Since it's still going i'm going to throw my 2 cents worth in. To all the people saying Fusion is crap, your just brand bashers and clearly do not have any useful knowledge or experience to offer. Ok so Fusion might not make the best sounding speakers in the world, but then again they do not sell the most expensive speakers either. They mainly target the lower end, so there is no point in comparing them to anything but that.
For someone who needs a pair speakers, whether they be an upgrade, or a replacement for an existing component, there is nothing wrong with them. You can spend a lot of money with a bad instal and no knowledge and it can wind up sounding fairly average.
On the other hand you can use some budget components, such as what fusion offer, and with some knowledge about what your doing, and a good instal, not just dropping things in and wiring them up , and have a fairly decent sounding setup. This can be confirmed by a fellow member here who actually won a SQ comp using a pair of Fusion's Reactor line speakers.
I'm not supporting the brand, but all you people arking up saying they are rubbish really need to stop and have a think. The OP's problem most likely arised from using a speaker with a lower sensitivity than the factory ones, which resulted in less output from the head unit, it could have even been a simple polarity mix up, we'll probably never know.
But telling him (or anyone else ) that they purchased the wrong brand is not helpful advice.