Fish Audio S2.1 Pro is a text-to-speech model for turning a script into expressive spoken audio. In OpenCake, it can produce a new voiceover with the default voice or use a Fish Audio voice ID for a custom voice that you are authorized to use.
That makes the model useful for product demos, UGC narration, explainers, localized ads, podcasts, training content, and reusable brand voices. Good results still depend on the script, punctuation, reference recording, and review process—not only the model selection.
What is Fish Audio S2.1 Pro?
Fish Audio S2.1 Pro is the expressive multilingual text-to-speech option available in OpenCake. It supports generated speech, custom voice IDs, adjustable speaking speed, multiple output formats, and latency choices. Fish Audio’s official TTS documentation recommends its Pro model for high-quality generation and supports both saved voice models and reference-based voice cloning.
See the current API behavior and supported controls: Official Fish Audio text-to-speech documentation
Fish Audio S2.1 Pro features in OpenCake
| Control | What it changes |
|---|---|
| Text | The words, punctuation, and delivery cues the voice will speak |
| Voice ID | Uses a saved Fish Audio voice model, including an authorized cloned voice |
| Speed | Adjusts delivery from 0.5× to 2× |
| Format | Exports MP3, WAV, PCM, or Opus |
| Latency | Balances maximum quality against faster generation |
| Model tier | Lets you choose the available Pro or free route |
How to generate text-to-speech with Fish Audio S2.1 Pro
- Open AI Models in OpenCake and select Fish Audio S2.1 Pro.
- Paste a clean script written for speech rather than a block of web copy.
- Leave Voice ID empty for the default voice, or enter a voice model ID you have permission to use.
- Start at normal speed and normal latency. Change one setting only if the first result reveals a specific problem.
- Choose MP3 for convenient publishing, WAV or PCM for editing, or Opus for an efficient modern delivery format.
- Review the credit estimate, generate, listen with headphones, and download the approved take.
Create a voiceover in the same workspace as your images and videos: Open Fish Audio S2.1 Pro in OpenCake
How to write a better AI voiceover script
Write for the ear. Use short sentences, contractions, natural pauses, and one idea per breath. Spell out unusual abbreviations and read product names aloud before generation. Punctuation can guide rhythm, but excessive ellipses, capital letters, or stage directions may create unnatural delivery.
For a 15-second UGC ad, start with the hook, move to one concrete benefit, and finish with one call to action. Generate that compact version before expanding the script. A voice model cannot make a crowded script feel relaxed without either speeding up or cutting words.
How authorized voice cloning works
Voice cloning uses a recording to create a reusable voice model. Fish Audio recommends at least 10 seconds of clean audio and notes that a longer 30–60 second sample can help when a result sounds robotic or does not resemble the speaker. Record one person in a quiet, soft room without music, television, fans, or other voices.
Prepare cleaner reference audio with the provider’s recording guidance: Fish Audio voice-cloning best practices
Only clone your own voice or a voice whose speaker has given informed permission for the intended use. Do not clone a celebrity, customer, employee, or creator from an online clip without authorization. Keep a record of consent, define where the voice may be used, and provide an easy way to withdraw permission for future campaigns.
Best settings for common voiceover jobs
| Use case | Starting point |
|---|---|
| UGC ad | Normal or slightly faster speed, conversational script, MP3 |
| Product explainer | Normal speed, deliberate punctuation, WAV for editing |
| Podcast or narration | Normal latency, moderate sentence length, WAV or high-quality MP3 |
| Localized ad | Native-language script review, normal speed, pronunciation check |
| Interactive prototype | Balanced or low latency, short responses, Opus or MP3 |
Fish Audio S2.1 Pro quality checklist
- Every product name, number, price, and call to action is pronounced correctly.
- The pace leaves enough room for natural emphasis and visual timing.
- Volume and tone remain consistent across separately generated sections.
- The voice is authorized for this audience, channel, territory, and campaign.
- The exported format matches the next editing or publishing step.
- A human fluent in the target language reviews localized speech before launch.
The bottom line
Fish Audio S2.1 Pro gives OpenCake users a practical route from script to expressive speech. Start with a compact spoken-language script, use clean and authorized voice references, keep the initial settings neutral, and judge the result in the context of the final video. The best take is the one that communicates clearly—not simply the one with the most dramatic voice.