– How does a single 3.5 mm jack provide stereo sound?


So on my way back home I was listening to music on my bike and I got fascinated by a sound panning from left to right in my earphones. (I was listening Ready or Not by the Fugees). How does a single contact like a 3.5 mm jack provide a stereo sounding effect? How is it able to split the sound between both earphones?

In: Technology

You will notice black bands on the jack. Stereo will have 2 bands, making 3 connections; L, R, and common. Some new headphones with buttons will have extra bands.

There is a separation on the plug end (little black liners that separate the metal segments) these separate segments connect to wires that feed each individual earphone and allows multiple channels from a single plug.

A 3.5 mm jack isn’t a single contact; it’s three. A standard headphone jack can therefore carry three signals. In most that’s left ear, right ear, and ground. You can get 3.5mm jacks with more contacts too, some have 4 or even 5 and so can carry microphone or video data as well as stereo audio.

the jack is isolated and not just one connection. You can see this with dark rings around the jack. the end of the jack is called the tip and is for the left speaker. Then you have an insulating ring which keeps it separated from the other connections. After the insulating ring you have the ring which is for the right speaker. then another insulating ring. after that you have the sleeve which is the ground