Order of Upgrading?

[///M5 10+ year member]

Even parked with the engine off without proper installation which includes copious deadening and blocking off the leaky holes in the doors to create a more IB application your system will sound less than stellar. If you call that amazing, your definition is completely whacked. Stock speakers installed properly can outdo nice speakers in stock mounting regularly. I would assume from your post anmol that not only have you never deadened a car, but never been in one that has been done. Installation is the single most important part of a system by far and installation does NOT mean bolting new speakers in the stock locations. Proper speaking mounting requires a baffle, a vibration isolation layer for the baffle, door panel deadening (assuming door mount), sealing off the back wave of the speaker from the front wave, and aiming. Stock Civics sound loud as hell IMO.

 

[expo5.0 10+ year member]

honestly, neither of my cars really needed deadening all that bad

while my truck REALLY did

 

[///M5 10+ year member]

Any door you install speakers in needs deadening mat, acoustic foam, a heavy duty baffle, and isolation layer for the baffle and the big huge holes filled. It makes a huge difference.

I have driven a C class and the stereo is terrible and in dire need of deadening, my wives A6 is the same way, as is my M5 which is by far the tightest and quietest of the group. Either way they all needed a lot of help to get them to sound good including a lot of deadening.

 

[Rudy 10+ year member]

Any door you install speakers in needs deadening mat, acoustic foam, a heavy duty baffle, and isolation layer for the baffle and the big huge holes filled. It makes a huge difference.
I have driven a C class and the stereo is terrible and in dire need of deadening, my wives A6 is the same way, as is my M5 which is by far the tightest and quietest of the group. Either way they all needed a lot of help to get them to sound good including a lot of deadening.

I think it is safe to say that while the C class, A6 and M5 without deadening will be quieter and sound better than the Civic, all of them can be improved. The M5 is a great example of a car that is tuned to sound a particular way. The performance attributes are sonically enhanced. When it comes to optimizing musical sound quality, those beautiful engine and exhaust notes are noise. The stock Civic is always going to be painfully noisy, at least to my ears.

Even for great cars, like those listed, changes to the stock system will pretty quickly overwhelm the manufacturer's efforts to get the sound right. Sound deadening gives us the opportunity to ignore the compromises that every manufacturer makes and tune things to our personal priorities.

 

[focused313 10+ year member]

From what I've learned and experienced...

1. Big 3 Wiring Upgrade

2. Sound Deadening (front doors are a must)

3. Head Unit

4. New Door Speakers, preferably components

5. Amp for the components

6. Subwoofer (enclosure as well) + Sub amp