Is there an easy way to slow down an mp3 that is too fast?

[kschwi]

I have several mp3 recordings that have been converted from cassette that sound like the recording is playinig too fast and the voices are a bit squeaky or heilum like. It is not super fast but noticeable and irritating. I would guess the person who did the conversion must have has his cassette player play the tape a bit too fast. I do have audacity. Does it have the ability to slow down the speed of the recording a bit? There are voice recordings (sports broadcasts) and not music if that makes any difference.

[smartel]

http://bestpractice.sourceforge.net/

[johns0]

In audacity look in the top tab bar for effect and change speed,use a value of -5% to start.

[kschwi]

In audacity look in the top tab bar for effect and change speed,use a value of -5% to start.

Ok, I loaded the file in Audacity and then moved the bar in the upper right hand corner and adjusted it to 97x. The next setting looked like 93x which seemed too slow but didn't see a setting in between.

IF I settle on the 97x speed setting how do I save the entire recording at that speed?

[johns0]

File/export but dont use 97,use -5 as i suggested,its a % value and 97 will be way too fast,use the - to make it slower.

[jimdagys]

You could try the very easy to use software called Transcribe to change pitch/speed. Not free software, though.
http://www.seventhstring.com/xscribe/overview.html

[AlanHK]

...

[pandy]

Set slower playrate and if it suit Your subjective expectations resample to some common sampling frequency.

For Audition this is option Adjust Sample Rate (put something lower than current) if it works, then perform Convert Sample Type to for example 44100 or 48000.

Same operations can be performed by SOX (which i recommend due probably higher overall quality for processing)

sox -r 33333.0 inputfile.wav outputfile.wav rate -v -I 44100.0

[dfisher052]

Try Goldwave...not free, but is an excellent editor. You can listen to the change in pitch before you save it.

[kschwi]

File/export but dont use 97,use -5 as i suggested,its a % value and 97 will be way too fast,use the - to make it slower.

The 5% sounded good when I clicked the green arrow in the upper right hand corner, but when I used File export it didn't sound like it applied the 5% to the recording. Is there something I need to do before I click file export? I might think I need to do something to tell it to apply it to the entire mp3 file.

[sambat]

As noted in a previous post, on the top menu, click 'Effect' > 'Change speed' and insert a negative number to slow it down.
You will see the length of the stream change if it takes effect.
That button you are using only adjusts the playback speed locally - not the exported audio.

[kschwi]

Ok, I see it now. Thanks.

It works pretty well but I wish there was a longer preview.

[AlanHK]

Ok, I see it now. Thanks.

It works pretty well but I wish there was a longer preview.

Preferences/Playback/Length of preview

[smartel]

give bestpractice a try , simplest thing . post 2

[kschwi]

File/export but dont use 97,use -5 as i suggested,its a % value and 97 will be way too fast,use the - to make it slower.

It has been working pretty good. Here is something odd. I used 3.5 to speed up something I thought was too slow and the length of time on the recording is slightly shorter instead of longer. Did I do something wrong?

[johns0]

If you speed up the audio the duration will be shorter.

[Cornucopia]

Note that doing any of these kinds of conversions will result in some loss of quality (plus more loss if you re-encode to mp3 or similar lossy codec).

Scott

[kschwi]

Note that doing any of these kinds of conversions will result in some loss of quality (plus more loss if you re-encode to mp3 or similar lossy codec).

Scott

It's not a big loss is it for voice only recordings? Listening to Dodger's broadcaster Vin Scully as if he is on helium is not fun so I really don't have a choice.

[Cornucopia]

The loss in quality greatly depends on these things:

• The richness/complexity/dynamics of the source signal (classical music vs. rock music vs. sound effect vs. voice, etc)
• The algorithm(s) involved in the app doing the sample/tempo/pitch/formant conversion.
• The algorithm & bitrate chosen for the lossy final codec.
• The greatness in the amount of change to the signal (.1% vs. 4% vs. 15% vs. 50%)

With the right algorithm/app, with a change of say <~25%, and with a high enough final mp3 bitrate, the quality will probably be acceptable, even if noticeable.

Scott