I'm running Sony Xplod 5.25"/6x9 off of my Aiwa CDC-317 (I think) head unit and I get rather good sound. I've tinkered with the idea of adding an amplifier, but I'm not really certain it's necessary. Given that most of the problems I'm having with my sound come from loose bodywork, an amp would only make that worse for the moment.
It is worth noting, however, that I do intend to install an amp eventually. I'd like to get a couple subs for low-end fill-in (like when I put Rammstein in) and you just can't drive a sub properly without an amplifier AND a crossover box (basically a low-end bandpass filter, really.) Of course, I've got to finish designing the mount that I want to use to keep everything out of the way, since my XJ is a hard-working truck.
Take some time to examine the sound you're getting before you commit to an amplifier. If you decide to add once, here are a couple hints...
1) Buy from Crutchfield. Their support is first-rate, and I've always been happy with their pricing. If you are going to DIY the install, BUY CRUTCHFIELD.
2) Planning - since you already have your speakers, plan accordinly when you buy your amplifier. You should never match your amplifier to your speaker's power handling rating - the amp should peak at 15-20% LESS than the peak figure on the speaker. You don't want to "hit the roof" with your amp/speaker setup, or you could end up going through speakers like popcorn.
3) Why are you planning on an amplifier? Chances are, you don't need to amplify the entire spectrum, you might just be looking for fill-in on a portion of it. Are you looking for more high end/low end/midrange/what? This is probably the most important question to ask yourself.
4) Wiring. Plan on using power feed wiring at least a size larger than specified (audio engineers seem to be a fairly conservative lot, and you won't hurt anything with a little overkill.) Also, think about where you want to run your wiring. On my Renix XJ's, the main FB harness runs through the driver's side doorsill, so I'd run amp signal wiring down the pax side. The power (DC) can go down either side, but turn signals/hazzards and other intermittent DC signals have caused "line clicks" on installations I've cleaned up for other people before...
5) Again, why are you thinking "amplifier?" I'm not trying to dissuade you, I just want to keep you from solving the wrong problem.
Feel free to PM or email me if you have any specific questions, and I'll give you what help I can. I've been playing with stuff like this for a while now, and some of it starts to stick...
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