I have all the components i just need to install. Whats the average size speaker i can use for a a4? and also how do you check if the speakers are blown or not?

 

Listen to them to see if your speaker is blown. The ones in the back have a tendency to crackle because of a bad glue job. Search the forum for more back speaker info. There is a write-up about how to fix them. Other than the back ones, just listen to each speaker individually and see if it cracks. I personally like the BOSE system, but I certainly wouldnt turn down a Boston Acoustic setup, nah-mean?

 

as far as I'm concerned, these speakers might as well have been blown from the factory - that's how terrible they are.

People say you can replace them with 5" - 5.25" speakers without too much trouble.

 

stock front are 4"
stock rear are 6.5"