Holiday jingle for ads: Spotify says listening starts in October

For a holiday jingle ad, call POST /v1/music-router/generate with a prompt that says the genre, tempo, instruments and length, then lay the track under your video as a Timeline soundtrack. Length goes in the prompt: the Music Router rejects duration and duration_seconds.

Spotify's newsroom post, read 2026-10-01, says holiday listening has already begun in earnest, and gives an October 30 global average start for holiday listening. Sume facts are from the Music Router and Timeline 1.0 docs.

What does Spotify say about holiday listening in October?

The post reports festive favorites streamed 36.2 million times a day on average, and more than 100,000 holiday playlists created in September alone. It gives October 30 as the global average start of holiday listening, with some countries earlier; Barbadian listeners ramp up as early as October 1. Those are Spotify's numbers about listening, not about ad performance.

How do I ask for a track of the right length?

The docs say to steer length in the prompt, with phrasing like "a 2-minute track" or section markers such as [0:00-0:30] Intro: .... Put exclusions in the positive prompt too, and say "Instrumental, no vocals" if you want a bed under a voiceover. negative_prompt is unsupported when non-empty. The prompt limit is 1-5000 characters. Music runs through model: "sume/music-auto" unless you name a routable id, and costs $0.125 per audio on the rate card.

curl -X POST https://api.sume.com/v1/music-router/generate \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: holiday-bed-001" \
  -d '{
    "model": "sume/music-auto",
    "prompt": "Warm acoustic holiday jingle, 100 BPM, sleigh bells and glockenspiel, a 30-second track. Instrumental, no vocals."
  }'

What happens if I send a duration?

It is refused. duration and duration_seconds are rejected, so a request that works on another music API with a seconds field needs rewriting as prompt text. Length is a steer, not a guarantee; check the finished track and, if it runs long, cut it in the next step. The post exact music length without a duration parameter covers that.

How do I put the track under the ad?

Timeline 1.0 accepts an optional soundtrack bed with url, gain_db, loop, fade_out_seconds (up to 10) and duck_db (0 to 20, which needs a real spine, not silence). If you stitch many clips, render.strategy is auto by default and chunks past 12 segments. A holiday ad in four phases, one clip each, stays well under that; see holiday ad creative by phase.