True, but you can add a nice sound system with it adding weight. Replace the the speakers with some nice Infinity Kappa's, with baffels and a high quality head unit with a good amp. That would give you "sufficient" volume, great sound, and a kick.
This is coming from someone who competed in SPL competitions with his focus and had 3 12" subs pushing over 3000 watts through them.
You can make the car sound good with out adding more weight with amps or subs.
2001 ZX3 2.0L Zetec-
Hatch Nation #42
Going through Rebuild See "The TICK Build Thread" for details (http://www.focusfanatics.com/forum/showthread.php?t=289168&referrerid=62897)