1. Down With Singing Rodents!
Rumor has it that computer software exists that can shift a pop singer's voice if it's not perfectly in tune with the underlying music. This technology has been around for some time.
A Google search quickly confirms this. Products advertise that they can be used to shift singer's recorded voices to create the "classic pitch shift effect," whatever that is, as well as correct "intonation problems" in recorded music where singer is off-key. One software program claims to use to complex mathematical models of sound transmission through the human skull to reduce the "singing rodent" effect supposedly more noticeable in competing products.
Now don't get me wrong. I'm a big fan of Sheryl Crow. She's not only a great artist, but a great (and controversial) cultural icon for the United States photo/article article here). And I'm a great fan of technology. But I intensely dislike singing rodents.
Listening to "The Light in Your Eyes," I could swear that at some point someone's gone in and manipulated the pitch of Sheryl Crow and her backup singers during a fast trill at the end of some of verse lines. (A musical trill is where the music rapidly alters its frequency around a single note to create a pleasing effect.) Probably some sound engineer (perhaps at the behest of some evil recording industry executive, whom we're told don't really understand music artistry) didn't like the way the fast trill sounded naturally, so they figured they could just go in and fix it with the computer.
Now, I have some advice for future recording and software engineers contemplating using computers to do manipulate singers' trills. First off, don't. We're supposed to think that some really talented high school band could have produced the album. That means the singers are professionals who sound superb when singing a fast trill and don't need computer enhancement.
However, if you feel you must tamper with Sheryl's voice, I have suggested changes for your software. When a singer is following a trill on a musical instrument (or another singer), there will be a subconsciously noticeable delay. That's because the singer will need to first hear the new note played on the instrument, or sung by the lead singer, before she can match that note with her own voice. Secondly, and more importantly, you may not have realized this, but a singer's vocal chords are actually wind instruments, not a keyboard. So when a singer does a very fast trill, it's going to sound more like a fast trill on a wind instrument (say a flute) than it will on a keyboard or piano. Wind instruments, unlike keyboards, can produce continuous variations in frequency, and tend to sweep around notes during a fast trill. (Keyboard-like instruments and some computers, on the other hand, are stuck with discrete-sounding notes during a trill.)