Seed #1540 is one entry in the Instruments 1-by-1 pillar of Calm Sound Archive. It is generated in the browser with the Web Audio API, so nothing is streamed and nothing is downloaded: the same seed number always produces the same piece of audio.
What you are hearing
Karplus-Strong plucked strings: a short noise burst circulates through a delay line, producing a harp-like tone whose brightness is set by the damping factor.
The musical material uses F Lydian at 50 BPM, tuned to 963 Hz. A binaural offset of 7.4 Hz separates the left and right channels slightly, which is what gives the track its width on headphones.
When to use it
Use it when you want a single instrument and nothing else — no bed of noise, no percussion, no vocals. This seed leans toward study & focus and runs at 50 BPM, so it moves slowly enough to sit under conversation or sleep.
Technical parameters
| Seed | #1540 |
|---|---|
| Pillar | Instruments 1-by-1 |
| Instrument | Felt Piano |
| Layer | Soft Hall |
| Engine | Karplus-Strong Celtic Harp |
| Scale | F Lydian |
| Tempo | 50 BPM |
| Tuning | 963 Hz |
| Binaural offset | 7.4 Hz |
| Filter ceiling | 2386 Hz |
How to listen
- Press play and choose a session length between five minutes and eight hours.
- Headphones give the binaural layer room to work; speakers still play the track but flatten the stereo image.
- Keep the volume where you can still hear the room. The fade-out at the end of a session is ten seconds, not a hard stop.
How this seed differs
Seeds in the Instruments 1-by-1 pillar share an engine family, but the parameters are not interchangeable. Here the filter ceiling sits at 2386 Hz and the binaural offset at 7.4 Hz. For comparison, seed #1539 cuts at 1758 Hz, this one at 2386 Hz; seed #1541 runs at 65 BPM, faster than the 50 BPM here.
The tuning is 963 Hz, which shifts the whole scale away from the more common 432 Hz reference. At 50 BPM the phrase repeats roughly every 4.8 seconds, so the loop is long enough that it does not feel like a short sample on repeat.
When this one works best
When you want one instrument and nothing else, usually during focused work or a short practice session. It is also the pillar that works best on laptop speakers, because there is no low-frequency bed to lose.
The mood tag for this seed is Study & Focus. Treat it as a starting point rather than a rule: the same track can sit under a work session at low volume and under sleep at an even lower one.
Questions about #1540
Does this seed download any audio?
No. The track is synthesised in the browser when you press play. Nothing is streamed, and there is no MP3 file behind it, which is why the same seed number always sounds the same on any device.
Can I leave it running for eight hours?
Yes. The timer goes up to eight hours and fades out over the last ten seconds instead of cutting abruptly. If you only need a short reset, the five-minute default is already selected.
Why does it sound different from the neighbouring seeds?
Because the engine reads the seed number to set the filter, the tuning, the tempo and the stereo offset. Small changes in those values change the texture more than a change of instrument would.