Downstep

Downstep is a desktop app for musicians who learn songs by ear. It changes the speed of a song without changing its pitch, and the pitch without changing the speed. Then it repeats the hard part with an A-B loop.

Speed goes from 25% to 200%, and pitch up to 12 semitones up or down, in small steps. Time-stretching uses the open source Bungee library, with no AI involved. Each song keeps its own speed, pitch and loop, and you can save named presets.

The library works offline: you import MP3, M4A, WAV or FLAC files, and you can group songs in playlists. There is a 7-band equalizer with preamp and balance, keyboard shortcuts for playback and the loop, and MP3 export with speed and pitch applied. A backup file holds songs, presets and playlists, and restores on Mac or Windows, so a band can practice on the same versions.

Downstep is free and open source (GPL-3.0), with no account and no ads.