Creating harmony parts in Logic Pro X is really easy since the addition of the Melodyne-like Flex Pitch feature. In Audio Example 1, I have sung a fairly simple background “ooo” part.
Audio Example 1:
Of course, I could sing a harmony part, but then I have to deal with any pitch imperfections timing inconsistencies, etc. So I will use Flex Pitch instead.
In Pic 1, you see the one track with the one audio file region.
Now you would do the following:
1. Press Command-D to create a duplicate audio track. I then renamed the track.
2. Option-drag the region on the first track to copy it to the second track.
3. Select the second region and use Option-Command-F (or hold the Control key and mouse to choose convert) and convert the region to a new audio file, leaving the first audio file intact when we flex the second one.
It should now look like Pic 2.
4. Either double-click the new audio file or press E to open the editor. If it opens the Audio File editor, make sure that you switch to the Audio Track editor.
5. Click the Flex button (looks like a bow tie) icon and it will default to Flex Time-Slicing, as you see in Pic 3. Not what we want.
6. As you see me doing in Pic 4, switch to Flex Pitch. My vocal looks like Pic 5.
7. You would then press Command-A to select all the notes. In this example, the harmony I want is a simple minor third above and the first note I sang was E above middle C. So with all the notes selected, I grab the first held not and drag it up to G. See Pic 6.
Listen to the result in Audio Example 2:
Houston, we have a problem! We have B flats that should be B naturals and F naturals that should be F#s.
8. If you click on the Bb key in the keyboard it selects the Bbs.
9. All I need to do is drag them up to B natural, then repeat the process for the F naturals to make them F#s. To avoid obvious phasing, I would now perhaps change the amount of vibrato and/or monkey around with the formant settings, as you see in Pic 7 and Pic 8 by selecting the proper control points on the notes.
10. Finally, with all the notes selected, I would drag them just a wee bit to the right.
You can hear the result in Audio Example 3. Not bad!
Audio Example 3:
This technique will also work for guitar solos in thirds. Check out what I have done in Audio Example 4. I think that sounds even better.
Audio Example 4: