Garageband workaround: Tempo change post-recording

I guess it depends more on your creativity than on the tools you use. You could do it all with your webcam using Photo Booth, in one take, but then you wouldn't be able to overlay multiple tracks and the audio/video quality would be bad.

The basic gist of it is: first you have to create a basic track, probably with some kind of metronome, so you can use it as a base for the instruments and vocals (note they always have headphones while recording, so they can listen to the base track). Then, for each instrument, set up a camera to capture the video and a quality microphone to record audio.

You can mix the audio together in GarageBand, and then sync the audio with the video you recorded at the same time using iMovie. It's a lot of work and can take a long time, but there's no "secret" to it.

If you want more "pro" tools you could use Logic Studio for audio and Final Cut for video. But for simple videos, I guess it would be overkill.

I have a similar need when recording Skype calls. My setup is somewhat different, but the fundamentals should work for your setup. Best of all, you can do it without buying any specialized applications. Rogue Amoeba has a great application called Line In that will allow you to pipe your system's inputs to whatever outputs you are available, including Soundflower.

1. Go to System Preferences -> Sound:

   • Select internal mic as your input if that's what you want to use as your second device. Your output is probably headphones if you're recording. Select that.

2. Start Soundflower.

   • Click the menu bar icon. Select Audio Setup from the bottom of the popup menu

3. This will bring up the Audio MIDI setup application. From here, you'll create an "Aggregate Device," which is accomplished by clicking the + icon in the lower-lefthand corner.

   • I've attached a screenshot so you can see how what the Aggregate Device I've setup here looks like. Your USB input should show up in this menu - add it as an input, along with your internal mic. Don't sweat the output part (that's in the next step).
   • Please note that the settings in this screenshot are not meant to be representative of how you should configure this on your machine, and are just for a visual cue.

4. Start Line In:

   • Set your input as the Aggregate Device you created, and pass that as output to Soundflower (2 Ch). When you're recording, you can select "pass thru," which will allow you to monitor the audio. Nice.

5. Finally, fire up Audacity, and make sure Soundflower is selected as the input. This should create a chain that ultimately pipes your inputs into Audacity.

I hope this helps, and good luck!