Hi guys, wondering if you could help me, I want to get a 200w amp and a subwoofer in my car along with replacing the 4 speakers and tweeters, but by doing this will i have to replace the headunit, but if i do replace the stream headunit with a better one will it leave a massive gap in the console, and what would ye suggest as regards a suitable headunit replacement and decent speaker set up? Sub will be going in the boot along with the amp. Thanks

potentially lots of different combinations, but the basics are:

Head unit - you can either buy a single DIN head unit + a facia adaptor that will fill the gap and more than likely give you an little storage compartment, or you can buy a double DIN head unit which will fill the full space with no gaps.

Speakers - Components split the high and mid/low range tones between 2 different diaphrams (you have 2-way co-axe which will go in the doors and then a tweeter usually higher up on the door or on the dash) - or you can have 3-way co-axe speakers that have the tweeter mounted in the middle of the speaker cone.

Amp - you will want at least a 5 channel amp to allow all the speakers to be wired through as I personally dont see the point in going to all the effort to wire an amp for a single woofer. This isnt the place to be frugal either, you get what you pay for as this is what is going to be pumping the power to the speakers.

Woofer - the smaller the diameted, generally the tighter the bass, bigger normally will be a little bit louder but tend to not be as tight, more prone to a bit of farting at higher volumes.

Im my last motor I had the following installed which sounded sweet as...

Head unit: Kenwood single DIN (cant remeber model)(£350)

Front Speakers: DLS components (£150)

Rear speakers: Alpine 3-way co-axe (£45)

Amp: 5 channel DLS (£375)

Sub: think it was a Diamond Audio 12", would be lying if i gauranteed it (£120)

It was installed in a Clio which i had laced with sound proofing. The components had additional high ans low pass filters which made a bit of a difference too, and as i said, it sounded very crisp and had an awesome balance of bass, mid and treble.