I was just wondering if there was an adapter that converts

this - http://img18.imageshack.us/i/photoon20100424at1509.jpg/
(that usually goes into this a socket thing like this - http://img704.imageshack.us/i/photoo...424at1510.jpg/)

into this - http://img218.imageshack.us/i/photoo...424at1511.jpg/
(that will go into this - http://img541.imageshack.us/i/photoo...24at15112.jpg/)

At the moment i have just done a little wiring job but its a bit sketchy...... essentially what im doing is plugging in some decent speakers into a sub woofer (i think thats what its called) from a set of computer speakers i got and i was wondering if there was some kind of adapter

thanks in advance

Alex