problem with headphone jack

First of all, I'm new on here and to the mpc and would like to give big thanks thus far for all of the help that I've found searching thorough this site. I bought an audio jack about a week ago but can only hear out of one headphone. I've tried three different sets of headphones so it must be the jack, right? I don't know if I got a specific stereo or mono jack but which do I need? thanks

Top one is what a stereo jack/adapter will look like.

hmmm...I have the stereo so getting the mono would fix this problem?

I don't understand your question... The jack you bought, where is it plugged ? What does it have to do with your headphones ?

since my jack to my headphones is too small to fit into the phones output, I have to connect a larger jack to the headphones jack and then into the the phones output. I can only hear out of one headphone when I do this so I was wondering if it was a stereo/mono issue or something.

Ok,

you need a stereo adapter, Metatron72 told you what it should look like.

The other one is mono.

thank you good sir

I've seen 1/8" to 1/4" adapters that are actually mono 1/8" to stereo 1/4", in fact I own a couple -- by mistake. Why these things are made, I do not know. But since you said you already have stereo adapters, I would double check that the 1/8" side is in face stereo as well. If it is--you should be working fine.