How can most music that’s playing from headphones have separate sounds for each ear?
In: Technology
If you look at the headphone plug it will have little black lines around it… Those lines separate the signal into three pieces… there is a tip… then a ring… then the base of the plug or sheild. One ear gets its audio feed from the tip… the other is from the ring… and finally the shield is a neutral that helps reduce noise.
If the original sound is recorded in mono it will send the same signal over both ear buds.
If somehow you had a mono set of earphones (no ring) and the signal was in stereo… you would recieve the left side audio only over both earbuds.
To play stereo, you need a headphone jack with two rings, that divide the metal connector into 3 sections. Two of those sections correspond to Left and Right.
Some connectors only have one ring – they can only play mono (same sound to both sides). Connectors with 3 rings have a microphone channel too.
In stereo you can send information to one speaker in the left ear and different information in the speaker in the right ear
Think of it conceptually similar to how music is recorded, with each instrument having their own channel (or often more, with the drum kit each drum and cymbal it’s own channel). When the song is mixed, these many input channels are then output to two output channels, a left one and a right one, each with their own volume balance per instrument, creating differences between the channels. Your music player can read this stereo format and then knows which channel to put to which ear, so a guitar solo could end up only on your left ear if the mixer/musician wishes to choose so. I believe most smartphones I believe also have a mono option which levels the two channels equally (or maybe just play one channel on both ears, I don’t know the details).
It’s called the stereo field. Each individual element of a song can have its own position in this stereo field.
When you record music, each element can have its own track. So for a drum kit, for instance, the kick drum goes on one track, snare on another, and Tom’s each on their own track. This allows you to mix the volume levels of each element to create something that sounds nice and balanced, you can pick out what each instrument is playing.
But it doesn’t stop at volume. There is also pan, short for panorama.
This allows you to place an element in a specific place within the stereo image. Turned all the way to the left makes that element only come through the left speaker, all the way to the right means the instrument only comes through the right speaker. Set in the middle means the sound plays equally through both speakers.
You can place things at any point between 100%left and 100% right.
If you place something at, say, 75% left, then 75% of the total volume of that element will come through the left speaker and 25% through the right.
Think of it almost as having two different files/tapes/data-sources for each ear. The speaker for each ear only plays the data for its ear. They mix the recordings differently for each ear in post production so each will get a different sound resulting in the desired effect they’re trying to produce. Then old wired headphones actually had two separate wires for each ear. Wireless will have two different data streams for each ear.
Stereo. The music is recorded with two microphones and the sounds from each are stored separately on different “tracks”. Then they are sent to their respective sides of the headphones. Stereo records were a big deal, the two separate sounds are reflected on their respective sides of the record groove. Now a days it is digitally separated.
We also have things like 7.1 surround sound which are, get it, 8 separate audio tracks all with their own speaker to give the illusion of different things happening in all directions.
It’s not difficult. The audio is recorded or engineered with separate left and right (stereo) channels in mind. The final product is packaged in a storage format/medium that supports stereo sound. The audio player supports reading the stereo sound, and sends 2 separate signals along 2 separate wires that reach 2 separate speakers, for the left and right ears.
Latest Answers