The tuning context
With its inspector fields, macros and Pitch Ruler, Melodyne supplies you many instruments for bringing an unruly vocal performance – or, rather, its unruly pitch curve – to heel. All such tools reference the Pitch Grid, which (initially, at least) is based on a tempered scale in which A = 440 Hz.
Let’s suppose, however, that the accompaniment to which the singer was listening when laying down the track was provided by an instrument not tuned to 440 Hz or tuned deliberately to something other than a tempered scale. Then Melodyne needs to know all about this alternative tuning; otherwise you will be “flying blind” as you edit the vocals and may fall into the error of supposing that because the changes you are making look right, they must be right.
For this reason, it is advisable to subject the first instrument recorded, which the performers will be hearing later in their headphones as they record the remaining tracks, to a quick analysis in Melodyne. Let’s suppose it was a guitar and that it looked like this in Melodyne:
A right click on the Scale Ruler (1) shows you what Melodyne discovered as it analyzed (2) the track. There you will see two values: the first being the tempered scale to which your guitar comes closest (3) and the second, the actual microtonal scale the guitar was using, including any non-tempered intervals or out-of-tune scale degrees (4).
Now you need to consider what the guitarist’s intention was: Was he intending to play in F Major but either tuned his guitar badly or at times (whether deliberately or accidentally) bent the strings? In that case, select the first option (3).
Or did he deliberately employ an exotic tuning for this recording? In that case, select the second option (4).
The Pitch Grid, based upon the selection you have just made, will now serve as the reference for all the aids we mentioned earlier, such as the Correct Pitch macro, the inspector field and the Pitch Ruler. In this way, you ensure that your vocal editing takes the existing accompaniment into account, and that, if you opt for 100 % pitch correction for the lead vocal, this brings it into 100 % alignment with the guitar – whatever its tuning – rather than with something altogether extraneous.