I have two brands of speakers in my 2 cars, and have been very pleased with both: Diamond Audio, and MB Quart. If you decide to add a subwoofer, I think that JL Audio's products feature good power and musicality.
Here are the web site addresses:
1. Diamond Audio: http://www.diamondaudio.com/
2. MQ Quart: http://www.mbquart.com/2003/en_US/home/
3. JL Audio: http://www.jlaudio.com/
Here are the web site addresses:
1. Diamond Audio: http://www.diamondaudio.com/
2. MQ Quart: http://www.mbquart.com/2003/en_US/home/
3. JL Audio: http://www.jlaudio.com/