Free Slowed + Reverb Maker for Any Song

Speed, pitch and length at each setting

At the default 85% speed, a song plays about 2.8 semitones lower, its tempo falls by 15% and it runs about 18% longer. The three always change together, because the whole recording slows at once.

The table shows what each speed does to a typical pop song at 120 BPM (beats per minute) that lasts three minutes, and to the note A4, which sounds at 440 Hz at normal speed. A semitone is the step between two neighboring keys on a piano.

Each 5% step lowers the pitch a little more than the one before, from 0.9 semitones near full speed to 1.2 semitones near 70%. The bottom of the slider changes the character of a voice more than the top.

A 45 rpm single played at 33⅓ rpm runs at 74% speed and drops about 5.2 semitones, close to the 75% row. That is the sound of a record on the wrong turntable speed, and it is a good reference for how far the slow end goes.

Speeds that move a song by whole semitones

Most speeds leave the song between two keys, slightly out of tune with anything at standard pitch. That only matters when you sing or play along, or mix the edit with another track. For those, use a speed from this table, which lands within 8 cents of a whole semitone. A cent is a hundredth of a semitone, too small a gap for most ears to notice.

Why slowed songs sound darker and warmer

Slowing a recording multiplies every frequency in it by the speed, from the lowest bass note to the shimmer of the cymbals. At 80%, the whole mix moves down by a fifth.

The top of the mix loses its sparkle, which is where the warm, dark color of a slowed edit comes from. Bright pop vocals and high synths gain body as they move down, so they tend to slow well. A song that is already dark and bass-heavy has less room to give.

The bottom of the mix moves toward the edge of hearing. Phone and laptop speakers reproduce little below about 80–100 Hz, so a deep bass line can vanish on them after slowing and boom on a large system.

Start from the best copy of the song you have. Many low-bitrate MP3s cut everything above about 16 kHz, and at 80% that ceiling drops to 12.8 kHz, low enough to hear as a dull, muffled top. A WAV, FLAC or high-bitrate file keeps more of the treble the slowdown pulls down.

How much reverb to add

Reverb is the wash of reflections a room adds after a sound stops, and the guide to reverb explains how it works. The amount you add decides how far away the song seems to play.

The reverb control runs from 0 to 100% and starts at 35%. Use the ranges below as starting points and judge by ear, because a sparse ballad takes far more reverb than a dense, loud mix before it sounds washed out.

Reverb builds up fastest on low notes. Slowing a song already moves the bass and kick drum lower, so a bass-heavy track turns muddy at a lower reverb setting than a light acoustic one.

Starting settings for different kinds of songs

These pairs are places to start. Preview the result, then move one control at a time so you can hear what each change does.

To know where a song starts, measure it with the BPM finder and multiply the tempo by the speed. A 140 BPM track at 80% plays at 112 BPM.

Where slowed and reverb came from

The style grew out of chopped and screwed, a hip-hop remix technique that Houston DJ Screw developed in the early 1990s. He slowed records with the pitch control on his turntables, often to 60–70 BPM, and cut them up with repeats, skipped beats and scratches.

In 2017 Slater, a Houston producer who credits DJ Screw as an influence, began posting slowed and reverb versions of popular songs on YouTube. His edits were simpler than chopped and screwed, with the whole song slowed, reverb added and no chops.

The format spread during the 2020 lockdowns through YouTube and TikTok. Many edits were made in free editors such as Audacity, and the Audacity guide to speed, tempo and pitch shows that manual route.

The same year, a viral TikTok presented the slowed sound without crediting chopped and screwed, and some critics called slowed and reverb a gentrified version of the Houston style.

Slowed and reverb, daycore, chopped and screwed and nightcore

To go the other way, faster and higher, use the nightcore maker, which speeds a song up to 140%.

Fixing a muddy or washed-out result

• The bass booms or smears. Slowing moves the bass and kick drum lower, where big speakers boom and small ones lose them. Raise the speed by a few percent or lower the reverb.
• The voice sounds sluggish. Toward the bottom of the range a singer can sound like a different person. Try 85–90% to keep the voice recognizable.
• The words disappear. Reverb fills the gaps between syllables. Halve the reverb amount and preview again.
• The song drags. A slow song slowed further can fall below 70 BPM and lose its pulse. Ballads usually need only 90–95%.
• The edit clashes with another track. Pick a speed from the whole-semitone table so both sit in tune.
• The file is much bigger than the original. WAV is uncompressed, so it is several times the size of an MP3 of the same song, and the slowed version is longer as well.

Taking the slowed version further

The download is a WAV file of the whole song at the new speed, with the reverb applied. Video editors and DAWs (digital audio workstations) open it without conversion.

For a short clip to use in a video or a post, trim the WAV with the MP3 cutter, which takes WAV files too and can fade the clip in and out.

To edit the slowed song in a DAW, set the project tempo to the new BPM so the grid lines up with the beat. A 120 BPM song slowed to 85% sits on a 102 BPM grid.

You can also slow a track inside a DAW with a varispeed or resampling setting and choose every part of the reverb yourself. A reverb plugin with ducking, such as Halo Reverb, turns the reverb down while the vocal sings and lets it swell in the gaps, so the words stay clear under a long tail.