Fig. 3. The proper Retune Speed control setting is crucial for natural-sounding pitch correction.

With all of the attention these past few years on the Auto-Tune Vocal Effect (the T-Pain/Cher style effect), it’s easy to forget that Auto-Tune was initially designed for natural-sounding pitch correction. However, not everyone takes advantage of the available tools to avoid that “pitch-corrected” sound, so here’s a primer on how to get the most realistic pitch correction.

RETUNE SPEEED
This is the most important parameter for natural pitch correction, as it adjusts the speed at which out-of-tune notes are changed to the “right” notes (Figure 3). The speed should be fast enough to get out-of-tune notes in tune quickly, but not so fast that it sounds unnatural. This is tricky, as the optimum Retune Speed depends on song tempo, note duration, vocal style, etc., and can often change from note to note. Fortunately, Auto-Tune Evo includes tools in both Automatic and Graphical Modes that simplify setting the optimum Retune Speed.

Fig. 4. Use Humanize to make sure both short and sustained notes receive the proper amount of correction.

HUMANIZE
In Automatic Mode, a performance that includes both very short notes and longer sustained notes can be problematic because in order to get the short notes in tune, you have to set a fast Retune Speed, which would then make any sustained notes sound unnaturally static. To solve this problem, use Automatic Mode’s Humanize function.

The Humanize function (Figure 4) differentiates between short and sustained notes, so you can apply a slower Retune Speed just to the sustained notes. This lets those notes retain the natural variations of the original performance.

To adjust Humanize start by setting it to 0, then edit the Retune Speed until the shortest “problem notes” are in tune. If any sustained notes sound unnaturally static, start advancing the Humanize control. Higher settings slow the Retune Speed more for sustained notes. Find the point where the sustained notes are also in tune, but have enough natural variation to sound realistic (if Humanize is too high, any problematic sustained notes may not be fully corrected).

Fig. 5. These buttons represent the three different types of editable objects in Auto-Tune Evo.

INDIVIDUAL CORRECTION OBJECT RETUNE SPEEDS
Prior to Auto-Tune Evo, it was necessary to select a single Graphical Mode Retune Speed that applied to all of your pitch corrections. Your choice was typically picking a Retune Speed that was a “good enough” compromise for an entire track, or painstakingly automating the Retune Speed from phrase to phrase or even note to note.

Auto-Tune Evo allows setting independent Retune Speeds for every individual correction object, whether Line, Curve, or Note (Figure 5); select one or more objects, then set the Retune Speed that provides the most natural result.

Of course, in practice you don’t need to set an individual Retune Speed for every object. To streamline the process, start by selecting all your audio and setting a Retune Speed that works for the majority of the performance. Then listen to the result and note which notes or phrases could still use improvement. Select those notes or phrases, adjust their Retune Speeds for the most natural result, and you’re done.

Fig. 6. You can set useful defaults for the three object types to serve as a point of departure for editing.

DEFAULT GRAPHICAL RETUNE SPEEDS
Auto-Tune Evo lets you set custom default Retune Speeds for each of the three object types: Lines, Curves, and Notes. These initial Retune Speed values (Figure 6) are automatically assigned to each newly created object.

To choose your own default values, just pay attention to what values you most commonly use for the various objects and set those as defaults in Auto-Tune Evo’s Option dialog. Update as necessary.