Granite Speech 4.1 2B · OpenASR
IBM Granite Speech 4.1 — a 2B multilingual ASR model with strong English accuracy
Native speech-to-text in the OpenASR runtime — engineered for peak performance on CPU & GPU, no Python at inference time.
✨ Highlights
- 📊 Verified English WER: 0.54% — identical across fp16 / q8_0 / q4_k on OpenASR's frozen evaluation set
- 🌐 Six trained languages — English, French, German, Spanish, Portuguese, Japanese (auto-detected; no language token)
- 📦 Three quantization tiers: fp16 / q8_0 / q4_k — delivered in OpenASR's native .oasr format for local inference
- 🦀 Native in OpenASR —
.oasrpacks run with no Python at inference, engineered for peak performance on CPU & GPU
🚀 Quickstart
# 1. Install the OpenASR CLI · https://openasr.org
# 2. Pull a build (pick a quant — see the table below)
openasr pull granite-speech-4.1-2b:q8
# 3. Transcribe
openasr transcribe audio.wav --model granite-speech-4.1-2b
All builds for this model:
openasr pull granite-speech-4.1-2b:fp16
openasr pull granite-speech-4.1-2b:q8
openasr pull granite-speech-4.1-2b:q4
📦 Available builds
| Quant | File (.oasr) | Size | RAM peak | RTF · M1 CPU | RTF · M1 GPU | JFK ΔWER vs fp16 |
|---|---|---|---|---|---|---|
| fp16 | granite-speech-4.1-2b-fp16.oasr | 4.63 GB | 5.91 GB | 0.40× | 0.23× | 0.0% |
| q8_0 | granite-speech-4.1-2b-q8_0.oasr | 2.47 GB | 3.65 GB | 0.35× | 0.17× | 0.0% |
| q4_k | granite-speech-4.1-2b-q4_k.oasr | 1.55 GB | 2.63 GB | 0.29× | 0.15× | 0.0% |
RTF = real-time factor on the fixed 11s JFK clip (lower is faster); RAM peak measured per pack in an isolated subprocess. JFK ΔWER compares each quantized build's JFK transcript to this model's fp16 JFK transcript, so it measures quantization drift rather than absolute recognition accuracy. q8_0 is the recommended default — near-reference quality at a fraction of the footprint.
🧠 About Granite Speech 4.1 2B
Granite Speech 4.1 2B is a speech-recognition model from IBM Granite. Its
architecture pairs a 16-layer Conformer audio encoder with a Q-Former projector
feeding a 2B Granite decoder. The model auto-detects the source language through
free-text instruction-following and ships trained coverage for English, French,
German, Spanish, Portuguese, and Japanese. OpenASR distributes this model in
three quantization tiers -- fp16, q8_0, and q4_k -- packaged in the native
.oasr runtime format for local inference.
⚙️ How these packs were made
Converted from ibm-granite/granite-speech-4.1-2b with the OpenASR importer:
openasr model-pack core: convert_local_granite_speech_source_to_runtime_pack <src> <out>.oasr \
--package-id granite-speech-4.1-2b --quantization {fp16,q8-0,q4-k}
The .oasr container is GGUF-backed; packs use zero-copy mmap weight binding and graph
buffer reuse to keep peak memory low.
⚖️ License
These packs inherit the upstream model's license: Apache-2.0 (source). OpenASR packaging retains the upstream copyright and NOTICE; the only modifications are format conversion and quantization.
🙏 Acknowledgements
This pack is a redistribution of granite-speech-4.1-2b, created and released by IBM Granite (ibm-granite/granite-speech-4.1-2b) under the Apache License 2.0. OpenASR performs format conversion, quantization, runtime validation, and local-inference adaptation only; all model weights and training are the work of the original authors.
🔗 Links
- 🦀 OpenASR — https://github.com/QuintinShaw/openasr
- 🌐 Website — https://openasr.org
- 🤗 Upstream model — ibm-granite/granite-speech-4.1-2b