If anyone would know of how to build an amp for my car, or know of Amp kits, please let meknow because I have electrical experience and would love to build my own amp then buy one. I appreciate the help if anyone does help me. :-D
Amp easy. Power supply hard. Need more than 13.8V to get decent power (like for subs), so it needs to be a switching supply. Building switching supplies is more complex than building amplifiers (well, most amplifiers), so you won't see much on the DIY front. After I watched a pretty smart electronics guy spend two months trying to keep his switching supply output transistors from blowing up, I decided this would be too much of a challenge.
But search through the threads here, maybe using "car amp" and you'll find some stuff.
As Paul said, there are threads about the matter in this forum. They indicate some articles and tips to build power supplies (more complicated job, for sure - but it's possible to do), complete power amps and other usefull information.
Well i do not found switchmode PSU to be very complicated. I didn't try to go that high in power tought.But the thing with that if you use transistor to do the "switching" it'S like building to amp.(2x the transistor 2x+ heatsink). A good way would be using MOSFET for the PSU. There also a woy with some special tranformer but I never see those circuit.
I would recommend you buy an amp like a Pyramid PB590 or PB300 and modify it.The PB300 has the same supply as their PB600 just fewer switching transistors(4 X 26A vs 6 X 26A).Remove the IRFZ34 26A parts and replace with IRFZ44N 55A parts.They use 8A outputs.Replace with TIP35C/36C 25A parts.The result will keep up with a $500 Rockford amp for the cost of a $59 Pyramid plus $15 worth of parts and some of your time.And no self-respecting car stereo theif will steal your 'Pyramid' POS amp.
Im not sure how much power your pushing or how much money you are willing to spend, but there is a special car audio power supply you can buy for like 30bucks but it only lasts like 20hours (hehe)
Other options is you can upgrade your alternator and get caps; preferably 1farad for each 1000watts.
As for building an amp I know nothing about that.......