LTX-2 (Open-Source) Guide: Generate Synchronized Video + Audio in One Model

What Is LTX-2?

LTX-2 is a DiT-based audio-video foundation model from Lightricks designed to generate synchronized video and audio within a single model. Unlike most open video generators that produce silent clips, LTX-2 aims to create coherent motion and sound (ambient audio, foley, music, and even dialogue) together in one pass. You can explore the official sources here: Hugging Face model card, official site, paper, GitHub repo, and the prompting guide.

The big promise for creators is practical: generate the visuals and the soundtrack in sync, without stitching together a silent video from one tool and audio from another. For teams doing rapid prototyping, local pipelines, and open-source experimentation, LTX-2 is especially interesting because it ships with open weights and tooling focused on running locally.

Main Features and Capabilities

• Open weights and local-first execution: designed to run in practical developer and creator workflows, not only hosted demos.
• Joint audio + video generation: produces synchronized sound and motion in a single generation process.
• Modern diffusion-transformer foundation: DiT-style backbone with separate modality capacity allocation (video heavier than audio).
• Multiple workflow modes: text-to-video, image-to-video, and video-to-video (depending on the pipeline you use).
• Production-friendly outputs: intended for coherent clips where audio matches scene events (ambience, foley, dialogue, music).
• Prompting support that explicitly includes audio: prompts can describe ambient sound, music and dialogue (with dialogue in quotes).

The Breakthrough: Synchronized Visuals and Sound in One Coherent Process

Most video diffusion models treat audio as an afterthought: you generate silent video first, then add music, foley, ambience, or dialogue later using separate tools. The result often feels "off" — footsteps don’t land when the foot hits the ground, crashes don’t align with motion, and the atmosphere doesn’t match the scene. LTX-2 is built specifically to solve this by generating audio and video together, so timing and semantics can line up naturally.

How LTX-2 Synchronizes Audio and Video

At a high level, LTX-2 uses an asymmetric dual-stream Diffusion Transformer: a larger video stream and a smaller audio stream. The two streams are coupled with bidirectional audio-video cross-attention so each modality can condition on the other during denoising. This means the audio stream can "see" evolving video context (motion, events, scene type) and the video stream can "feel" audio-relevant timing and structure. Both streams share timestep conditioning so they stay aligned across the diffusion process.

In practice, that architecture makes prompts like “a door slams loudly” more likely to produce a slam sound that hits when the door closes, not randomly. It also improves scene atmosphere: a rainy street should sound wet, a forest should have wind and distant birds, and a café scene should have low room tone, clinking cups, and muffled chatter.

Prompting for Audio: The Key to Getting the Full Advantage

Because LTX-2 is designed to generate sound, audio prompting is not optional — it’s a first-class control. The official prompting guide recommends describing ambient sound, music, foley and speech explicitly, and placing dialogue in quotation marks. It also encourages specifying language and accent when you include spoken lines. See: Prompting guide.

• Describe ambience: wind, rain, city hum, room tone, crowd murmur.
• Describe foley: footsteps, fabric rustle, keyboard clicks, door creaks, glass clinks.
• Describe music: genre, instrumentation, tempo, mood (e.g., “slow ambient synth drone”).
• Put dialogue in quotes: “We’re late—move!”
• Keep it coherent: pick sounds that match what’s visible on-screen.

3 Video Examples That Showcase Audio-Visual Sync

Below are three prompts designed to demonstrate LTX-2’s defining capability: synchronized visuals and sound generated together. Each example includes explicit audio instructions. Replace the placeholder URLs with your rendered outputs.

Example 1: Rainy Neon Alley With Footsteps + Distant Siren

Cinematic shot at night in a neon-lit alleyway, wet pavement with reflections, gentle rain falling, a person in a trench coat walks toward camera at a steady pace, subtle handheld sway, shallow depth of field, film grain. AUDIO: clear footsteps splashing in puddles synchronized with each step, steady rain ambience, distant city hum, a faint police siren passing far away, no music, no narration.

Example 2: Ocean Cliff With Waves + Wind + Seabirds

Nature documentary shot of powerful ocean waves crashing against jagged black cliffs under an overcast sky, slow left-to-right pan, sea spray in the air, moody color grade, realistic motion. AUDIO: loud waves crashing synchronized with visible impacts, gusty coastal wind, distant seabird calls, subtle low-frequency rumble from surf, no music, no dialogue.

Example 3: Coffee Machine Diagram-to-Action With Mechanical Foley

Close-up cinematic shot of an espresso machine pulling a fresh shot: portafilter locked in, steam wand briefly hisses, then espresso pours into a small cup, crema forming on top, warm tungsten lighting, shallow depth of field. AUDIO: precise mechanical clicks when handles move, short steam hiss synchronized with visible steam, espresso drip/pour sound aligned with the flow, soft café room tone in background, no music.

Getting Started

• Read the official overview: LTX-2 on Hugging Face and GitHub.
• Follow the audio prompting rules: Prompting guide.
• Start short (6–10 seconds) to validate sync, then iterate with small prompt changes.
• Be explicit about audio: ambience + foley + (optional) music/dialogue.
• Keep the audio coherent with the visuals to maximize perceived realism.

Conclusion

LTX-2 is one of the most important open-source releases in video generation because it treats audio as a first-class output rather than an afterthought. By generating synchronized visuals and sound together, it reduces the gap between “AI clips” and “usable scenes.” If your workflow involves storytelling, product demos, documentaries, or atmosphere-heavy scenes, LTX-2’s unified audio-video approach can save time and produce more believable results—especially when you prompt the audio intentionally.