Replayer: Music Slow Downer 4+

Slow Downer for Music Practice

Lukasz Adamczak

    • 3.4 • 9 Ratings
    • $9.99



(fully functional trial with 10-minute usage limit)

Replayer is the simplest audio player for any practicing musician

* Slow down music without changing the pitch
* Zoom in and isolate parts of the file
* Loop selected region of the song
* Adjust pitch to match your instrument's tuning
* Use simple keyboard shortcuts for effortless practice


- Adjust playback speed between 25%-175% without affecting pitch
- Adjust pitch from -2 semitones to +2 semitones
- Playback of any OS X-supported audio file
- Drag and drop of audio files onto the app window
- Drag and drop files from iTunes
- Play only a selected portion of the file
- Automatic looping of the range
- Use mouse scroll wheel to zoom in and out
- One-handed keyboard operation

Keyboard shortcuts:

space - play/pause
return - play from beginning of the range
left arrow - rewind 2 seconds
right arrow - skip forward 2 seconds
+ - increase speed by 5%
- - decrease speed by 5%
0 - reset speed to 100%
] - increase pitch by 1 semitone
[ - decrease pitch by 1 semitone
A - set current range beginning at cursor position
Z - set current range ending at cursor position
X - reset range to entire file
L - toggle looping on/off

What’s New

Version 1.1.4

Version 1.1.4 improves compatibility with macOS Big Sur and user experience for trackpad users.

Ratings and Reviews

3.4 out of 5
9 Ratings

9 Ratings

Katmamajams ,

One flaw . . .

This is just fine for what it does in the moment, but it would be HUGELY more helpful if there was a way to save the slowed down version. I practice with my iPod. It would be so much better to be able to save a file and take it with me to use again and again.

A stupid mark ,

loop doesn’t work

What good is a music trainer if the looper doesn’t work? You can’t keep taking your hands off of your instrument to backup the music for the sections you want to master.
Wouldn’t recommend this to anyone until this gets fixed. Even though the app is pretty self explanatory, some documentation would be nice. You can get versions better than this for free on cell phone apps.
Sorry I wasted the ten bucks!
Come on guys! This could be any easy fix.

Swim'n Bird ,

Could use an update

the interface has some glitches on Sonoma for me, the audio transient view was extremely small in the corner and I had to full screen it then unfull screen it to fix it. good app though

App Privacy

The developer, Lukasz Adamczak, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Up to six family members can use this app with Family Sharing enabled.