Sound

Low pass filter for audio

Cut everything above a frequency. Music from the next room, or a voice on the phone.

Shown on Sweet Sun, by Loyalty Freak Music

Before · the same request without it
After · Music from the next room.

The entry

Add it to a clip's effects list. Entries run in the order you write them.

{
  "type": "lowPass"
}

Settings

NameAcceptsDefaultWhat it does
cutoff5 to 21600 Hz700Frequencies above this are removed, in hertz.

Run it

The whole request behind the render above. Paste it as it is, or swap the file for your own.

job.ts
import { createClient, outputUrl } from "@rendobar/sdk";


const rb = createClient({ apiKey: process.env.RENDOBAR_API_KEY });


const job = await rb.jobs.run({
  type: "compose",
  params: {
    schemaVersion: 1,
    output: {
      format: "mp3"
    },
    timeline: {
      tracks: [
        {
          clips: [
            {
              asset: {
                type: "audio",
                src: "https://cdn.rendobar.com/compose/showcase/media/music.wav"
              },
              start: 0,
              effects: [
                {
                  type: "lowPass"
                }
              ]
            }
          ]
        }
      ]
    }
  },
});


console.log(outputUrl(job));

Install with npm i @rendobar/sdk. jobs.run() submits and waits, so it returns the finished job in one call.

terminal
curl https://api.rendobar.com/jobs \
  -H "Authorization: Bearer $RENDOBAR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"type":"compose","params":{"schemaVersion":1,"output":{"format":"mp3"},"timeline":{"tracks":[{"clips":[{"asset":{"type":"audio","src":"https://cdn.rendobar.com/compose/showcase/media/music.wav"},"start":0,"effects":[{"type":"lowPass"}]}]}]}}}'

Returns immediately with a job id. Poll GET /jobs/{id} or register a webhook rather than blocking on the request.

Questions

What does the lowPass effect do in compose?

Cut everything above a frequency. Music from the next room, or a voice on the phone. Music from the next room.

How do I add low pass to a video with an API?

Send a compose job to the Rendobar API with this entry in the timeline: {"type":"lowPass"}. Add it to a clip's effects list. Entries run in the order you write them. The request on this page is complete and renders as shown.

What are the default settings for low pass?

Every setting has a default, so the type on its own is enough: cutoff 700. Set only the ones you want to change.

Footage and sound

More in the reference

EQ More low end and more sparkle on a music bed. Compressor Even out a voice so quiet words and loud words sit at one level. Limiter Make music louder without letting the peaks clip. Noise gate Close the microphone when nobody is speaking, so the river drops away before and after the voice. High pass Cut the rumble under a voice. Wind, traffic and water live there. Loudness Bring a voice recorded far too quietly up to a streaming loudness.

See all 77 in the effects reference →