Creating single channel sound (left or right) with no audio bleed into the other channel

Question

Noob to sound engineering and not sure if this is a hardware/software query. I am trying to create a audio stream that plays a sound out of just the left channel. Eventually I want to create audio files that play one sound out of the left and another out of the right. I want absolutely no bleeding of audio from one channel the another. I tried to create a wav file with a left channel in audacity. However, my headphones (even though it plays louder on the left earpiece) still feeds in some audio into the right. How can I generate it so that the right is dead silent and the left just has sound. Is this because of the earphones itself? I see this same issue in say even the youtube videos that show the difference between the right and left. Right is louder BUT left still has some sound. Should I split the audio coming out of the computer and attach two different headphones to achieve what I want? I want absolutely no bleeding of audio from one channel the another. Any pointers in the right direction would be appreciated.

Answer 1

This is called crosstalk: the signal on the left channel leaks into the right channel. When you have 2 audio circuits (left and right) close together without being shielded, the electromagnetic fields produced by the circuits influence each other. This can happen anywhere in the analog signal path: in the sound card of your computer, or in the headphones cable.

You can't fix this in the digital realm: your audio file is set up correctly.

Decent-quality audio hardware usually specifies how much crosstalk it produces. This headphones amp for instance:

Crosstalk (15 ohms) -65 dB

which is pretty much inaudible.