What is Panning?
Panning in audio borrows its name from panning action in moving image technology. An audio pan pot can be used in a mix to create the impression that a source is moving from one side of the soundstage to the other. Although ideally there would be timing (including phase and Doppler effects), filtering and reverberation differences present. This complete the picture of apparent movement within a defined space. Simple analog pan controls only change relative level; they don’t add reverb to replace direct signal, phase changes, modify the spectrum or change delay timing. “Tracks thus seem to move in the direction that [one] point[s] the pan pots on a mixer, even though [one] actually attenuate[s] those tracks on the opposite side of the horizontal plane.
Panning represents a distribution of a sound signal (either monaural or stereophonic pairs) into a new stereo or multi-channel sound field determined by a pan control setting. A typical physical recording console has a pan control for each incoming source channel. A pan control or pan pot (short for “panning potentiometer”) is an analog control with a position indicator which can range continuously from the 7 o’clock when fully left to the 5 o’clock position fully right. Audio mixing software replaces pan pots with on-screen virtual knobs or sliders which function like their physical counterparts.
Back in the day
Before pan pots were available, “a three-way switch was used to assign the track to the left output, right output, or both (the center)”. The Billboard charts throughout the middle and late 1960s were full of this. Clear examples include the Beatles “Strawberry Fields Forever” and Jimi Hendrix’s “Purple Haze”. In the Beatles’s “A Day In The Life” Lennon’s vocals are switched to the extreme right on the first two strophes. On the third strophe, they are switched center then extreme left. On the final strophe, they are left. What’s more, during the bridge McCartney’s vocals are switched extreme right.
Manipulation tracks in the stereo spectrum through the use of panning is one of the principal ways for creating a wide stereo mix. Many engineers when they are starting out make the mistake of recording everything in stereo. They think this will create a wide mix. This is a mistake. However, because everything is recorded in stereo, and panned hard left and right, the sound completely occupies the center of the stereo spectrum. If you listen to commercial recordings, you will hear that most of the audio tracks are coming across from mono and panned in the particular location in the stereo spectrum. If some instrument is in stereo, don’t be afraid to either eliminate one of the sides of the recording. Also, try to pan both tracks in a single mono position.
Certain instruments, such as an acoustic guitar, piano or some electric guitars work well as a stereo instrument. The style of music mainly determines this. If the focus of a song is on acoustic guitar, then it most likely it should remain a stereo instrument. Moreover, if the acoustic guitar is the rhythm instrument, it may be better to have a doubled mono track as opposed to a single stereo track. This gives the engineer the ability to hardpan both mono acoustic tracks. At the same time, it lives a hole in the center for the other focal instruments.
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