How to Use Music Slow Downer

Published October 28, 2026 • 9 min read

Music Slow Downer is a free practice tool that runs entirely in your browser. It slows audio without changing pitch, shifts pitch without changing speed, loops any section, filters the sound to bring a frequency range forward, and exports loops as WAV files. This guide covers every control in the order you'll use them, then a practice routine and troubleshooting.

No account or installation is needed. A desktop or laptop with Chrome, Edge or Firefox works best; phones and tablets work with some limitations.

1. Loading Audio

From a file on your device

1. Open the tool page.
2. Click Choose audio… and pick a file, or drag a file from your desktop onto the Drop file here area.
3. The file name appears and the waveform is drawn; the controls become active.

Any format your browser can decode works — MP3, WAV, M4A, OGG and FLAC in most desktop browsers. The file is decoded in memory and never uploaded.

From another browser tab

If the music you want to practise is playing in another tab — a lesson video or a streaming site — you can capture it. This works best in desktop Chrome or Edge.

1. Open the source in another tab and pause it at the point you want to start.
2. In Music Slow Downer, click 🎵 Record Tab Audio.
3. Your browser shows a sharing dialog. Choose the tab (not a window or the whole screen) containing the audio.
4. Make sure the Share audio (or "Also share tab audio") checkbox is ticked. Without it, the recording is silent.
5. Click Share, switch to that tab and press play. Let it run through the section you need, plus a few seconds either side.
6. Come back and click ⏹ Stop & Load. The capture is loaded into the player like a normal file.

Recording happens in real time, so capture only the section you need plus a few seconds. Respect the source site's terms and keep recordings for personal practice.

2. Playback and the Waveform

• ▶ Play starts and pauses playback (or press Space).
• ⏮ jumps back to the start of the track.
• Click anywhere on the waveform to jump to that point. The readout below the loop buttons shows the current position (Pos) and total duration (Dur).

The waveform is also your map: choruses look taller and denser, intros and breakdowns thinner, and regular drum spikes help you find bar lines.

3. Speed Control

The Speed slider runs from 0.25× to 1.5× in steps of 0.01, and pitch is preserved at every setting. The current value is shown next to the slider, and the ⟲ button resets it to 1.00×.

To find the resulting tempo, multiply the song's BPM by the speed: a 140 BPM song at 0.70× plays at 98 BPM. To practise a 180 BPM song at 120 BPM, divide 120 by 180 to get 0.67×. Recommended starting points:

• 0.85–0.95×: polishing a part you can almost play.
• 0.70–0.80×: learning a new section or checking a transcription. Sounds natural.
• 0.50–0.65×: fast riffs, ornamented vocals, drum fills.
• 0.25–0.45×: very fast runs, for identifying notes only.
• 1.05–1.20×: overspeed practice, so the real tempo feels comfortable afterwards.

Below about 0.5× you'll hear some smearing and a metallic tone; that is normal for pitch-preserving slow-down (see Troubleshooting).

4. Pitch Shift

The Pitch Shift slider moves the audio from −12 to +12 semitones in whole-semitone steps (no fine-tuning in cents), without changing speed. The ⟲ button returns it to 0. Common uses:

• Down-tuned guitar recordings. If a band tunes to E♭, set +1 to play along in standard tuning; for D standard, +2.
• Singers. If the melody sits too high, try −2 or −3.
• Transposing instruments. Shift to the key you need to read or play in.
• Hearing a part an octave away. +12 lifts a bass line into a range that's easier to hear on small speakers.

Shifts beyond about ±5 semitones sound noticeably unnatural, but the notes remain correct for practice. See why changing pitch can improve your practice for more ideas.

5. Frequency Isolation

The 🎛 Frequency Isolation panel is a band-pass filter: it cuts everything below the Low Cut and above the High Cut. It is not AI stem separation. It emphasises a frequency range, so the instrument you want becomes more prominent, but anything else in that same range remains audible.

For finer control, use the Low Cut (20–2000 Hz) and High Cut (500–20,000 Hz) sliders. For a high guitar solo over a busy band, start from the Guitar preset and raise Low Cut to around 500–700 Hz to remove bass and much of the rhythm guitar's body. The panel's ⟲ button resets to full range.

Tip: narrower is not always better. A band that's too tight makes everything sound thin and telephone-like, which can make pitches harder to identify. Start with a preset and narrow gradually.

6. A/B Looping

1. Play the track. Just before the section starts, press [ set A (or the [ key).
2. At the end of the section, press ] set B (or ]).
3. Press Loop: OFF to switch it to Loop: ON (or press L). Playback now repeats between A and B.
4. Press Clear to remove the markers.

The A and B times appear in the readout. Set A slightly early so you hear the pickup into the phrase; 1–4 bar loops work best for learning. More in Master Any Song Section with A/B Looping.

7. Saving and Recalling Loops

Once a loop is set up, click 💾 Save Loop and give it a name such as "Verse riff – 0.70×". The preset stores the loop times, speed and pitch, but not the audio, so load the same file again before recalling it on a later visit. Click 📂 Saved Loops to see your list and recall one.

Saved loops live in your browser's local storage: they persist between visits on the same browser and device, but not across devices, and clearing browsing data removes them. Include song, section and speed in each name to track progress.

8. Exporting a Loop as WAV

With A and B set, click ⬇ Export Loop. The looped section is rendered at the current speed and pitch and downloaded as a WAV file, ready to copy to your phone, import into a DAW or send to a bandmate. WAV is uncompressed (about 10 MB per minute at CD quality), so a 20-second loop is only a few megabytes.

Keyboard Shortcuts

A Complete Practice Workflow

A typical 20–30 minute session:

1. Load the song from a file or a tab.
2. Find the section by clicking around the waveform.
3. Loop it. Set A and B around 1–4 bars and turn the loop on.
4. Slow it to a speed where you can play it cleanly three times in a row. For a 160 BPM riff that might be 0.60× (about 96 BPM).
5. Ladder up. After three clean repetitions, add 0.05×; after a mistake, drop back 0.05×.
6. Save the loop with your highest clean speed in the name.
7. Export it if you want to practise away from the computer.
8. Finish at full speed: widen the loop and play along at 1.00×, even if not yet perfect.

The tempo ladder method is covered in depth in Build Speed with Tempo Ladders.

Troubleshooting

My file won't load

• The browser may not decode that format; convert to MP3 or WAV, or try another browser (M4A and FLAC support varies).
• DRM-protected files (some purchased or streaming downloads) can't be decoded by browsers.
• Very long files use a lot of memory once decoded; trim to the song you need.

Tab recording is silent or fails

• Check that Share audio was ticked in the sharing dialog. This is the most common cause.
• Share a tab, not a window or full screen, and make sure it is playing and not muted.
• Use desktop Chrome or Edge; other browsers and mobile devices may not support tab audio capture.
• If you dismissed the permission prompt, click Record Tab Audio again.

The audio sounds watery or metallic

This time-stretching artifact is worst below about 0.5×, and large pitch shifts add to it. Use the slowest speeds only to identify notes, then practise at 0.7× or above. A very tight filter band can make it sound worse, so widen it.

Hotkeys don't work

A slider or input probably has focus. Click on an empty part of the page and try again.

My saved loops disappeared

They are stored in your browser only. Clearing site data, using a private window, or switching browser or device means they won't be there.

Problems on mobile

File loading, speed, pitch and looping work in modern mobile browsers, but tab recording generally isn't available, shortcuts need a hardware keyboard, precise waveform clicks are harder on small screens, and long files can exceed available memory. Use a desktop or laptop for serious sessions.

Privacy

All processing — decoding, slow-down, pitch shifting, filtering and export — happens on your device. Files and tab recordings are never uploaded. Saved loops are stored in your browser's local storage and contain only the loop name, times, speed, pitch and the audio file's name — not the audio itself. You can read more in our privacy policy.