eli5 how headphones play some instruments in one ear but not the other

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I’ve questioned how for a very long time, but how do songs from my phone play instruments in one ear but not the other? For example, Stairway to Heaven. The intro plays an acoustic guitar in my left ear but not right and later a wind instrument in my right but not left. Then, Robert Plant in both ears but if I take out one side it’s just Plant and the guitar or Plant with the wind instrument. How?!?!?! This is so sick but how does the phone tell one side to play but not the other?

In: Engineering

5 Answers

Anonymous 0 Comments

That’s a choice by the audio technician that mixed all the studio recording tracks down into the stereo sound you’re playing from a CD or streaming audio service.

Anonymous 0 Comments

This is done in the recording studio during the mixing process

Left and Right are different audio channels in the recording. The recordings of individual Instruments and voice can be panned left or right (or even in surround sound) using a crossfader knob, it’s very easy to do.

This is often done for the feeling of movement it generates. Mixers can make it sound like you are in a room with the band with one player on your left, another on the right, and the singer in the middle.

One classic example is in Tool Albums Danny Carey’s drums are panned in such a way that as he’s playing different drums left to right they are panned that way in the mix so you here the drums sounds move that way in the headphones.

Now that you know about that go listen to a song like 46&2 in cans and pay attention and you’ll here the drums moving from ear to ear

Anonymous 0 Comments

A regular analog headphone plug has 2 rings on it. One for the Left channel, and one for the Right channel. The music file also has left and right channels. So your phone just sends the right channel to each part of the plug, and the plug sends it down the wire to your headphones.

Most music pre-1960s was mono. Only one channel, same sound on all sides. Then we got stereo (2 channels, left and right). And now we have shit like 7.1.4 Dolby Atmos with 7 channels (left front, center, right front, left side surround [Lss], right side surround [Rss], left rear surround [Lrs], and right rear surround [Rrs]), one LFE channel, and 4 overhead channels.

Anonymous 0 Comments

well there are 2 wires. 1 to 1 ear, 1 to the other. They are seperet wires to the phone. that is why the connector has 3 to 4 rings on it, 1 for ground, 1 for each side, (and 1 for the mic).

the phone its self has an audio file with a left and right channel, so it sends one channel to each wire.

Anonymous 0 Comments

> How?!?!?!

Because most every song for the past many decades has been mixed/mastered in stereo (left & right sides).

Some modern music is done in surround sound/Atmos, which is even more amazing.