Right without a budget you could spend anything upto £15,000!
Spec wise I'd go for hu, comps up front, 2 ch amp for the comps, 12" sub, mono amp for sub, sound deadening, updated battery, knu konceptz cablng throughout.
If you keep sub power below 1.5kwrms you shouldn't need to worry about alternator upgrades or multiple batteries.
1.5kwrms will be more than enough if set up correctly.
Good hu's.
Jvc avx77 top end, flash, dvd single din. £500
Alpine ida x300. £300
pioneer p77mp. £100 second hand
components you can spend anything up to £10,000. I'd say some brands to look at are rainbow, focal, cdt, hat. You'll be able to find a set in whatever price range you decide. Ideally you wanna listen to as many pairs as possible as they all sound different.
2 ch amps. Dls, genesis, diamond, rainbow are top makes again have a look there's loads of options. I'd say aim for between 70-120wrms that should be plenty enough to keep up with the sub.
Sub makes. Fi, re, aa, dd, spl dynamics. A 12" from one of those will make you smile. Look for an rms rating of around 1500wrms.
Mono amp. Massive audio, us amps, Orion, spl dynamics. These are big boy amps up to 7kw & above in some cases.
In the boot of my mk3 I've got a 3cu ft box tned to 30Hz for a single 12". It's a monster of a box but will make your sub Wang. You'll need a good box!
Sound deaden the boot & the inner & outer door skins as a minimium. Ideally you want to do the roof as well. This will help improve the sound in the car.
You'll want 0awg power cable, an uprated battery (nsb 90 would be nice or similiar).
You could probably do the above for around £3k.
