Sume timeline with silent audio: audio.mode silence and its limits
Set audio.mode to silence in Sume Timeline 1.0 for a declared length with no spine file. Do not send url, parts, gain_db or source_in, and no ducking bed.
For a silent Sume Timeline 1.0 render, send audio.mode: "silence" with audio.duration_seconds (1 to 1800). The job gets a declared length with no spine file. In that mode you must not send url, parts, gain_db or source_in, and a soundtrack with duck_db needs a real spine, so it is not available. Without silence and without a spine you get audio_url_required. Source: Timeline 1.0, read 2026-10-06.
What combinations work?
The rules for the audio block.
| Audio setup | Allowed |
|---|---|
url alone | Yes, one hosted spine |
parts[] (up to 20) | Yes, not with url |
mode: "silence" plus duration_seconds | Yes |
Silence plus url, parts, gain_db or source_in | No |
No url, no parts, no silence | audio_url_required |
What else stays the same?
Video slots still need video[0].start of 0, increasing starts, and a render price of $0.10 per ceil output minute. Use the unbilled /plan call to check the program first.
Sources
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