Google Flow + Veo 3 Audio (as of 2026-02-22): A Creator’s Workflow for Clean Dialogue, SFX, and Music in One Pass

Why Flow + Veo audio is different (and why it breaks more often than visuals)

Flow is designed to help you turn ideas into cinematic clips and scenes using Veo. (https://blog.google/innovation-and-ai/products/flow-video-tips/) And it’s being used at real scale: Google says more than 35 million videos have been generated since Flow launched in May. (https://blog.google/innovation-and-ai/products/flow-video-tips/)

But audio is a different kind of “physics” than images.

• Visual errors can be hidden with motion, cuts, or style.
• Audio errors (mumbled words, late SFX, music overpowering dialogue) are instantly noticeable—and they ruin conversion-focused creatives fastest.

Also, audio and dialogue generation in Flow is explicitly described as experimental, and the Google guidance says it can be generated by selecting Veo 3 in the model picker. (https://blog.google/innovation-and-ai/products/flow-video-tips/)

So your workflow needs two things:

1. A decision tree for when to generate audio in-model vs keep video silent.
2. A prompt structure that ties sound to visual beats without pretending you can get frame-perfect sync.

Before you generate: decide between (A) in-model audio vs (B) silent video + external audio

Treat this as a creative production decision, not a prompting decision.

Decision tree (quick)

Choose A — generate audio in-model if:

• You want “one-pass” ideation: a draft with voice + SFX + music to pitch internally.
• You’re making concept tests where polish is less important than speed.
• Your script is short enough to fit comfortably inside the clip.

Choose B — generate silent video, add audio later if:

• You need exact brand VO, legal disclaimers, or perfect music licensing control.
• You’re cutting multiple clips into a longer edit with continuity requirements.
• You anticipate heavy audio post (ducking, mastering, ADR).

Pros/cons by role

For marketers

• A (in-model audio): Faster to get to a shippable “feels like an ad” draft. Risk: dialogue intelligibility and mix may vary take to take.
• B (silent + external): More reliable for performance campaigns and compliance. Tradeoff: extra tooling and time.

For creators

• A: Great for storyboards, animatics, mood pieces, or rapid iteration.
• B: Better if you have signature sound design or need precise timing for edits.

One more practical constraint from Google’s Flow tips: speech is less likely to be generated if the requested dialogue doesn’t fit in an 8‑second clip (and also if it involves minors). (https://blog.google/innovation-and-ai/products/flow-video-tips/)

As of 2026-02-22, don’t assume longer dialogue will “just work.” Write for short clips.

The 3-part “Sound Map” prompt: Dialogue → SFX → Music (with timing anchors)

Google’s Flow prompt guidance encourages detailed prompts for better creative control, and it specifically calls out audio and dialogue as elements to consider (alongside subject/action, composition/camera, location/lighting, and style). (https://blog.google/innovation-and-ai/products/flow-video-tips/)

Here’s a practical way to implement that audio guidance without overcomplicating your prompt:

H3 Sound Map technique

Add a dedicated audio block with three layers:

1. Dialogue: who speaks, tone, pace, and exact words.
2. SFX: 2–5 key sound beats that support what’s happening on screen.
3. Music: a bed that matches the vibe, with an explicit instruction to stay under the voice.

Then, tie each audio layer to simple time ranges:

• 0–2s hook
• 2–6s payoff / demo
• 6–8s CTA (or 6–12s if your environment supports longer—don’t assume.)

These anchors do two things:

• They reduce “late SFX” and “music starts too strong” failure modes.
• They make iteration surgical (you can adjust the 2–6s segment without rewriting everything).

H3 Guardrails for dialogue reliability

• Keep VO lines short.
• Use plain words.
• Tell the model how to mix: “voice forward, music low, SFX subtle.”

If you’re using Flow, remember: audio/dialogue is experimental and depends on selecting Veo 3 in the model picker. (https://blog.google/innovation-and-ai/products/flow-video-tips/)

A fill-in template (copy/paste): 8s ad with VO + 3 SFX beats + music bed

Use this to generate a consistent first draft, then iterate.

H3 Template

Prompt:

• Format: 8-second vertical ad, modern UGC style, natural handheld phone camera.
• Visuals: [product] in [location], [action], bright natural light, close-ups with quick cutaways.
• On-screen text (optional): [3–5 words max].

SOUND MAP (0–8s)

• 0–2s Dialogue (hook): [one short sentence].
• 2–6s Dialogue (benefit): [one short sentence].
• 6–8s Dialogue (CTA): [one short sentence].
• SFX:
  • 0–2s: [SFX #1 tied to action]
  • 2–6s: [SFX #2 tied to action]
  • 6–8s: [SFX #3 tied to CTA gesture]
• Music: [genre/mood], starts at 0s, stays low under dialogue, slightly lifts at 6–8s, clean ending.
• Mix notes: voice clear and front; music ducked under speech; SFX subtle and never masks words.

Two complete prompt examples (copy/paste)

These are intentionally written to be “one pass” prompts you can drop into Flow and then refine.

H3 Example 1: UGC-style ad read (clean voiceover)

Prompt:

Create an 8-second vertical UGC-style ad. A creator stands in a bright kitchen holding a small portable blender. Natural handheld phone camera, quick close-ups of the lid clicking, the blade spinning, and a smooth pour into a glass. Friendly, real, not overly polished.

SOUND MAP (0–8s)

• 0–2s Dialogue (hook), upbeat and conversational: “I’ve been using this mini blender every morning.”
• 2–6s Dialogue (benefit), confident and clear: “It blends fast, and it’s easy to rinse—no mess.”
• 6–8s Dialogue (CTA), energetic but not shouted: “Grab it and make smoothies anywhere.”
• SFX:
  • 0–2s: soft plastic click as the lid snaps on
  • 2–6s: short blender whirr that fades quickly under the words
  • 6–8s: gentle pour into glass + a light “ding” accent when the product is shown
• Music: light pop beat, warm and optimistic, low volume under all speech; slightly brighter at 6–8s; stop clean at the end.
• Mix notes: dialogue must be the loudest element; music and SFX should never cover words.

H3 Example 2: Cinematic product reveal (dialogue + SFX + score)

Prompt:

Create an 8-second cinematic product reveal. A sleek matte-black smartwatch sits on a reflective surface in a dark studio. Slow push-in camera, dramatic rim lighting, floating dust motes, shallow depth of field. Cut to a close-up of the watch face lighting up, then a final hero shot.

SOUND MAP (0–8s)

• 0–2s Dialogue, calm and premium: “Meet the watch that keeps up.”
• 2–6s Dialogue, measured and confident: “Bright display. Smooth controls. All-day comfort.”
• 6–8s Dialogue, subtle CTA: “Ready when you are.”
• SFX:
  • 0–2s: soft low-frequency whoosh as the camera moves in
  • 2–6s: delicate tech UI blips when the screen animates
  • 6–8s: crisp metallic tick as the final hero shot lands
• Music: cinematic minimal score, pulsing sub-bass and airy pads; restrained under dialogue; lift slightly at 6–8s; end with a clean resolving note.
• Mix notes: premium and clean; keep reverb subtle; ensure every word is easy to understand.

Workflow in Flow: model picker, iteration loop, and versioning takes

Google’s Flow tips highlight using detailed prompts for more control. (https://blog.google/innovation-and-ai/products/flow-video-tips/) They also note that audio and dialogue are prompt elements you can specify, and that audio/dialogue generation is experimental via Veo 3 in the model picker. (https://blog.google/innovation-and-ai/products/flow-video-tips/)

H3 Practical iteration protocol (prevents regressions)

After your first generation, run this loop:

1. Name the take by what you’re testing (e.g., Take_03_dialogue_clearer).
2. Change ONE audio variable per revision:
   • Dialogue clarity (pace, pronunciation, fewer words)
   • SFX density (fewer/lower/shorter)
   • Music energy (calmer vs more driving)
3. Keep the rest identical.

This matters because tweaking multiple audio layers at once makes it hard to diagnose what fixed (or broke) the mix.

H3 Use assistants to rewrite, not to “guess”

Google notes Gemini can help refine prompts, expand ideas, or brainstorm. (https://blog.google/innovation-and-ai/products/flow-video-tips/) A good use here is: paste your Sound Map and ask for three alternate hook lines that are shorter (so they’re more likely to fit).

Quality control checklist (under 60 seconds)

Run this after every generation—fast enough to keep momentum.

• Dialogue intelligibility: can you understand every word on phone speakers?
• Timing: do the hook and CTA land in the intended time ranges (0–2s, 6–8s)?
• Masking: do SFX ever cover consonants (t/k/s sounds)?
• Music ducking: is music clearly lower than voice throughout?
• Continuity: do sound textures match the visuals (no “big room” reverb in a tight close-up)?

If you fail any one item, don’t “hope it’s fine.” Make a single-variable revision.

Fixes when it goes wrong: 7 fast prompt edits

Use these as patch notes to your Sound Map.

H3 1) Mumbled or unclear speech

• Shorten sentences.
• Add: “slow, articulate, no slurring; voice forward.”

H3 2) Dialogue doesn’t fit

Google warns speech is less likely if the dialogue doesn’t fit in an 8-second clip. (https://blog.google/innovation-and-ai/products/flow-video-tips/) Fix by:

• Cutting words by 30–50%.
• Moving detail to on-screen text instead of VO.

H3 3) SFX arrives late or feels random

• Reduce to 2–3 SFX beats.
• Bind each to a visible action: “SFX exactly when lid snaps on (0–2s).”

H3 4) Music overpowers voice

• Add a direct mix instruction: “music at low volume, always under speech; duck music during all dialogue.”

H3 5) Wrong vibe (too comedic / too intense)

• Specify tone words for the voice: “warm and trustworthy” or “calm and premium.”
• Specify music references by attributes (tempo/genre/instrumentation), not brand names.

H3 6) Audio feels “too busy”

• Replace multiple SFX with one “support” sound.
• Ask for “minimalist sound design; prioritize clarity.”

H3 7) Ending feels abrupt

• Add: “clean button ending; music resolves at 7.8–8.0s.”

Export handoff: when to stop iterating and finish in an editor

Stop generating and move to your editor when:

• The picture is right and the sound intent is proven, but the mix needs precise control.
• You need consistent loudness across multiple ads.
• You’re building a longer cut from multiple clips.

In other words: use in-model audio to get to a strong draft fast, then finish like a normal production.

FAQ

How do I turn on audio/dialogue in Flow?

Google’s Flow tips say audio and dialogue generation is experimental and can be generated by selecting Veo 3 in the model picker. (https://blog.google/innovation-and-ai/products/flow-video-tips/)

Why did my clip generate without the requested speech?

Google notes speech is less likely when the dialogue doesn’t fit in an 8-second clip (and also if it involves minors). (https://blog.google/innovation-and-ai/products/flow-video-tips/)

Should I write audio directions in the same prompt as camera and lighting?

Yes. Google recommends detailed prompts for more creative control, and lists audio/dialogue among the elements to consider. (https://blog.google/innovation-and-ai/products/flow-video-tips/)

Is Veo 3.1 relevant if I’m working in Flow?

If you’re using Veo on Vertex AI, Google Cloud describes Veo 3.1 as generally available for production and highlights rich synchronous audio and creative controls. (https://cloud.google.com/blog/products/ai-machine-learning/ultimate-prompting-guide-for-veo-3-1) In Flow specifically, follow Flow’s model picker guidance (and treat audio as experimental). (https://blog.google/innovation-and-ai/products/flow-video-tips/)

Related reading

• Veo 3.1 release date & launch notes
• Veo 3 API features guide
• What is the Veo 3 API?

CTA: Build your own generation pipeline with Veo3Gen

If you’re ready to move from one-off tests to a repeatable workflow—batching variants, tracking prompt versions, and integrating with your post-production stack—explore the Veo3Gen endpoints and plans:

• Start with the docs: /api
• Review options for your team: /pricing

Try Veo3Gen (Affordable Veo 3.1 Access)

If you want to turn these tips into real clips today, try Veo3Gen:

• Start generating via the API: /api
• See plans and pricing: /pricing

Sources

• https://blog.google/innovation-and-ai/products/flow-video-tips/
• https://cloud.google.com/blog/products/ai-machine-learning/ultimate-prompting-guide-for-veo-3-1
• https://ltx.studio/blog/veo-prompt-guide
• https://www.datacamp.com/tutorial/veo-3-1-complete-guide-with-examples