I would be surprised if there is a single major release that does not have pitch tuned vocals, even if just a tweak here and there. Some singers are able to exist only because of pitch tuning and killer videos.
In the “old days,” before pitch tuning (circa 2000), vocalists had to hit the notes right with their own vocal chords or find a different career. According to Wikipedia, Auto-Tune was first deployed as an effect on Cher’s 1998 song “Believe.” Once in the hands of producers and engineers, it rapidly proliferated, and is an essential tool in any pro or serious amateur studio.
The Wikipedia entry is a good read, and talks about musicians protesting tuned vocals. Frankly, I would be surprised if anyone protesting has not had some tuning done to smooth out a vocal part they missed.
In my opinion, as with much technology, pitch tuning has diminished the art. A mediocre vocalist can “sing” in perfect pitch. Style supersedes substance. But, pitch tuning is deeply and permanently embedded in music culture. So, like it or not, live with it.
Notwithstanding, I recently gave a presentation on recording techniques, which took me briefly onto the topic of pitch tuning. I decided to put up a blog post because most non-recording musicians do not understand how it works. As an example, I provided the following screen capture to visualize a vocal line as recorded by the singer.
(click on the image for a larger view) The column on the far left shows the perfect-pitch notes (e.g. A, A#, B, B# …). The alternating horizontal bands across the image are the pitches, essentially black and white keys on the piano. Top to bottom is actually a continuous increment in frequencies that is conveniently grouped by the alternating bands (e.g. the center of middle A=440hz, middle C=261.63Hz).
The blobs in the middle are the notes that the singer sang. The fatter they are, the louder they are. Length is the duration of the note.
As you can see, some of the notes sit right in the middle of the band, whereas some straddle between two bands. The notes between bands are the ones which need to be corrected. Correcting them is dead simple — just drag the note to its optimal position. Bazinga – perfect pitch. Its crazy how easy it is.
Plus, you can shorten or lengthen a note, make it louder or softer, smooth out the modulation or quiver, etc. Perfect notes.
The software will allow you to take much more creative liberties with the notes, such as copying and stacking to create harmonies, or resetting to extreme positions, such as full octaves. However, the more extreme you go, the more you introduce residual noise, aka artifacts, which are not desirable.
The technology will improve so as to enable cheap, real-time, zero-latency pitch tuning, i.e. when you sing into the cheap little karaoke box you bought, your pitch will be perfect. Amazing, yes?