I hope you know something about this. I took out a song (from the 70's) by ear with the help of a pinao teacher. I went home and tried to play along with the specific song. I played it in the right key but there was a strange thing on the recording. It sounded like the pitch was a little bit of. The name of the song is Rocking all over the world. It seems like sometime when people record a song they do something to the recording which changes the pitch a little. What could have happened and is this common today? Does pitch change on recordings?
Good morning Andrew-
What you experienced is fairly normal. It could be a couple of things. First, often times musicians tune their instruments specific to the environment, for example, I have a very very old Steinway & Sons baby Grand Piano, and it was made in 1876, so it has to be tuned a bit lower, at A432, instead of A440. This is to prevent the soundboard from bending and warping. Therefore every instrument used next to it must be tuned lower as well. At 8 cents difference it's just enough to sound slightly out of tune played next to regularly tuned instruments. Some people believe there is something "magical" about the A 432
Another option is that the playback speed was changed in the recording process, which often happened in mastering. This might have been a slight speed up, done by the A&R people, "to make the record snappier". They often do this, and while it raises the tempo, it also raises the pitch. This trick is still employed by the way, because sometimes a great record "just drags a little bit", so they bump it up. I wouldn't recommend doing this with digital means, it doesn't sound as good as Tape speed increase.
Lastly, Prince (the Purple one) often employed a similar trick while recording, to change the texture and pitch of his Voice. In fact, for records like "Kiss", he would slow down the playback of the Tape Machine (probably a Studer 24 track 2inch or similar), so that the tempo and key were lowered. Then he would record his Vocal in singing to match the new tempo and pitch. When sped back to normal, he would feel like he was singing a bit snappier and his pitch was raised. This is how the "You don't have to be beautiful..." line is both so high, and so choppy... cool stuff.
Lastly, when it comes to Vinyl and Tape, they had a hard time mechanically staying perfectly "in time" on playback, due to a few things, mechanical in nature, and because of the tension of the tape, on the tape heads, like a bicycle chain, has some play in it... in fact more so since tape can stretch a bit. This is called "Wow and Flutter" which you can Google for more information, but also brought rise to a cool effect called "Tape Phase", which is also worth a Google, used as an effect on a specific track, to give a very cool psychedelic vibe, like a phaser peddle, but unique. We still use this in small doses to make a mono track sound wider (as a stereo effect).
Hope this helps.
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