ComfyUI-MiniMax-H3-Turbo

Run MiniMax-H3 — joint video + synchronized audio — in 4 sampling steps instead of ~20, with the MiniMax-H3 Turbo LoRA.

Two nodes that drop straight into the official H3 workflow (text-to-video and image-to-video):

node	what it does
MiniMax-H3 Turbo LoRA	MODEL → MODEL, applies the turbo LoRA
MiniMax-H3 Turbo Sampler (4-step)	→ SAMPLER, feeds SamplerCustomAdvanced

⚠️ Early preview. The current LoRA is an early checkpoint — quality is well short of a finished model, but already a clear step up from the base at 4 steps. See the LoRA repo for details.

Install

🔄 Keep the node updated. It's actively evolving and features arrive in new versions (e.g. pruned-base support was added after the first release). Update via ComfyUI-Manager, or git pull if you installed manually.

Via ComfyUI-Manager — search "MiniMax-H3 Turbo" and install.

Or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/larryvrh/ComfyUI-MiniMax-H3-Turbo

Then restart ComfyUI.

Download the LoRA from larryvrh/MiniMax-H3-Turbo-Lora and put the .safetensors into ComfyUI/models/loras/.

You also need the base MiniMax-H3 model, VAEs and text encoder from the official release — see the MiniMax-H3 tutorial.

Use

Start from the official MiniMax-H3 workflow (t2v or i2v) and make two changes:

1. Insert MiniMax-H3 Turbo LoRA between the model loader and the sampler (... → Load Diffusion Model → MiniMax-H3 Turbo LoRA → SamplerCustomAdvanced), and pick the turbo .safetensors.
2. Replace the sampler feeding SamplerCustomAdvanced with MiniMax-H3 Turbo Sampler (4-step), and set the scheduler node to 4 steps (BasicScheduler, scheduler simple).

Everything else — the conditioning nodes, VAE decode, audio output — stays as in the official workflow, so both text-to-video and image-to-video work unchanged. A ready-made t2v workflow is in example_workflows/ — drag it into ComfyUI to see the wiring.

Base model: works with any MiniMax-H3 base — full (bf16, int8_convrot) and the pruned/curve variants (pruned_int8, pruned_fp8). The node detects a pruned base automatically and re-injects the LoRA's time-conditioning at run time (a small silu(t_emb) grid ships with the node for this), so one LoRA file covers every base.

Why a custom sampler

MiniMax-H3 denoises the video and audio streams on two different flow schedules (video shift 12, audio shift 3). ComfyUI's stock samplers step both streams on one schedule, which is fine at ~20 steps but badly over-steps the audio at 4 steps — the audio comes out distorted or blown out. This sampler steps each stream on its own schedule, so audio stays clean at 4 steps. If you load the LoRA and use a stock sampler at 4 steps and the audio is broken, this is why.

Notes

• Steps: 4 works, but this early checkpoint is under-trained, so the comfort zone for sharpness is 6–8 steps, not 4 (4 comes out softer). Any count ≥ 4 is valid and more steps look better. Scheduler stays simple.
• Resolution / length: width and height are multiples of 32 (short edge typically 768); frame count is at 24 fps and snaps to the model's 17·k+5 grid (124 ≈ 5 s). Validated range ~124–362 frames.
• VRAM: MiniMax-H3 is large (~33 B); an 80 GB GPU is comfortable.

License

Apache-2.0.