After what seems like a very long time, it's my turn to start upgrading
What I have at the moment:
2007 E91, Professional HU with iDrive
Ground Zero shallow mount 4" components
Ground Zero 8" Shallow Mount subs
With install adaptors
Everyone knows there's a limited choice of speakers that will fit, as both the speakers and the subs have to be shallow mount. These are, and the specs look good, so I'm happy to try them, especially given that the components are half the price of the Focals and Rainbows.
On the basis of cost AND simplicity, I decided NOT to recode the stereo, and to instead go for a JL Cleansweep. Found one on eBay from a car audio place in the US. Even with UPS shipping charges it's half the price of anywhere here in the UK.
Because the Cleansweep outputs a 'normal' signal, I had my choice of amp. The biggest limiting factor is the space under the boot floor, specifically the depth. Add the power requirements of the speakers into that mix and the choice narrows down even more. I've had very good experiences with SPL Dynamics kit in a previous install, so I'm happy giving this amp
Add in a bunch of wires and that makes a very exciting parcel headed my way this week! Not sure when I'll get the chance to install it, but I've read pretty much all the other DIYs on here, I'm happy with what I'm doing, so it should be fairly
I'll keep the thread updated with progress as and when I make it