Audacity Forum

When combining different files that are at different speeds what is the best/easiest way to make them all sound and play at the same speed so they can be combined into 1 file?

Thank you for your help.

What do you mean?
Do you mean songs with different tempo (bpm) that you want to play at the same tempo?
or do you mean audio files that have different sample rates?
or do you mean something else?

Steve,

Not sure the exact terminology. I have an mp3 file with 2 people doing an interview that was recorded with prettymay while using skype. Then I've got a music file. Combing them onto the same track the interview sounds normal, the music sounds like a half dozen mice who drank a thousand cups of coffee. Would like the 2 files to synch up. Is the easiest way to do it use the "speed" option and just guess/play around with it ?

Hope that provides you with enough information. Thank you.

DoubleB wrote:Combing them onto the same track the interview sounds normal, the music sounds like a half dozen mice who drank a thousand cups of coffee.

There is no need to combine them on the same track, that will happen automatically when you Export. Just Import all your bits of audio, eacj onto its own track, then use the Time Shift tool to drag them left or right so that they start in the appropriate places. You can also use the tracks volume slider to adjust the volume of each track. Then Export the finished audio as a WAV or MP3. Note: it is always a good idea to keep a backup copy in WAV format.

See here to find out about Exporting and why you need to do it: http://audacityteam.org/wiki/index.php? ... ement_Tips

I assume that when you first open or import the music and the interview that they both sound normal until you put them on the same track? If so, then that's because the two bits of audio were recorded at different sample rate, so if you put them on the same track, you will be causing one of them to play at the wrong speed.

You can also use the tracks volume slider to adjust the volume of each track.
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Thanks for your answer Steve, helped a lot! One other question for now: what is the difference between increasing volume using "amplify" as opposed to using the volume slider on each track? Do they accomplish the same thing or have different applications?

DoubleB wrote:what is the difference between increasing volume using "amplify" as opposed to using the volume slider on each track? Do they accomplish the same thing or have different applications?

Well I'm not a programmer, so I can't be 100%, but as far as I can tell, when you use the volume slider it doesn't actually change any of the recorded data - it simply tells Audacity to play the track louder or more quietly. On the other hand, When you apply "Amplify" or "Normalize" it reads the data, amplifies it (by multiplying the value of each sample by the appropriate amount), then that becomes the new data for that track.

So the difference is, that using the slider is non-destructive - you can change it as often as you like, and if you return the slider back to its original position, the audio will still be absolutely the same as the original track - you haven't changed the data at all.

On the other hand, each time you use amplify or normalise, Audacity will process the data and change the data.