Making Tracks: Intelligent Harmonization
Mar 1, 2008 12:00 PM, By Michael Cooper
Electronic Musician
When trying to create a parallel diatonic harmony from a main melody, simple pitch transposition almost never works. That's because the transposition of all notes by the same number of half steps will, in all but the simplest compositions, create at least some nondiatonic notes (notes outside the current key). For example, to create a harmony that consistently uses diatonic sixth intervals relative to the main melody, you'll need to transpose the song's melody by a major sixth on some notes and a minor sixth on others.
Intelligent pitch-shifting moves all notes by the same interval (such as a third or a sixth) but adjusts the transposition amount of individual notes by a half step where needed to keep all transposed notes within a key signature specified by the user. One application of such processing is to create scale-based background harmonies from a lead-vocal track. In this article, I'll show you how to do that using Celemony Melodyne Plugin. To keep things simple, I'll create a single harmony part (see “Step-by-Step Instructions”).
I've Been Duped
Begin by making a duplicate of the lead-vocal track. The duplicate track will be transposed using Melodyne Plugin's pitch tools to become your background-vocal (BV) track. Preserving the original vocal track allows you to hear it and the BV track simultaneously while composing your harmony part.
Delete any regions of unprocessed vocal on the BV track where you are certain you will not want harmony (see Fig. 1). Deleting these areas will prevent Melodyne Plugin from voicing unprocessed audio in those sections, which would cause a doubling effect when played along with the lead-vocal track. Instantiate Melodyne Plugin on the BV track, click on the plug-in's Transfer button, and play back only those portions of the track where you want to generate harmonies. (This loads the original audio into the plug-in for analysis and subsequent processing.)
Now click-and-hold your mouse on the pop-up menu in the lower left corner of the plug-in's window and select Scale Snap. In the Note Ruler, click on the letter corresponding to the key of the song. Shift-click on the letter to toggle between major and minor keys having the same tonic note.
What a Drag
Select the group of Blobs (graphical depictions of notes in Melodyne Plugin) that you want to transpose by a particular musical interval by Shift-clicking on each Blob in turn or dragging over the group with Melodyne Plugin's Main tool. Then click on any one of the selected Blobs with the Pitch tool and drag it up or down by the desired interval. All the other selected Blobs will be moved by the same number of half steps and then will snap to notes belonging to the scale you selected in the Note Ruler.
At this point, you have created a parallel diatonic harmony. You can change certain notes, however, to create a mix of different intervals by dragging their Blobs up or down again in the editor. Melodyne Plugin will make each Blob you move snap to the nearest note that fits your current scale. If you want to move a Blob to a nondiatonic note to create a passing tone or accommodate a temporary modulation into another key, select Note Snap from the pop-up menu in the lower left corner of the plug-in before dragging the note. Doing so will allow you to transpose a Blob chromatically without regard to key signature.
Fine-tuning
Once your harmony part is to your liking throughout the song, you will likely need to apply pitch correction to some Blobs to make them sound more in tune. Double-click on a Blob with the Pitch tool to move it exactly to its pitch center. In the cases when this doesn't sound good, hold down the Alt (PC) or Option (Mac) key while dragging the Blob with the Pitch tool to deactivate the snap function, and then fine-tune the amount of pitch-shift.
Drag down on a Blob with the Pitch Modulation tool to reduce (or completely eliminate) excessive vibrato. You can use the Pitch Drift tool in a similar fashion to prevent sustained notes from gradually sliding off their pitch center. Drag up or down on a Blob with the Pitch Transition tool to adjust the portamento time between two pitches, smoothing out jerky pitch transitions. All these adjustments can make a big difference in how natural your harmony track sounds.
Finally, you can use Melodyne Plugin's Formant control to gender bend the BV track. For example, increasing the formant control will create a female-sounding harmony vocal from a male vocal track. Hey, Bruiser — you go, girl!
EM contributing editor Michael Cooper owns Michael Cooper Recording in Sisters, Oregon. Visit him at www.myspace.com/michaelcooperrecording.
Helpful Resources
Celemony, the creator of Melodyne Plugin
STEP-BY-STEP INSTRUCTIONS
Step 1: Instantiate Melodyne Plugin on a duplicate of the vocal track. Then click on the Transfer button and load the track’s audio into the plug-in by playing it back.
