We present MGM-Omni, a unified Omni LLM for omni-modal understanding and
expressive, long-horizon speech generation. Unlike cascaded pipelines that
isolate speech synthesis, MGM-Omni adopts a “brain-mouth” design with a
dual-track, token-based architecture that cleanly decouples multimodal
reasoning from real-time speech generation. This design enables efficient
cross-modal interaction and low-latency, streaming speech generation. For
understanding, a unified training strategy coupled with a dual audio encoder
design enables long-form audio perception across diverse acoustic conditions.
For generation, a chunk-based parallel decoding scheme narrows the text speech
token-rate gap, accelerating inference and supporting streaming zero-shot voice
cloning with stable timbre over extended durations. Compared to concurrent
work, MGM-Omni achieves these capabilities with markedly data-efficient
training. Extensive experiments demonstrate that MGM-Omni outperforms existing
open source models in preserving timbre identity across extended sequences,
producing natural and context-aware speech, and achieving superior long-form
audio and omnimodal understanding. MGM-Omni establishes an efficient,
end-to-end paradigm for omnimodal understanding and controllable, personalised
long-horizon speech generation.