A video shot across a room is often too quiet to hear on a phone speaker. PlainLoud turns that sound up, lets you hear the result before you save, and writes a new file. The original stays where it was.

These steps match the Play listing as of November 2026. Every feature on that listing is free: no watermark, no trial, no subscription, and no in-app purchases.

Boost one video

  1. Install PlainLoud. You can also share a video to it from the gallery or a files app. You pick the file in Android’s picker, so the app does not ask for storage permission.
  2. If you do not want to guess, use auto loudness. It measures the video and sets the boost toward −16, −14, or −11 LUFS.
  3. Or move the volume yourself. The range is up to +30 dB, or down by up to 10 dB.
  4. Leave “prevent distortion” on. The look-ahead limiter is what stops a clap or a laugh from crackling once the quiet speech is louder.
  5. Switch between Original and Edited. The preview uses the same processing as the file you are about to save, so what you hear is what you get.
  6. Save, and leave the app open until it finishes. Long videos are streamed, not loaded whole into memory.
  7. Read the before-and-after loudness and peak. That is the check that the new file is actually louder.

The picture is copied as it is. Quality and size of the video stream stay the same. Only the sound is re-encoded. The new video goes to Movies/PlainLoud.

When the voice is muddy, not just quiet

The 6-band equalizer moves each band by up to 15 dB. The presets on the listing are Voice clarity, Bass boost, Treble boost, Music, Podcast, Less harsh, Phone speaker, and Night. You can save your own. A compressor evens out loud and quiet parts. A low cut reduces wind, hum, and handling noise. Mono fixes a clip that only plays in one ear.

You can save audio only (M4A or WAV), or save a copy of the video with the sound removed. Audio files (MP3, M4A, WAV, and others) can be boosted the same way. Those land in Music/PlainLoud.

What a boost cannot do

Turning a file up does not invent detail that the microphone never captured. A voice across a gym gets louder, and so does the room. If the video has more than one sound track, PlainLoud uses the first. There is no account, no ads, no analytics, and no internet permission.

Get PlainLoud on Google Play