Audio Systems: 96 Toyota Avalon XLS - Speaker Problem, toyota avalon xls, toyota avalon

Question
I have a 96 Avalon XLS with 6speaker system (4 5" in the doors and 2 1" tweeters front).  I just replaced the stock HU and speakers with the following:

Blaupunkt Bermuda HU
Eclipse 2-way 8253 5.25" Speakers (4)

After getting everything setup, the sound isn't that impressive.  The highs are super bright and the bass sounds muddy.  Someone told me there's a factory amp I should have bypassed but didn't, and that's what's causing the problem.  Do you know anything about this?

Thanks!
Ben

Answer
Hi Benjamin!
Yes it could be one reason, but you don't necessary need to bypass the factory amp, the problem is the phasing of the inputs, is quite complicated to get the correct phasing for the 4 channels, but an easy option is to use a factory amp adaptor like this one:
http://www.scosche.com/scosche_caraudio.aspx?CategoryID=36&ItemID=OEA4