Play a sound file slower or faster

Question

How can you play a sound slower or faster? That would be useful for listening carefully one audio passage or to listen fast forward to find a concrete passage.

Is there something with the play sox command that would do this? Alternative simple solutions also welcome.

Solution 1

I find almost half a dozen softwares recommended here.

• Audacity
• MPlayer
• Rubberband
• Play It Slowly
• Ardour
• LMMS
• MuSE
• Rosegarden

Solution 2

I use the ffplay command (the sister of ffmpeg). There are two ways to change the speed of play: tempo and pitch. The former inserts or skips frames (it sounds like "glitches" in the music) but keeps the tone of the sound intact; the latter makes play smoother but affects the pitch.

The following is an example of adjusting the tempo:

# 20% increase, atrim — start to play from 120-th second of the file
$ ffplay -af "atempo=1.2,atrim=120" foo.mp3 

The following is an example of adjusting the pitch (foo.mp3 has the rate 44000):

# 54000/44000 ~+24% pitch up
$ ffplay -af "asetrate=54000" foo.mp3 

ffplay is a very powerful tool; see more at the man page.

Solution 3

Using sox / play

play file.wav   tempo 2    ##to play 2 times faster
play file.wav   tempo 0.5  ## ""             slower

Comments

[Quora Feans]

I'll check these programs. Mplayer, which is command line and won't deform the pitch sounds promising. Audacity would be more for those people willing to convert a file (not my case).

[Quora Feans]

mplayer -af scaletempo -speed 0.6 solo.ogg is what I needed.

[Ramesh]

@QuoraFeans, glad that the link resolved your problem :)

[MatthewRock]

@QuoraFeans Audacity is not for people willing to convert a file - it's for people willing to modify or create music file. That is your case - and Audacity will do the great job. I've used it several times to change both pitch and speed of songs, as well as many different use cases.

[Quora Feans]

@MatthewRock: you are right. Audacity allows all type of processing. Mplayer would be the tool of choice for some simple command line processing.