MiniMax H3 Runs Local, Generates Video with Real Audio—All in One Pass
Open-weight video models are rare. Rarer still are ones where audio isn't an afterthought—it's generated in the same pass as the visuals. MiniMax H3 arrived this August with both: open weights, native stereo audio, and day-zero ComfyUI support that let creators start experimenting locally within hours.
What actually shipped
MiniMax officially open-sourced H3, the omni-modal video model, on August 3, with native ComfyUI support landing the same day via pull request #15224, adding joint audio-video generation with four new nodes and six official workflow templates. H3 is a next-generation open-weights video model: feed it text, images, video, or audio and it generates video with real stereo sound, up to 2K, up to 15 seconds a clip.
The model is omni-modal—meaning it understands text, images, video, and audio together. It generates video with native stereo audio (voice, SFX, and music in a single pass). That's the difference. Traditional video generation makes a clip, and you stitch in audio separately. H3 doesn't split the work.
What people are actually making
ComfyUI workflow examples include a confident performer executing a fast dance routine on a neon-lit stage, with the camera tracking vertically before making a smooth arc around the subject, preserving natural body mechanics and facial expression with synchronized footsteps, crowd ambience, rhythmic electronic music, and cinematic lighting. Another workflow shows creating a graceful performance between a supplied first frame and last frame with controlled torso movement, expressive arm gestures, consistent identity, and a smooth camera transition, with motion naturally arriving at the final pose and synchronized rhythm with cinematic music.
The first striking examples included moving typography, hand-drawn effects, product graphics, animated title sequences, music, dialogue, and transitions—not simple cinematic shots. One documented workflow shows a silver watch resting on dark stone with soft light moving across the surface as the camera slowly pushes forward in a premium product commercial style.
Reddit r/StableDiffusion and r/comfyui threads show creators iterating on MiniMax H3 scenes in real time, combining it with LoRA training and control nets to shape character motion, lighting, and camera language.
What's actually good—and what isn't
The stereo audio generation is the genuine breakthrough. You provide a text prompt plus up to nine reference images, three short reference videos, and three audio clips, and the model produces a single MP4 with native stereo audio in one pass at up to 2K resolution and 24fps. No separate voice synthesis tool. No music track you have to license and sync. It all comes from one model.
The model's modulation weights (about 40% of the total parameters) could be pruned and replaced with a lookup table, dramatically shrinking the memory footprint with no loss in output quality, with weights shipped with int8 convrot quantization and custom kernels, reducing memory footprint from 123.6 GB in full precision to 42.5 GB, enabling a next-generation 2K video model to run locally on a GPU like the RTX 3060.
But there's a catch in the architecture itself. The complete hosted system is not fully local: H3-Context-IR and H3-Regenerate-2K remain API services, and the first public local release does not include MiniMax's sparse-attention implementation, so "open weights" is not mistaken for a fully open, offline 2K pipeline. Local workflow centers on a 768px short edge, while H3-Regenerate-2K regenerates an H3-Base 768p output together with the original context to reach 2K, but was not released as open weights at publication.
For creators working at 768p locally, that's functional. For 2K output, you're still hitting the API—which means cost per generation and a hosted dependency.
How to try it
MiniMax H3 is supported in ComfyUI with open weights: update ComfyUI to version 0.30.0 or later (native support merged in Comfy-Org/ComfyUI #15224), open Workflow → Browse Templates → Video, and choose any MiniMax H3 workflow. Download MiniMax H3 open weights for ComfyUI: FL2VA and Ref2VA checkpoints in bf16, INT8, pruned and NVFP4 files, plus six official workflow templates (T2V, I2V, R2V).
MiniMax launched H3 on July 31, then released the weights on August 3; the open-weight release makes it possible to run H3-Base locally for 768p video generation with native stereo audio using supported frameworks such as ComfyUI, without per-generation API fees.
You'll need VRAM. Comfy-Org repackaged the weights with pruning and int8, cutting the footprint enough that an RTX 3060 can run it with dynamic offloading. Older or lower-VRAM cards may require system-memory offloading and CPU fallback, which will slow generation significantly.
API pricing is $0.08/sec for 768P and $0.13/sec for 2K.