GET

/v1/schemas/fal/audio/fal-ai%2Fbytedance%2Fseed-speech%2Ftts%2Fv2

kind inputactivity audiohash 4e8a5f65extracted Jul 6, 2026version currentsource upstream spec ↗

Request body

9 properties · 1 required · 0 $defs
propertytypedescriptionconstraints
text*stringThe text to synthesize into speech.length ≤ 5000
output_formatenumOutput audio format. 'mp3' returns MP3 audio; 'opus' returns Opus audio in an Ogg container.mp3 | opus · default: "mp3"
sample_rateenumSample rate of the output audio in Hz.8000 | 16000 | 22050 | 24000 | 32000 | 44100 · +1 more · default: 24000
volumenumberVolume. 1.0 is normal volume, 0.5 is half, 2.0 is double.0.5 ≤ n ≤ 2 · default: 1
pitchintegerVoice pitch shift in semitones. 0 is normal pitch, -12 lowers by one octave, 12 raises by one octave.-12 ≤ n ≤ 12 · default: 0
languageenumForce the text to be read as a single language, disabling automatic language detection. Leave unset for automatic detection (including seamless Chinese/English mixing on bilingual voices). Codes: zh (Chinese), en (English), ja (Japanese), es-mx (Mexican Spanish), id (Indonesian), pt-br (Brazilian Portuguese), ko (Korean), it (Italian), de (German), fr (French).zh | en | ja | es-mx | id | pt-br · +4 more · nullable
voiceenumVoice to use for synthesis. The preset name encodes the voice and its supported language codes. 'mixed_en_zh' means the voice can seamlessly blend English and Chinese; separate codes (e.g. 'en_zh') mean the voice supports each language independently.vivi_mixed_en_zh_ja_es_id | mindy_en_es_id_pt_zh | stokie_en | dacey_en | tim_en | kian_en_zh · +35 more · default: "stokie_en"
voice_instructionstringOptional natural-language instruction that steers the delivery (tone, emotion, pace, volume), e.g. 'Speak in a cheerful tone' or 'Could you speak a bit slower?'. It is not spoken aloud and does not affect billing.nullable
speednumberSpeech speed. 1.0 is normal speed, 0.5 is half speed, 2.0 is double speed.0.5 ≤ n ≤ 2 · default: 1

Validate a payload

before you spend tokens
shell
$ curl -X POST https://modelschemas.com/v1/validate \
    -d '{"provider":"fal","endpointId":"fal-ai/bytedance/seed-speech/tts/v2","payload":{…}}'
→ {"valid": false, "errors": [{"path": "#", "keyword": "required", …}]}