Voice over MP3 on an existing MP3 bed

I’ve looked in the FAQ’s and elsewhere and have not found an answer for this topic.

I have a “jingle” that I would like to use as a bed for an ‘on hold’ audio file creation. I also have brief (25-30 sec) audio files of message copy that I would like to lay over (rather than cut into) the existing jingle.

In simple terms I want to lay ad copy on top of a music background and am unclear how to accomplish that. This is definitely not my field of expertise and would appreciate any help you might offer. I’m afraid this is gonna be a stupid question as the answer will likely be an easy one, but I sure can’t figure it out. And my grandpa always said the only stupid question is the one you don’t ask. So I’m asking.

a stupid question as the answer will likely be an easy one

Not so easy if you’ve never met an audio editor before.

There is one fair warning. Never, ever do production in MP3. MP3 always produces sound damage and you may not hear it right away, if you try to create a show with one, you may find the damage doubles in your final show and the damage nails you right to the wall.

There was a podcast version of a popular broadcast radio show that had a leader at the front. “This podcast is brought to you by Squarespace…” and then it sailed right into the radio show. The radio show sounded very, very nice because they got it from the original Broadcast WAV files, but the leader was an old MP3. So what it really sounded like was:

"This [bubble] podcast is [honk] brought to you [gargle] by Squarespace [echo].

I see it doesn’t do that any more, so some producer must have caught on and changed it.

This also kills people trying to download highly compressed music to make an award-winning podcast on the cheap. Good luck with that.


Anyway. Import all your tracks one right after the other (File > Import). Audacity will stack them up vertically and play them all at once. The trick is to use the Time Shift Tool (sideways black arrows) to push each track sooner and later until they appear at the right time, and then the Envelope Tool (two white arrows and bent blue line) to increase or decrease the volume word by word as needed.

I make that sound so easy, but that’s the short narrative version.

When you get it to sound perfect, slice off the end bits you don’t need (drag-select > Delete) and File > Export as WAV. After you get a perfect archival WAV file, then File > Export as MP3 or whatever your final deliverable is. You should also Save a Project. A Project is cool because it will save all your tracks stacked up in place in case you want to move or change something later – but it’s not a sound file. Audacity will not Save a sound file and Projects do not save UNDO.

You could run into troubles with sound overload because basically, Audacity is adding up all your tracks. Open the WAV export in a fresh Audacity and turn on View > Show Clipping. If you have no red lines inside the blue waves, (overload points) you’re good to go.


First of all, thanx for the reply, I THINK I can follow your instructions.

the file format is what I received the original files in so was out of my control. Should I convert before trying this? As for the finished product, I don’t have a preferred format to save in.

As for the rest, I think if I read and re-read 10-12 times I can get through this. :laughing:

This Tutorial http://manual.audacityteam.org/o/man/tutorial_mixing_a_narration_with_background_music.html is at least partially relevant.

You can use Auto Duck: http://manual.audacityteam.org/o/man/auto_duck.html to turn the jingle volume down when the message starts.

Audacity decompresses MP3 to lossless PCM when you import the files. This doesn’t improve the MP3 quality loss, but it means there is no need or point in converting the files before you import them.

If you want to export the audio file as MP3 you will accept that this degrades the file further (because it is a second lossy encoding) but probably it does not matter for a telephone message.

To export as MP3 you will need to add LAME: http://manual.audacityteam.org/o/man/faq_installation_and_plug_ins.html#lame .


I THINK I can follow your instructions.

I did that at a dead run. Signal when you get stuck.
File > Import > point to your first sound file > OK.

I think you can do it Right-Click on the file > Open-With > Audacity and that works, too.

Once you have an MP3, whatever damage it’s going to contain is baked in, and it’s going to stay the same or get worse. Only two options.