Bass goes through walls even though it sounds crap on the outside its awesome on the inside, only reason they sound like rubbish on the street is because the cars rattle and distort the sound coming out, not like they use to sound in old cars which where made of steel and not foil paper and plastic.
If you want crisp loud sound without distorting then its best to run a amp off the speakers not using the head unit in built amp to drive the system, most units have front and rear AUX output cables these days, I had 4 ways 7x10 Kenwood's in the back running off a amp to get that extra drive for punch and 6.5" splits up front to fade the back out when carrying passengers in the back, then I added a 12" sub and ran the 7x10 as high end cutting out the bass, these days as I'm not young no more I have two 8" open air soundstream subs in parcel shelf for punch and 6.5" pioneer splits up front with 6" 3 ways in the back doors also Pioneer, sounds pretty good for me without going overboard. I have a Chinese double din with GPS made by Eonon works a treat.