Where are you based? Often it is easier to come out armed with a multimeter and good ear to diagnose things like this, rather than write back and forth for three pages.
You want to meet up somewhere so I can look over the system for you and diagnose the problem?
We don't charge anything for just diagnosing either before you ask.
Even though I am in NSW, I do recommend certain installers in Melbourne quite often.
My recommendation is:
John Angelopoulos
JohnA@auscaraudio.com
0404 024 847
Central Car Radio
883 Nepean Highway
Bentleigh, VIC, 3204
(03) 9563 9500
Okay, now I'm getting concerned. If it's getting to the stage where head lights are not working, it's time to call a professional installer or Auto-electricain in.
It could be something to do with your dimmer wire?
If you're handy with fibreglass you can easily mount a small sub next to the battery. We do it all the time with Skylines and Soarers.
As for effecting sound, your subwoofer should be crossed over quite low (around 100hz). At this frequency the sound will not be noticealbiy effected at all. Remember the front speakers are the ones that have the important task of creating and reproducing the 'body' of the music. The subs simply fill out the lower end of thre sound spectrum.
We quite often build systems in stages.
It's the smart way to do things and like the guys said above, saves you the trouble of ending up with useless components.
High quality QLD based mobile installer hey?
I strongly recommend you get in contact with a bloke named Chris Rogers. He has been installing for years.
Email him at chris@soundoff.net
When talking high quality systems that includes a sub and amp, a $1000 budget is a little small even given the fact that you have the deck.
But if that is the absolute maximum I'd suggest this (which is one we have done many times too just quietly)
Boston FS-60 6" splits at the front (doors and kicks)
Audison SRx4 amplifier
Jl 12W0 subwoofer
Stinger cable.
You would probably end up spending $1200-$1400 when you factor things like installation and sound deadening in but I tell ya what, the end result would be well worth it.
Depending on just how much work you want to undertake you could knock up some spacer plates and see if you can fit the additional 10mm under the facotry trim?
Might not work but I cannot hurt to have a go.
Kind of tough that hey.
Try getting the depth measurements from the Focal website?
Now I think about it, I think the Utopia's are a couple of MM deeper too.
Just remember anytime you're wiring amps and other audio related items to upgrade the negative battery lead.
Electricity travels in a circuit. If you don't upgrade the earth cable then most of your current will not be able to return, thus rendering it useless.
You shouldn't have any problems fitting them in.
Just remember though if you're going to splash on high-end speakers like Utopia's, at least do them the justice of sound deadening your doors and installaing diffuser panels to minimise wave reflection and cancelation.