Hi I have a Kenwood Z838W mp3 head unit ( gapless mp3 playback ) in my Toyota Camry. At the moment i have the factory speakers running from it. fronts are 6 1/2 with (factory original) tweeters mounted at the door mirror positions. In the rear parcel shelf are the original 6 x 9 's. I want to improve the midrange clarity and get a bit more 'life' into the sound. If at all possible i want to avoid adding amps. the 50w x 4 from the kenwood must be enough? I'm not into earthquakes on wheels! The dealer where I got the Kenwood said that 'components' must have an amp to drive them and offered me some cheap (£40)Kenwood 2 way 6 1/2's for the doors. Is that really the best I can do without an amp? The factory speakers aren't *that* bad... but i can tell the sound could be cleaner. Any thoughts?