Muffled Audio Maker

How to make audio sound muffled

Three steps, in your browser.

1. 1

   Add a file

   Drop an MP3, M4A, WAV or other audio file up to 100 MB and 30 minutes, or load the short voice clip on the page to try the presets first.

2. 2

   Pick a place and tune it

   Choose a preset, then press Play and move the cutoff and intensity sliders while you listen. Switch to Original at any point to compare.

3. 3

   Save the file

   Press Make it muffled. The whole file goes through the same filters as the preview and is saved as an MP3 at the bitrate you pick or as a 16-bit WAV.

The five presets

Each preset is a starting point. The cutoff slider runs from 150 Hz to 4 kHz on every preset.

• Next room and through a wall

  Next room starts at 1,500 Hz with a gentle slope and a short room echo, so words stay half clear. Through a wall starts at 450 Hz with a steeper slope and a little bass lift: you hear that someone is talking, not what they say.

• Underwater

  Starts at 350 Hz, and the cutoff slowly swings up and down about 0.7 times a second, with a longer, washy echo. That movement is what makes it read as water rather than a wall.

• Party next door

  Starts at 250 Hz and boosts the bass, so mostly the kick drum and bass line come through, much quieter than the original. Try it on a song.

• Phone in a pocket

  Starts at 900 Hz with no echo and a big volume drop, like a call or a recording made with the phone still in a jacket.

What makes a sound muffled

Is your recording muffled by accident?

If you came here because a recording already sounds dull, these are the usual causes. Most are fixed before the next recording, not after.

• The mic is covered or facing away

  A finger over the phone's mic hole, a case that blocks it, a lapel mic under a jacket or a laptop mic facing the wall. DPA notes that a mic on the chest already loses much of the 2 to 4 kHz range, and a dense windshield can do the same.

• Too far away in an echoey room

  From across a room the mic picks up more reflections than voice, and hard walls smear the words. Move the mic closer to whoever is speaking and pick a room with soft furnishings.

• A phone in a pocket or bag

  Fabric works as a low-pass filter, exactly like the preset on this page. Take the phone out and lay it on the table, mic side towards the speaker. Recording a meeting or a call? Tell everyone first and get their consent.

• Strong noise suppression

  Call apps and some phones remove background noise automatically. Set high, it can take parts of the voice with the noise and leave it thin or dull. Try a lower setting for recordings that matter.

• Low-quality call audio

  A phone line carries roughly 300 to 3,400 Hz, and many Bluetooth headsets switch to a narrower call mode while their mic is in use. Recording on the phone itself, or with a wired mic, keeps more of the voice.

Ideas for a muffled sound

• A scene in a video or a game

  Neighbors arguing, a radio in another apartment, a voice heard through a door: muffle the line and lay it under your scene.

• A song playing in another room

  Party next door or next room on a track gives the far-off music sound used in edits and short videos. Use music you have the rights to.

• A transition or a flashback

  Muffle a few seconds of dialogue or music to mark a dream, a memory or a character losing focus, then cut back to the clear version.

• Testing how speech holds up

  Hear how much of a voice message or an announcement survives a closed door or a cheap speaker before you send it out.