5.1 Speaker Cable Extenders

So I have a set of Logitech 5.1 speakers and only 2 of them have decent length. In order for me to rout them to each corner of the room I have now, I will need about 15 feet extra for each speaker(except for center one). All of them plug centrally into the bass so I am not sure if that is a Logitech proprietary socket or not. Do these cause a significant loss in audio quality or do they tend to work pretty well? Any ones in particular that I should look at?

I don't see the exact ones that I bought but these are pretty close: http://www.newegg.com/Product/Product.aspx?Item=N82E16836121044

Google is falling somewhere between saying they are indeed proprietary to saying there is a 9pin serial cable?? That's weird as in my experience, Logitech speakers are either 1/8th in or RCA

http://www.amazon.com/Logitech-X-530-5-1-Speaker-System/dp/B0002WPSCG Found them.

http://forums.logitech.com/t5/Speakers/I-Need-To-Extend-The-Cable-Length-Of-My-X-530-Speakers/td-p/741002

Of course, the tech support dimwits act like fucking dumbasses. I like Logitech products but responses they provided pissed me the fuck off. Repeating yourself serves no fucking purpose. I just checked and the main speaker that has the volume adjuster has a 16 pin connector that goes to the sub. It is a short fucking cable meaning that if I extend the other three, only 3 of 4 corners will be covered resulting in sound imbalance. Fuck.