I have a 2002 9-3 that came with the 40 Watt amp upgrade and two Low to Mid range speakers. The speakers are pretty bad and I wanted to upgrade them to full range speakers ( A pair of 3 way alpine ). The problem is that when I replaced the first Saab Low end speaker with the Alpine, The Alpine did not produce any Mid to High range. It's the same output as the Saab Low to Mid range speaker. I then assumed that a crossover was on the amp but I can't find one. How do I could full range sound out of the Amp?