Audio editing help needed

macOS and Mac Apps

Hi all,

I've got back into doing radio shows recently and one of them is a weekly pre-recorded show. At the moment the way I'm recording it is by copying and pasting my tracks (MP3 or M4A files) into GarageBand and adjusting the volume of each track accordingly. However, a really serious problem I'm having is I can't fade down music for a few seconds while I talk, and then fade it back up.

For example, if a track has a 20 second intro and I wanted to speak while the intro is playing, I cannot figure out how to select just the first 20 seconds of that track, fade it down so I can be heard over it, and then bring it back up again for the rest of the song. This issue also means I can't use beds as I'm talking, which I'd like to do as it sounds much better with them in my opinion.

I have tried everything I can think of on the latest GarageBand for Mac, and I also played around with Audacity to see if it would do this but have had no joy with either. Could someone give me any idea of how to do this either with GarageBand or any other VO accessible, and preferably free, audio editing software?

Thanks in advance.



Submitted by Remy on Friday, December 1, 2017

There is a way to do it, even in free Audacity. It's called Auto Ducking, and it's one of the FX plugins that comes with Audacity. It's been quite some time since I've used Audacity, having switched to Reaper a long time ago, but this works pretty well. Essentially you set a threshold that specifies when to duck one track while another one comes in, and you can also specify how long it takes to gradually lower the volume and then raise it again, and by how much you reduce the volume. If you google Auto Ducking Audacity you'll certainly find some tutorial. I've used it before and it's very helpful. You just need to make sure you have your tracks laid out in the right order. I do a whole lot of sound design and audio editing and shortcuts like this are standard protocol that saves hours of editing.

Submitted by Remy on Friday, December 1, 2017

I should mention also that Audacity does allow for some automation of volume and panning using envelopes. Essentially you set a point on your track, then a slope specifying how high or low you want the volume to raise, and how gradually, and then you put another point. Continuing this allows you to have the track's volume raise and lower at pe-determined points. Only thing is, the base envelope tool is not accessible in Audacity as far as I know. There is however a plug-in you can get that will work. I can't remember what it's called, but if you look up audacity envelope accessibility you should find it.

Submitted by Callum on Friday, December 1, 2017


Thanks so much for your reply. I've just given the auto ducking feature a go but I'm having some trouble with it. This week I'm doing an hour long continuous mix which I've done in DJay Pro, and I've imported that into my audacity project as one long track. Currently, the way I'm recording my speech is to make a selection at where I want my speech to start, ending the selection at where I want to stop speaking, and just recording from those two points. This way, all my individual speaking parts go in as separate tracks.

When it comes to auto ducking the music so my voice can be heard, I make sure only the track with the mix is selected, and all my individual speaking tracks are unselected, then apply the auto ducking effect. However, this only ducks the track on my first speaking part. The rest of the time when I talk the volume of the music stays the same. Any idea what I'm doing wrong?

Thanks so much and sorry if this is a bit complicated.