Thanks for reply....
want to know few more things. What should be the power of the mentioned units. Like front speakes, rear ones, amp, sub etc. Does power plays role in sound quality? What is damping, coaxials, 2 ways you wrote about?
I might not answer it very accurately but I will make an attempt. Just like home audio components, car audio components such as AMPs, speakers etc have their power ratings, ohms etc. It is not that you will have problem if you mix and match. But it would be best if they complement each other. For instance a AMP spec would say something like 100 watts at 8 ohms and say for example 120 watts at 6 ohms (all numbers are just for example and are not accurate). So see what your speaker spec says in terms of power handling / ohms etc and see if your AMP will be a right fit (or otherway). There will always be a threshold so a little less or little more is always fine. Like I said earlier even if they dont completely match, it would still be fine as long as you dont take it to their extremes/limits and test them (like crancking up too much volume etc).
If you are planning to buy a 4 channel AMP and bridge 2 channels for the sub I would advice you to certainly look at the power ratings as the bridged connections should give enough juice to the sub, otherwise your sub will not sound effective.
If you shortlist a few combinations, we can help you if they will all compliment each other or not.
Just like home audio, where they say for example Norge 2000 is laid back and Norge 1000 is neutral, the AMPs in car audio also have their own sound signature. You will have to do some research and find which sound signature you like and which AMP will suit it.
Damping - If you want to create a dedicated room for HT, people go for carpets on the floor and curtains and even make some modifications to the walls etc. This is just not for decor but also to absorb the bouncing sound waves(?) - to avoid reflections/reverberations that spoil the SQ. Same way in your car, you can pad your doors, even floors, ceiling with a material to absorb the bouncing frequencies. It also helps with the rattling sound which are prominent in our cars (due to the road, car build quality etc). Damping does make a difference in SQ but must not be one of the very first item in your to do list. You can damp your car at a later point when you want to improve your car SQ with existing equipment.
The 2 things that hydra spoke about are
1) avoiding rears if possible to allocate the budget for a better HU, fronts, AMPs
2) To build your car audio step by step instead of going for everything in
one go - i.e. to buy a good HU, fronts first, then add a AMP, then add a sub.
IMO HU and fronts are very important. If you dont have a proper HU, then no matter what you add later, certain things may never be possible to achieve.
A bass-tube is all about boomy bass with no definition.
