MiniMax-H3 Turbo LoRAs for ComfyUI

This repository contains MiniMax-H3 Turbo LoRAs converted and optimized for ComfyUI:

• dynamic-rank FL2V and Ref2V LoRAs derived from the official ComfyUI weights in lightx2v/Minimax-h3-Turbo;
• pruned/curve-form compatibility conversions of the Turbo LoRAs released by larryvrh.

These LoRAs accelerate MiniMax-H3 video and synchronized-audio generation by reducing the required number of sampling steps.

Update — LightX2V FL2V and Ref2V Dynamic-Rank LoRAs

Three dynamically resized BF16 LoRAs are now included. Their source weights were published in the correct MiniMax-H3 ComfyUI layout by:

lightx2v/Minimax-h3-Turbo

New files

The LightX2V files were already supplied in the correct ComfyUI namespace and QKV layout. No namespace conversion or AdaLN pruning was required.

How the LoRAs were resized

Each LoRA was compressed using an exact compact SVD calculated from its LoRA A/B factors without materializing the full dense weight updates.

The process:

1. Treats every attention, MLP and token-refiner projection independently.
2. Separates fused QKV adapters into their original Q, K and V projections.
3. Calculates the exact singular spectrum of each effective B @ A update.
4. Selects a dynamic rank independently for every projection.
5. Preserves one additional safety rank beyond the Frobenius-energy threshold.
6. Rebuilds balanced factors as A = sqrt(S) × Vh and B = U × sqrt(S).
7. Re-fuses Q, K and V using concatenated A factors and a block-diagonal B matrix.
8. Bakes the source alpha / rank scale into lora_B.
9. Removes the no-longer-required alpha tensors.
10. Saves all output tensors as BF16.

All three files target the same projection-level average rank:

• Rank sum: 6778
• Projection count: 312
• Average projection rank: 21.724359
• Filename rank: floor(21.724359) = 21

Q, K and V are counted separately. The stored rank of a fused QKV adapter is the sum of its three independently selected ranks.

Resize results

The Ref2V source was reduced from approximately 1,865.57 MiB to 311.79 MiB, an 83.29% reduction. The v1.1 768p source (1,865.57 MiB) was reduced to 891.65 MiB (−52.21%) at rank 64 and to 375.55 MiB (−79.87%) at rank 28.

A separate Frobenius threshold was solved for each LoRA because their singular-value distributions differ. Reusing one fixed threshold would not produce the same average rank.

Ref2V numerical validation

Direct comparison between the original and resized effective LoRA updates produced:

These are numerical weight-reconstruction measurements, not a perceptual video-quality score.

FL2V 4-step v1.1 768p numerical validation

Direct comparison between the v1.1 source and each resized variant produced:

These are numerical weight-reconstruction measurements, not a perceptual video-quality score.

Structural validation

Every resized LightX2V file contains:

Validation confirmed:

• all tensors contain finite BF16 values;
• every LoRA A tensor has a matching LoRA B tensor;
• ComfyUI recognizes all 208 adapters and all 416 tensors;
• no incompatible or unresolved tensors remain;
• QKV rank columns remain block-diagonal and ordered as Q, K and V;
• the original effective LoRA scale is preserved;
• the exact average projection rank is 21.724359.

Workflow Example

The following output was generated with the recommended pruned-model workflow using the v4 step-600 EMA LoRA.

Current workflow

Download the current ComfyUI workflow

• Workflow: fl_minimax_h3_turbo_lora_example_workflow.json
• LoRA: minimax_h3_turbo_v4_step600_ema_pruned_comfyui.safetensors
• Steps: 6–8
• Sampler: Euler
• Scheduler: Beta
• LoRA strength: 1.0
• Video sigma shift: 12
• Audio sigma shift: 4–6

The previous workflow remains available here:

Download the previous workflow

View the previous workflow output

Included Files

LightX2V dynamic-rank LoRAs

Pruned/curve-form compatibility conversions

Workflows and assets

EMA and non-EMA files contain different tensor values and are retained separately.

Pruned/Curve-Form Compatibility Conversions

The older full-model Turbo LoRAs use keys such as:

blocks.0.attn.qkv_proj.lora_A.weight

ComfyUI expects:

diffusion_model.blocks.0.attn.qkv_proj.lora_A.weight

The compatibility conversion applies:

• blocks.* → diffusion_model.blocks.*
• token_refiner.* → diffusion_model.token_refiner.*

The original full-model LoRAs also contain AdaLN adapters whose dimensions do not match the pruned/curve-form MiniMax-H3 checkpoint. Those incompatible adapters were removed.

The removed adapters consist of 50 AdaLN projection pairs from blocks.0 through blocks.49 and one pair from final_layer.adaln_proj.linear.

These files are partial compatibility conversions and should not be assumed to behave identically to the original full-model LoRA used with its intended complete MiniMax-H3 base model.

The LightX2V dynamic-rank LoRAs do not use this pruning process.

Usage

Place the LoRA files in:

ComfyUI/models/loras/

Load the selected LoRA with its compatible MiniMax-H3 model and workflow.

Recommended starting strength:

1.0

If adjustment is needed, test approximately:

0.8–1.2

When comparing files, keep the following identical:

• prompt;
• seed;
• resolution;
• frame count;
• base model;
• conditioning inputs;
• sampler;
• scheduler;
• LoRA strength;
• sigma shifts;
• workflow.

Sampling Guidance

Four steps

Maximum speed and useful for rapid previews. Use the matching four-step LightX2V FL2V or Ref2V workflow.

Six steps

A good speed-to-quality compromise for the v4 step-600 EMA pruned conversion.

Eight steps

Recommended when prioritizing quality, motion consistency and synchronized-audio stability.

For the existing pruned-model workflow, start with:

• Steps: 8
• Sampler: Euler
• Scheduler: Beta
• LoRA strength: 1.0
• Video sigma shift: 12
• Audio sigma shift: 4–6

Follow the source project recommendations when using the LightX2V LoRAs:

lightx2v/Minimax-h3-Turbo

Audio and Scheduler Notes

MiniMax-H3 generates video and synchronized audio as separate streams with different scheduling requirements.

Incorrect audio scheduling may cause:

• severe distortion;
• noise-like output;
• unstable or blown-out audio;
• completely broken audio.

If audio is unstable, check:

• sampler and scheduler configuration;
• audio and video sigma shifts;
• ComfyUI version;
• MiniMax-H3 sampling implementation;
• custom sampler nodes;
• whether the workflow matches the selected FL2V or Ref2V LoRA.

Broken audio should not automatically be attributed to the LoRA.

Optional Acceleration

These LoRAs may be used with compatible ComfyUI acceleration methods such as:

• Comfy Kitchen attention;
• SageAttention;
• Sol Attention;
• Spectrum.

These methods are optional and are not included in this repository. Some attention backends replace one another rather than stacking, and patch order depends on the implementation.

For few-step Turbo workflows, establish a clean baseline before adding approximate attention or trajectory-forecasting methods.

Attribution

LightX2V LoRAs

The dynamically resized FL2V and Ref2V LoRAs are derived from the official ComfyUI-compatible files released by:

lightx2v/Minimax-h3-Turbo

Credit for the source weights, training and release belongs to the LightX2V project and its contributors.

This repository provides only the dynamic-rank BF16 resizing, packaging and validation described above.

Original Turbo LoRAs

The older Turbo LoRA weights, training work and distillation method were released by:

larryvrh/MiniMax-H3-Turbo-Lora

Original ComfyUI Turbo custom node:

ComfyUI-MiniMax-H3-Turbo

This repository does not claim authorship of:

• the original LoRA weights;
• LoRA training or distillation;
• the few-step sampling methods;
• MiniMax-H3 video/audio scheduling;
• the MiniMax-H3 base model;
• the pruned/curve-form checkpoint;
• the LightX2V source weights;
• the original project documentation or generation code.

The modifications provided here are limited to:

• pruned/curve-form ComfyUI compatibility conversions;
• namespace adjustments;
• removal of incompatible AdaLN adapters where required;
• exact dynamic-rank SVD resizing of the LightX2V ComfyUI LoRAs;
• BF16 safetensors packaging and validation.

Please retain attribution and comply with the licenses and terms of the original LoRAs and MiniMax-H3 base model when using or redistributing these files.