I really like the Mark Levinson systems for cars
It is one of the most challenging things I’ve done.You know, it is actually way harder to calibrate the quality of the sound in a car. It is really ... complicated because there are many more factors that actually affect the sound in a car. First of all, it is a moving object, and the sound insulation is also really important when calibrating a sound system in a car. So yeah, it is way way tougher, in case you actually want to make it work perfectly. You could actually find some really useful information about it on cararac, as they are having a lot of great articles, and all of them are related to cars.