Add Reverb and Echo to Audio

How to add reverb to audio with this tool

Reverb is the sound of a space. When you clap in an empty hall, the clap is followed by a wash of thousands of reflections that fade away over a couple of seconds. A recording made in a padded booth or straight into a laptop has none of that, so it sounds close, dry and slightly flat. Adding reverb gives the sound a place to live.

WaveTinker creates the space with a generated room impulse and blends it with your original audio. The important point is that the dry sound stays in the mix. The Reverb knob sets only how much of the reflected sound is added on top, running from 0 to 100 percent and starting at 35. At 0 you hear your file unchanged, and as you raise it the tail grows around the original instead of replacing it.

The second control, Decay time, decides how long the tail takes to fade, from 0.3 to 6 seconds, starting at 2.2. Short values suggest a small room, long ones a church or a canyon. Together these two knobs cover most of what people mean when they say they want to add reverb to a song, a voice recording or a beat.

Presets and what each one is for

Six presets set all four knobs at once. Small room is a tight, short tail that lends a vocal or acoustic guitar a little air without making it sound distant. Hall is the all-rounder: a decay of a couple of seconds that flatters piano, strings and ballads. Cathedral stretches the tail much longer, which suits slow, sparse music, choirs and ambient pads, and tends to blur anything fast.

Slapback echo, Echo and Canyon lean on the repeat control. Slapback echo is built around a short delay, the kind of single quick repeat associated with 1950s rockabilly vocals and guitar. Echo spreads the repeats further apart for a roomy, dub-like effect. Canyon is the big, wide one, the sound of shouting across a gorge.

Presets are only starting points, so move anything afterwards. The preview updates about a quarter of a second after each change, which makes it practical to hold the track playing and lower the Reverb knob until the effect supports the sound rather than covering it. If a preset almost fits, nudge the Decay time knob first, since the tail length shapes the character more than the amount does.

Decay time and typical rooms

The first table in the Numbers tab gives typical decay times, measured as RT60: the time a sound takes to fall by 60 decibels after it stops. A small treated room sits at 0.2 to 0.4 seconds, a living room at 0.4 to 0.8, a classroom around a second, a concert hall near two, and a big church can run from 3 to 8 seconds. These are published ranges, and real spaces vary with size and surfaces.

Use them as a map for the Decay time knob. For speech or a podcast, stay between 0.3 and 0.8 seconds, so words stay clear. For pop vocals, try 1 to 2 seconds. For orchestral or piano music, 2 to 3 seconds sounds natural. Beyond 4 seconds, you are in effects territory: dreamy, huge and not subtle.

The relationship between tempo and decay matters as much as the number. A long tail on a fast track piles up and turns the mix into a smear, because the next note arrives before the last reflection has faded. If the result sounds muddy, shorten the decay before you reduce the amount. A slow song can carry far more tail than a busy drum pattern can.

Reverb versus echo

People use the two words loosely, but they are different effects. Reverb is a dense cloud of reflections that blend together, so you cannot pick out individual repeats. An echo is a distinct copy of the sound that comes back after a delay, and you can count the repeats. A canyon produces echoes because the walls are far enough away for the reflection to arrive as a separate event; a bathroom produces reverb because the reflections come too quickly to separate.

Both live on this page. The Echo knob runs from 0 to 85 percent and starts at zero, so nothing repeats unless you ask for it. It sets both how loud the repeats are and how strongly they feed back into themselves, which controls how many are audible before they sink away. Echo delay runs from 50 to 1500 milliseconds and starts at 350, and sets the gap between one copy and the next.

Mixing the two is common. A short echo followed by a hall tail is the classic way to make a lead vocal stand out. Keep both the echo and the reverb modest on a lead vocal, or the words smear.

Echo times that land on the beat

The second table in the Numbers tab converts tempo into delay times. The reason it exists is that an echo sounds tidy when its repeats fall on the rhythm, and sloppy when they land between beats. At 120 BPM a quarter note lasts 500 milliseconds, a dotted eighth is 375 milliseconds, an eighth is 250 and a sixteenth is 125. At 90 BPM the same notes are 667, 500, 333 and 167 milliseconds.

If you know the tempo of your track, type the nearest value into Echo delay. A dotted eighth is the favorite of guitarists and producers, because the repeats fall between the main beats and fill gaps without fighting the groove. A plain quarter-note delay is steadier and works on sparse parts such as a vocal line with room around it.

If you do not know the tempo, the BPM finder will tell you, and the tap tempo page lets you tap it out. Set the delay and then listen: when the repeats feel part of the rhythm and the pulse seems to lean forward instead of dragging, you have the number.

Settings for typical jobs

A vocal recorded in a quiet room, to sound less dry: Small room preset, Reverb at 20 to 30 percent. Raise it only until the dryness disappears.

A piano or acoustic guitar piece: Hall preset, Reverb around 30 to 40 percent, decay 2 seconds. Add nothing to the echo.

A slow ambient or choir recording: Cathedral preset, decay of 4 to 5 seconds, Reverb at 40 to 50 percent.

A lo-fi beat or a moody edit for a short video: Hall preset with the Reverb a bit higher than you would for a song, since the effect is the point. Try the Echo at 15 to 25 percent with a dotted eighth delay.

Speech that needs a sense of place, such as a narrator in a stone corridor: Small room or a custom decay near 0.8 seconds, Reverb at 15 percent. Heavy reverb on speech quickly destroys clarity.

For a reverse swell before a vocal line, reverse the clip on the reverse page, add a long reverb here, save the result and reverse it once more; the tail now builds up into the original sound instead of fading after it. The studio on the home page has a Reverse reverb recipe that chains the same three steps in one go.

Common mistakes

Too much of it is the usual error. The effect feels pleasant while you are listening to the track alone and ruinous once it sits next to others, because reverb pushes a sound back in the stereo picture. If the vocal now sounds like it is behind the band, lower the amount.

Reverb on everything is another. In a finished mix, adding a wash to a file that already has reverb stacks the tails and clouds the result. Check the Original first. If it already sounds spacious, a light touch is enough.

Last, remember that reverb adds energy to the signal. A strong 100 percent setting pushes the mix toward full scale; the limiter at the end holds peaks at -1 dBFS, so heavy settings sound squashed rather than clipped. The tool also adds the tail to the end of the file, so the whole decay is saved (silence at the very end is trimmed).

Keep playback at a comfortable level while you work, especially on headphones; long reverb tails invite turning things up, and sustained loud listening can harm hearing.

Formats, saving and privacy

The page opens MP3, WAV, M4A and AAC, OGG and Opus or FLAC files up to 250 MB, as long as the browser can decode them. It cannot fetch songs from streaming services, so to treat a track from one of them you need an audio file you own or have the right to edit. Save as MP3 at 128, 192, 256 or 320 kbps, or as WAV with 16 or 24 bits; the expected size appears first. The sound track of most MP4, MOV and WebM videos opens here as well, which suits a dry voice-over; the output is an MP3 or WAV.

Reverb tails contain soft, detailed sound, which low-bitrate MP3 encoding can roughen, so pick 256 or 320 kbps for music and use 128 for talk. WAV keeps everything.

Processing is done on your device by the tab you have open. The file does not travel anywhere, and when you close the page the working copy is gone. The Copy settings link button saves your knob positions in the address for sharing.