FooFighter said:
If I was to do this would I need a 5-channel amp?
I assume that since my speakers are 180W max that an amp could boost them up quite a bit more than what my cheap Sony deck can. The deck says 50x4 but in reality it only give out like 15-20 per channel. Why is that? And would an amp make that much of a difference?
Sorry if this doesn't quite flow... I'm writing this between projects at work.
The amp depends on what quality speakers you have. For a normal "average" system, a 5 channel will work. Just make sure your sub is matched in power rating.
As for how things are rated: Most companies rate things in "peak power". This number is actually quite irrelevant, as your system will rarely, if ever, hit peak power. They simply use this number to make their products seem better. The average person only knows "more wattage is better". The higher end companies will rate things in RMS power because this is the number that should be matched between the speakers and amp. Even still, wattage is not the only factor. Sensitivity is very important because some speakers require less power for the same volume (labeled as the efficiency).
With the head unit, you want a higher voltage output when it comes to the amp, as it's a line level feed (wattage from the HU does not matter). A higher voltage is going to result in a cleaner signal, allowing higher volume with less distortion.
I don't recommend buying components on your own if you're new at audio. You have to choose the advise given carefully also. The sales guy will likely push the equipment with the highest commission or kick back for him, and most people into audio go strictly for "loud boom" without paying any attention to separation, clarity or balance (nor do most people actually know how to properly achieve this, specific to the type of vehicle).
An easy analogy for why you want power - you have to move a voice coil that's providing resistance. The key is not really more is better, as much as matching the required power of the speaker with the output of the amp. It's always better to slightly overpower speakers than to under power them. As an amp is pushed harder, the level of distortion goes up. So, if your speakers require 150 watts, but your amp only provides 100 watts, at 90%, the amp will cause a distorted signal, and eventually burn out the voice coil. Think of it like this: Which vehicle would run more efficiently? A geo metro with a hummer engine, or a hummer with a geo metro engine? In the first case, the engine would never be pushed past 50% power. In the second case, how far would that hummer make it before that little 3 cylinder engine **** itself?
With speakers, it's not quite that drastic, but it's the best analogy I could come up with, off the cuff.
The biggest thing I'd suggest is to figure out your budget and start asking for opinions.
Remember - if you're piecing it together over time, start with the subs. If you put high end speakers in first, you'll turn them up in an attempt to get more bass, eventually blowing them out before you get the sub. People always say they won't push the mains for bass, but they ALWAYS do. Buy your amps first, then your sub, then the main speakers. It requires patience, but it's so worth it.
