has not been fine-tuned on any specific voice.

Can I converse with the model?

CSM is trained to be an audio generation model and not a general purpose multimodal LLM. It cannot generate text. We suggest using a separate LLM for text generation.

Does it support other languages?

The model has some capacity for non-English languages due to data contamination in the training data, but it likely won't do well.

Misuse and abuse ⚠️#

This project provides a high-quality speech generation model for research and educational purposes. While we encourage responsible and ethical use, we explicitly prohibit the following:

  • Impersonation or Fraud: Do not use this model to generate speech that mimics real individuals without their explicit consent.
  • Misinformation or Deception: Do not use this model to create deceptive or misleading content, such as fake news or fraudulent calls.
  • Illegal or Harmful Activities: Do not use this model for any illegal, harmful, or malicious purposes.

By using this model, you agree to comply with all applicable laws and ethical guidelines. We are not responsible for any misuse, and we strongly condemn unethical applications of this technology.

Authors Johan Schalkwyk, Ankit Kumar, Dan Lyth, Sefik Emre Eskimez, Zack Hodari, Cinjon Resnick, Ramon Sanabria, Raven Jiang, and the Sesame team.

Files

10 files · 4.17 GBWeights 4.15 GB (safetensors). Sizes and sha256 from the signed manifest.
Hide all 10 files with their sha256
FileSizesha256
.gitattributes1.57 KB34448b82c17d60fec9b65b1f093c115ddbaadc04beb1b0140b6bfed2e012a930
README.md6.86 KBed0190855a95b424c08e2b4eaa5b4ea0f58139489f0a00de3febcaf97b1ef9f8
chat_template.jinja2.00 KBb43753fbbc23be93160cccf825d2cf97dec39538cb274350216940e7acbc0fe7
config.json3.12 KB497208badddb751a2e0c2b2ebf1e7fd6f96e7dba200f54347b3ec52e2e52b0f1
generation_config.json264 B7e8155f5846542bb15f8910a8dff0724d2961b28f10e4d98c58327825239b452
model.safetensors4.15 GB1c81da3653c0177283d17d0a94e8136e76429fcabed60ed336cea6abea6e81c3
preprocessor_config.json271 B8648040cda0469976874c733acbec88c0ef094cd95628ab63b32950f01872af9
special_tokens_map.json449 B03d62862d41de30db9e05cb4865de4f36c48ab3032327139fcdfacc5798a4828
tokenizer.json17.2 MB80f511469b4aceda8c17ccafef2310eceeda9dd4589cf2c062bd0279eef5646d
tokenizer_config.json50.6 KB250bef77ad6788610c416ccf4e0f6466607a12c0dc3156cca1031c2269170311
VersionsEach time the pinned upstream commit or file list changed in this repo. Newest first.
Upstream commitDateContents
39e8c756be pinned now2026-11-15 02:46 UTC10 files · 4.17 GB

Use it

$ fw get unsloth/csm-1b
# manifest sha256 082dd4aeb43a… · 4.17 GB · 10 files
$ fw verify ./csm-1b unsloth/csm-1b
fw.pyChecks the signature and every sha256, tries each source in order, resumes.
$ python3 fw.py get https://freeweights.allternit.com/manifests/unsloth/csm-1b.json --dir ./csm-1b $ python3 fw.py verify ./csm-1b ./unsloth__csm-1b.json
hfThe Hugging Face CLI with one setting. Same repo id.
$ HF_ENDPOINT=https://freeweights.allternit.com hf download unsloth/csm-1b --revision 39e8c756bec133ad7eb9ea1097c84a2bd891c949 --local-dir ./csm-1b

License

Name
Apache License 2.0
Id
Apache-2.0
Class
Permissive
Redistribution
yes
Listing
Hosted (signed)
Decided
License as declared by the publisher. No person read it. 2026-11-15
Text in
README.md
Text sha256
ed0190855a95b424c08e2b4eaa5b4ea0f58139489f0a00de3febcaf97b1ef9f8
Terms gate
No extra terms beyond the license.

Read the license text

Licenses are checked against the license table. A custom license passes only after a person reads it.

Provenance

From: unsloth <huggingface.co/unsloth>Newsgroups: alt.freeweights.speechSubject: csm-1bDate: 2026-11-15Commit: 39e8c75Signed: 2DC28CC7B26A283B ✓
Upstream
unsloth/csm-1b
Pinned commit
39e8c756bec133ad7eb9ea1097c84a2bd891c949
Manifest
csm-1b.json · .minisig
Manifest sha256
082dd4aeb43a532a47ab7da3229c6264f5e02a222aafdea6e120d1beaf0cb191
Signature
minisign, Ed25519, key 2DC28CC7B26A283B
Created
2026-11-15 02:46 UTC
Generator
freeweights-manifest/0.1.0
Takedowns
None.

How to verify

$ curl -O https://freeweights.allternit.com/manifests/unsloth/csm-1b.json $ curl -O https://freeweights.allternit.com/manifests/unsloth/csm-1b.json.minisig $ minisign -Vm csm-1b.json -P RWQ7KGqyx4zCLXtUFOqvfv8L3g+8fpKJ1FsuxPyOYMF+4KufbUxKq1Oq $ shasum -a 256 <file> # compare with the Files tab

A manifest whose signature fails must be rejected. A file whose size or sha256 does not match must be discarded. Verify a download

Model tree

Parent

sesame/csm-1b (not in this catalog) · this model is a finetune of it

No model in the catalog names this one as its parent.

Get it
Download
$ HF_ENDPOINT=https://freeweights.allternit.com hf download unsloth/csm-1b
Open in Freeweights Studio

Pull, verify and run it in the Allternit app on Desktop, web or phone.

Signed manifest
minisign, key 2DC28CC7B26A283B. csm-1b.json. Provenance. Takedown history: none.
From: MIT <huggingface.co/MIT>Subject: ast-finetuned-audioset-10-10-0.4593
From: onnx-community <huggingface.co/onnx-community>Subject: ast-finetuned-audioset-10-10-0.4593-ONNX
From: Edge0 <huggingface.co/Edge0>Subject: Audio8-TTS-Preview-0.6b
From: Edge0 <huggingface.co/Edge0>Subject: Audio8-TTS-Realistic-Air
From: facebook <huggingface.co/facebook>Subject: audiobox-aesthetics
From: mlx-community <huggingface.co/mlx-community>Subject: chatterbox-4bit