Can you fit a sub to a ford factory radio?

I want to put a sub into my 03 ford fiesta but don't want to pay for a new radio, does anyone know if you can fit it to the factory fitted radio? I've had a look but it appears to me that it dosent come off.Can you fit a sub to a ford factory radio?Umm. Listen its very easy to do and yes the quality is there. Many companies make a factory add on woofer that's actually have an amplifier built in. Including MTX, Infinity, Bazooka, and many many more... These type subwoofers often include all wires and brackets needed to install. Often they blend in or hide away to keep the factory look. Crutchfield.com carries a large selection. Call them up and tell them your needs to get a better ideal of your options. Even if you do not intend to buy from them. They are very helpful and carry thousands of brands. I have recommended do it yourselfers to them plenty of times because they are not bias compared to brand specific dealers.Can you fit a sub to a ford factory radio?Yes and it is rather easy but the negative side is since the factory head unit wasn't set up to run subs so the sound quality you get isn't optimal. Such as you have to have the bass turned down so you don't blow your stock speakers and with it down it effects how loud you can get your sub in regards to the highs and mids.Can you fit a sub to a ford factory radio?All you need to do is wire a cross over network to the factory speakers to separate out the sub base frequencies and use the leads from the cross over to power the sub-base. No need to pull the radio.