> For the full page index, fetch https://echonova.ai/llms.txt

# Playground

Voices, Text to Speech, Speech to Text, Sound Cleaning and your assets.

## Voices

- [Browse the voice library](https://echonova.ai/docs/playground/voice-library.md): Open the voice library, read what a voice row tells you, hear a preview, send a voice to Text to Speech and put it on an agent.
- [Filters, previews and favourites](https://echonova.ai/docs/playground/filters-previews-favourites.md): Narrow the voice library by search, dialect and voice traits, use the preview player, and keep a list of saved voices that follows you into every picker.
- [Dialects](https://echonova.ai/docs/playground/dialects.md): The dialects the voice library carries, how the library groups voices by them, what a dialect changes in generated speech and in an agent, and how to pick one for a region.
- [Choosing a voice](https://echonova.ai/docs/playground/choosing-a-voice.md): How a voice for narration differs from a voice for an agent, what to listen for in a preview, and which speech settings matter for each use.

## Text to Speech

- [Generate speech](https://echonova.ai/docs/playground/generate-speech.md): Turn written text into a spoken audio file in the portal, then listen to it and download it.
- [Add diacritics](https://echonova.ai/docs/playground/add-diacritics.md): Mark Arabic text with tashkeel before you generate with an Arabic voice, keep the marks you typed yourself, and know when the switch helps.
- [Voice settings](https://echonova.ai/docs/playground/voice-settings.md): Every control in the Text to Speech settings panel, with its label, range, default and what it changes.
- [Formats, quality and download](https://echonova.ai/docs/playground/formats-quality-download.md): The audio format a portal generation produces, the controls that affect its quality, the player, and how a downloaded file is named.
- [Text to Speech history](https://echonova.ai/docs/playground/tts-history.md): Find, replay and download earlier generations from the History section of the Text to Speech page.
- [Text to Speech limits and credits](https://echonova.ai/docs/playground/tts-limits-and-credits.md): The text limit and the other limits on the Text to Speech page, what a generation costs in credits as the portal shows it, and what happens when the balance runs out.

## Speech to Text

- [Transcribe a file](https://echonova.ai/docs/playground/transcribe-a-file.md): Upload an audio file or record from your microphone on the Speech to Text page, wait for the transcript, and read it in place.
- [Speech to Text formats](https://echonova.ai/docs/playground/stt-formats.md): Which files the Speech to Text page accepts, what the browser does to each format before upload, what a microphone take is saved as, and what the transcript is.
- [Immediate and queued transcription](https://echonova.ai/docs/playground/sync-versus-async.md): What the Speech to Text page is doing behind each state of its status line, how long it waits, what happens when you leave, and when the API answers in one call instead.
- [Read a transcript](https://echonova.ai/docs/playground/reading-results.md): Find your way around the Speech to Text Transcript card, play the audio against the text, switch between transcripts, and save a transcript as a file.
- [Speech to Text limits and credits](https://echonova.ai/docs/playground/stt-limits-and-credits.md): Every limit on the Speech to Text page with the message it shows, what a transcription costs in credits and when the credits are taken, and what you see when the balance cannot cover a file.

## Sound Cleaning

- [Clean a recording](https://echonova.ai/docs/playground/clean-a-recording.md): Upload a noisy recording on the Sound Cleaning page, compare the original with the cleaned version, and download the cleaned file.
- [Sound Cleaning formats, limits and credits](https://echonova.ai/docs/playground/cleaning-formats-limits-credits.md): The formats the Sound Cleaning page accepts, every limit with the message it shows, what a cleanup costs in credits and when the credits are taken.

## Assets

- [Assets and history](https://echonova.ai/docs/playground/assets-and-history.md): Find every speech generation, transcript and cleaned recording made in the workspace on the Assets page, filter and search them, play them again, download, rename and delete them.