Slowed & Reverb Studio – Create Aesthetic Slowed + Reverb Music Online Free

About Slowed & Reverb Studio

Slowed & Reverb Studio is a web-based audio effects tool that lets you upload one or multiple audio files, adjust effect sliders (Speed, Reverb, Pitch, Bass), preview the effect on a sample playback, then process and download your edited audio as high-quality MP3 files.

This tool is built to make “slowed & reverb” style edits easy through a simple interface: upload → tweak sliders → preview → apply → download.

What Is “Slowed & Reverb”?

“Slowed & Reverb” typically refers to an audio style where:

• the audio is played at a slower speed (to change the feel and pacing), and

• a reverb/echo-like effect is added to create a more spacious sound.

In this studio, you can control not only speed and reverb but also pitch shift and bass boost using sliders.

Supported Audio Formats

When uploading, the backend validates file extensions and accepts:

• MP3

• WAV

• M4A

• FLAC

• OGG

• AAC

If a file type is not supported, the upload returns an error.

Key Features

1) Upload Multiple Audio Files

• Upload more than one file at once.

• Drag & drop support through the drop zone.

• “Select Files” button to browse and choose files.

2) Audio Effects Studio (4 controls)

The effects you can apply:

• Speed Control (time stretching)

• Reverb Level (echo/reverb effect)

• Pitch Shift (raise/lower pitch)

• Bass Boost (boost low frequencies)

3) Preview Effects (Play Processed Audio)

• Preview is available after at least one file is uploaded.

• Preview processes the first uploaded file with your current slider settings and plays it in the browser.

4) Apply Effects to All Uploaded Files

• Clicking Apply Effects processes every uploaded file using the current settings.

5) High Quality MP3 Output

• Output is exported as MP3 at 320kbps.

• Processed filename uses this pattern:

  • originalName_processed.mp3

6) Download Options

• Download a single processed file

• Download multiple processed files as a ZIP

7) File Management

• Remove individual uploaded files (X icon).

• Clear all files + reset sliders.

8) Temporary Storage With Auto Cleanup

• The system runs an automatic cleanup that removes temp/processed files older than 1 hour.

Audio Effects You Can Apply

Speed Control

• Controlled by the Speed slider.

• Range shown in UI: 50% to 200%

• Internally converted into a speed factor (value / 100).

• Applied using time stretching (librosa.effects.time_stretch).

Reverb Level

• Controlled by the Reverb slider (0–100%).

• Applied using an FFmpeg audio filter (aecho) when reverb > 0.

Pitch Shift

• Controlled by the Pitch slider (-12 to +12).

• Applied using librosa.effects.pitch_shift.

Bass Boost

• Controlled by the Bass slider (0–100%).

• Implemented using FFT and boosting low frequencies.

Output Details

After processing, each file returns details shown in the results list:

• Processed name (e.g., song_processed.mp3)

• File size

• Duration (seconds)

• Format: MP3

• Quality: High (320kbps)

• Which effects were applied (speed/reverb/pitch/bass)

How to Use Slowed & Reverb Studio (Step-by-Step)

Step 1: Upload Your Audio Files

You can upload files in two ways:

Option A: Drag & Drop

1. Drag your audio files from your computer

2. Drop them inside the upload box (“Upload Your Audio Files”)

Option B: Select Files Button

1. Click Select Files

2. Choose one or multiple audio files

3. Upload begins automatically

After upload:

• Your uploaded files appear in a list with:

  • file name (auto-truncated on small screens)

  • file size

  • remove button (X)

• The Preview Effects button becomes enabled if at least one file is uploaded.

Step 2: Adjust the Audio Effect Sliders

In the “Audio Effects Studio” section you can adjust:

• Speed Control (default 100%)

• Reverb Level (default 0%)

• Pitch Shift (default 0)

• Bass Boost (default 0%)

As you move sliders, the value labels update in real time:

• Speed shows 100%, 75%, etc.

• Pitch shows -2, +3 (with plus sign for positive values)

Step 3: Preview Effects (Optional)

1. Click Preview Effects

2. The tool will process the first uploaded file using your current slider settings

3. It will automatically start playing the preview audio

To stop preview:

• Click Stop Preview

• Preview also stops automatically when audio finishes playing

Step 4: Apply Effects to All Files

1. Click Apply Effects

2. The tool sends all uploaded files to the processing endpoint

3. Each file is processed with the current settings

4. Results section appears with processed file entries

The processed list shows:

• file name

• file size

• duration

• quality/format badges

• effect badges (only for effects you used)

• download button per file

Step 5: Download Your Processed Audio

Download Single File

• Click Download on a specific processed item
  This triggers download of that file.

Download All Processed Files

• Click Download Audio (top right in results section)

Behavior:

• If only 1 valid file exists → downloads that single MP3

• If multiple valid files exist → downloads a ZIP containing all processed MP3 files

Step 6: Remove Files or Clear Everything

Remove one uploaded file

• Click the X next to the file

• Tool deletes it from server storage and removes it from the list

Clear All

• Click Clear All

• Removes uploaded + processed files

• Resets sliders to default

• Hides results

Temporary Storage & Cleanup Notes

This tool stores:

• uploaded files in a temp folder

• processed files in a processed folder

A background cleanup job runs regularly and removes files older than 1 hour, so:

• if you wait too long, a file may become unavailable to download

• in that case the tool will show “File not found. Please re-upload the file.”