How to make several short clips into one long mp3?

I am using CentOS 6.5 and Audacity 2.0.3

I am trying to use audacity with powtoon, I am new to both.

Powtoon does not allow voice-overs for individual slides. You have to make one long voice-over for the entire video.

IMO: this is a serious limitation.

I am hoping to get around this limitation by making several short clips, and putting them together in to one long mp3. I am also hoping for an easy way to do this. Hopefully, I will not have to export, then import, several mp3 clips.

Powtoon slides last a maximum of 20 seconds. Suppose I have the following slides:

An 8 second slide.
A 12 second slide.
A 14 second slide.
A 9 second slide.

I would like to make four audio clips, each clip corresponding to each individual powtoon slide. Then combine the clips into one mp3, which I could import into powtoon.

I would also like to make a noiseless filler clip. For example, let’s suppose the 12 second slide has no voice over. I will still need to fill that space in my mp3. So I would like to be able to make a completely silent 12 second audio clip, which I could combine with the other clips.

I hope I am making sense. I am not sure if I am using the correct terminology.

BTW: I realize that, in the example I gave, it would not be difficult to make one long clip for the entire video. But image if you making a 15 minute lecture with 60 different slides. It would be like making a movie, and putting the sound later. If you made a mistake at 14 minutes, you would have to start all over again.

Noiseless Filler is easy. Generate > Silence.

It’s a little rough following that, probably because you didn’t go for the goal. Once we get the goal, I’m pretty sure any video editor can handle all this before lunch.

Insert Still:

Insert Sound Track:
Shift to location:

You don’t need to worry about gaps because most video editors automatically fill in picture black and silence as needed. The couple that I’ve used also allow voice-overs.

So what is the show that you seem to be trying to make using the most painful way possible.

You can start recording in Audacity with a stopwatch or stopwatch APP and just talk when you need to. You can break it up into clips or changing timing later, although I’m better than even sure this isn’t what you want. I’m also betting you don’t have an actual script.



Thank you for your response. You seem to be well informed about audacity, but I am not sure if you understand powtoon. I certainly did not explain powtoon very well, so I let me elaborate.

PowToon is an online business presentation software tool that allows you to create animated videos. It is supposed to be quick and easy, even for amateurs. Powtoon is supposed to be an alternative to power-point.

With powtoon, you can make animated slides, up to 20 seconds long. Then you can combine these slides into one long video.

Supposedly, powtoon has a feature to allow users to make voice-overs. However:

  1. I have tried this feature on five different browsers - 2 on Linux, and 3 on windows 7, and it does not work, at all, on any of them.

  2. Even if it did work, it would have this serious limitations: you can only make a voice-over for the entire video, not individual slides. I am very sure of this. It is a huge issue with powtoon users. Over 1000 powtoon users have voted this the #1 feature that powtoon need to add.

  3. Another limitation of the powtoon voice-over feature is: you cannot watch the video while you do the voice-over. You would have to note exactly when each sound is to be inserted, then manually add up the seconds, and insert sounds with split-second timing. If anything went wrong, at any point, you would have to start all over. Or, if you wanted to change anything, you would have to do the entire thing all over - you could not change the voice-over for an individual slide.

Because of these limitations, coordinating the voice-over, with the video, is very difficult, if not impossible, with powtoon.

That is why I am trying audacity.

What I would like to do with audacity is: make a series of audio clips to coordinate with powtoon slides. for example, if there are four powtoon slides, I would need four audio clips. Each clip the exact same lengh of time as the powtoon slide. Then I would have to combine these clips into one long mp3, which I could import into the powtoon video.

It is a kludge of a work-around, but it seems to be the best option I have.

I’ve read through that twice and the only actual question I was able to pick out was how to make a file containing 12 seconds of silence:

  1. Open Audacity
  2. “Generate menu > Silence” and set the duration to 12 seconds, then OK.
  3. Export the file.

It would be best to export all of your clips in WAV format, then, assuming that Powtoon requires MP3 format, import all of your snippets into Audacity, put them int the correct order and positions, and export as an MP3 file for uploading to Powtoon.

If you want a more professional “powerpoint like” program, have a look at the “Impress” presentation software in either Open Office or Libre Office.

The desperation method is play the video presentation on the presentation computer and record your voice-over on a second computer or recording device — Zoom, iPhone Personal Recorder, etc. The show then settles down to a straight, plain voice-over job. You can then play both of them in sloppy sync later to see if everything matches, and then commit to the final show, or patch as needed.

But even that is backwards. It’s almost universally agreed that you cut picture to a sound track, not the other way 'round.

Free Sync production or presentation is begging loudly for trouble like the early films did Sound Sync by playing a phono record connected to the same drive as the projector shutter. Fine as long as nothing goes wrong…goes wrong…goes wrong.

I would be looking for another application or technique.

Any reason you can’t do the voice presentation live, like TED talks?


I read through that again and I never did get the goal. What’s the goal? I don’t mean make a slide show. WHY are you making a slide show?



Powtoon is not “pictures.”

Apparently, I am not able to explain what I am trying to do.

I suppose I will audacity for recording. Then mp3wrap, or something, to combine the clips into one long mp3.

Thank again for the responses.

I have no real idea what you are trying to do either, but if you need to import separate audio files into the Audacity project, press F5 on your keyboard then you can drag them along the Timeline and they will be a single MP3 file when you export them (File > Export). Press F1 to go back to Selection Tool.

If you are asking how to record on one track, press the blue Pause button then Pause again to resume recording, or SHIFT-click on the Record button which will start recording from the end of the selected tracks.


FWIW: I kinda, sorta, almost, in a way, got figured out a way to make voice-overs with powtoons.

I made a powtoon about that.

Still difficult however, because you cannot start powtoon, and audacity, at the same time.