Elysia Tools
Navigation
Media
Change speed without pitch, or pitch without speed
Details
Uses FFmpeg atempo for time-stretching and asetrate+atempo for pitch shifting.
Execution
Fill in the form, run the tool, and review the result in one place.
Samples
Related
Ready for a run
Tool usage guide
This tool lets you adjust audio speed without changing pitch or shift pitch without altering speed, using FFmpeg's atempo and asetrate filters for precise control.
Background
A user wants to listen to a 90-minute podcast during a 45-minute commute.
Problem
Standard playback is too slow, and speeding up in media players often distorts speech pitch.
How to use
Upload the podcast MP3 file, select 'Time Stretch' mode, set tempo factor to 2.0, and output as MP3.
Outcome
The podcast plays in half the time with clear, natural-sounding voices.
Background
A guitarist needs to practice a song recorded in A major but requires it in F major for easier chord shapes.
Problem
The original key is too high, and manual transposition is error-prone and time-consuming.
How to use
Upload the audio file, choose 'Pitch Shift' mode, set semitones to -4 (from A to F), and output as WAV for high fidelity.
Outcome
The track is shifted down by 4 semitones, making it playable in the desired key without tempo change.
Any audio format supported by FFmpeg, such as MP3, WAV, AAC, OGG, FLAC, and more.
It uses FFmpeg's atempo filter to adjust speed while keeping the original pitch unchanged.
No, the tool handles one audio file per session to maintain processing quality.
Audio files must be under 200 MB.
Tempo factor ranges from 0.25 to 4, and pitch shift from -12 to 12 semitones.
Background
Editing a sports highlight reel with a slow-motion replay that needs matching audio.
Problem
Slowing down the video also slows the audio, lowering the pitch and making it sound unnatural.
How to use
Upload the audio clip, select 'Time Stretch', set tempo factor to 0.5, and output in AAC format for video integration.
{"mode": "time-stretch", "tempoFactor": 0.5, "outputFormat": "aac"}Outcome
Audio is slowed to half speed while preserving the original pitch, ideal for slow-motion effects.