Getting a sound clip ready to use

A voice note for a course, an interview for a podcast, a sound effect for a video: a raw recording usually starts too early, ends abruptly, is too quiet or too loud next to everything else, and carries the name of the phone or app that made it. These tools fix each of those in your browser, without installing an editor or uploading the recording.

1. Cut it to the part you need

Open the recording in the Audio Trimmer. Click the waveform near where the speech starts to move Start, and near where it ends to move End, then Play the result to check you haven’t clipped a word. Add a Fade in and Fade out of 0.3 seconds or so, so it doesn’t start or stop with a click.

Tick Mono for speech: two identical channels double the size and add nothing, and podcast apps play mono to both ears. Save as WAV keeps the full quality for the next steps.

2. Listen with your eyes for hum and noise

Open the WAV under See a sound’s spectrogram in Spectrogram. Speech shows as stacked bands that come and go; anything that runs the whole length as a straight horizontal line is a constant noise: a line at 50 or 60 Hz (with copies at 100, 150… or 120, 180…) is mains hum, and a haze across the top is hiss. These tools don’t remove noise, so if the line is strong, record again away from chargers and fridges, or use a noise reduction tool before the next step.

3. Set the loudness to the platform’s target

Every podcast app, streaming service and broadcaster turns each file up or down to its own loudness, measured in LUFS. A file far off the target gets turned up with its noise, or turned down and sounds flat next to the rest.

Open the clip in the Loudness Meter. Integrated loudness is the figure that counts, and the table compares it with the usual targets: about −16 LUFS for podcasts and Apple, −14 for Spotify and YouTube, −23 for broadcast. Choose the Target and Save at this loudness. If the message says it could only go part of the way because the peaks would go over −1 dBTP, the recording has sharp peaks (a laugh, a cough, a plosive): trim them, or use a limiter in an audio editor, then measure again.

For a course or a set of clips that play one after another, use the same target for all of them, so learners don’t keep reaching for the volume.

4. Take out what it says about you

Open the final file in Audio Tags. A recording can carry the app or software that made it and the date it was made; files that went through a music app may carry cover pictures, comments and the owner’s name. Save without tags saves a copy with the sound unchanged and none of that. Add the title and artist you want in the app you publish with.

WAV files are large. If the platform wants a smaller file, choose AAC .m4a or MP3 beside Save at this loudness in step 3 instead: AAC sounds a little better for its size, and MP3 is accepted everywhere. The small file is made once, from the full-quality sound, at the end, and has no tags to take out; making it first and editing afterwards loses quality twice.