20 overlapping 15-second stings from one Lyria track for $0.135

One Timeline audio split job accepts up to 20 ranges and the ranges can overlap, so a single 2-minute Lyria track can become 20 fifteen-second stings starting every 5 seconds. The cost is $0.125 for the track plus $0.01 for the split, $0.135 in total. Generating 20 separate stings would cost 20 x $0.125 = $2.50.

The windows are 0 to 15 s, 5 to 20 s, and so on up to 95 to 110 s. The last window ends 10 seconds before the track does. Each range becomes its own file with its own audio_url, and the split is sample-domain, with no re-synthesis.

The request

Follow the rules on the Timeline audio page: operation: "split", a top-level url that is already this workspace's media.sume.com audio, ranges[] of 1 to 20, and an Idempotency-Key header. Do not send parts. The script builds the body and checks the two limits before you spend anything.

import json

ranges = [{"start": s, "end": s + 15} for s in range(0, 100, 5)]
assert len(ranges) == 20          # the split limit
assert ranges[-1]["end"] <= 120   # inside a 2-minute track

body = {
    "operation": "split",
    "url": "https://media.sume.com/artifacts/artf_demo/bed.wav",
    "ranges": ranges,
}
print(len(ranges), "windows, last ends at", ranges[-1]["end"], "s")
print(json.dumps(body)[:90], "...")

Cost and size

The split is a worker job with no provider inference, so the rate is flat at $0.01 per job whatever the number of ranges. The table shows what changes when you cut the 2-minute bed different ways.

Where 20 stings are used

A sting is a short musical punctuation: an ad end tag, a transition between scenes, a notification sound inside a Short. Twenty windows give you enough variety to assign a different one to each of 20 ad variants without paying for 20 generations. Pick the files by ear, because overlapping windows from the same track share a key and a tempo, which is what makes a set of stings sound like one brand.

If you need fewer, cut fewer. The price of the split job does not change with the number of ranges, so there is no saving in asking for 6 windows instead of 20, only less to review. If you need more than 20, run a second split on another range of the same file for another $0.01.

Caveats before you rely on it

Overlapping windows share audio, so ads that run together will sound alike. Cut at musical boundaries: at 120 BPM a bar is 2 seconds, so a 4-second step moves exactly two bars each time and keeps every window on a bar line, while a 5-second step moves 2.5 bars and every second window starts mid-bar. Twenty windows at a 4-second step reach 0 to 76 s for the starts and end at 91 s. The Music 1.0 page says tempo in a prompt is a direction, not a guaranteed value.

Keep the default wav output if you will join or re-cut the stings again. The docs say mp3 is smaller but adds priming padding at every edge. As a size check, if the output keeps CD-quality stereo (44.1 kHz, 16-bit, 176,400 bytes per second), each 15-second wav is about 2.6 MB and the 20 files about 53 MB; the docs do not state the output sample rate, so measure one file.