hi, alot of this depends on what head unit you have? how many RCA outputs does it have?
for now I'll assume it has one (like my JVC headunit)/
I have in the car at the moment, a cheap jvc running some 6x9's which i would like to keep the head unit in there as i dont want to spend loads and the car needs other things so dont want to blow money on a new headunit, but have been told that i will need a all singing all danceing one, would like not to if i can.
you can leave the 6x9's running on your head unit this wont cause any problems, although youll get much better sound if you amp them correctly.
Want cables do i need do i need to fit all this (any links)?
It sounds like your fairly new to this sort of thing so your best bet is to buy an amp wiring kit the kits come with everything you need to wire up an amp, you need to make sure your get a kit that has correctly rated wires for your amp.
this one is only rated upto 300 watts
Link this one will handle upto 480 watts and comes with speaker cable for wiring up a sub
linkthey're just two examples of what your looking for but anything similar will do aslond as its rated high enough for your amp.
How hard is it to connect the amp up and how do i no that its working etc?
Easy, alsong as you have a basic set off tools; wire stripers, wire cutters, soldering iron (not necessary but i would recommend). your amp probably has two lights on it one saying 'protection' and another saying 'power' if you've wired it correctly theese should come on, and well you'll hear your speaker/sub.
here's a guide to amp wiring with a basic wiring diagram on
linkWill it work ok with a cheap jvc head unit, i no it might effect the qulity however im not to bothered.?
simple answer yes, but if you only have 1 set of RCA outputs then your limited to running one amp, unless you have an amp with high level inputs/speaker level inputs. I dont know alot about wiring multiple amps with only one amp output on the headunit, to be honest, so thats the best i can do maybe someone else can advise.
Plus i dont want my battery to go flat all the time.
if you only put one amp in you should be fine (depending how big it is). im currently running a 300watt amp and have had no problems with my battery going flat but if you do you can always buy a bigger battery and a bigger alternator.
More info about bigger batteryBigger alternatorHope this helps if you've got anymore questions i'll try to help.