In my opinion, a good headunit will negate the need for a 5ch unless you really want to go big, bad and top of the line. You never want to use a multi-channel amp as a subwoofer power supply(too many nightmares, less lifespan, etc). Yes it is rated to handle it, but, if you had a car that would blow up at 110mph, would you constantly drive it at 105mph? Same kind of principle. Get independent ALWAYS for a sub. Only exception I can think of is if it's just a super small 200w max kind of sub. Every single professional audio equipment tech should be telling you that upfront =\ That's all I've ever heard from all the pros around all the shops I've ever been to.
If you truly need that extra ~15-20% clarity and power bump, then go ahead and get a decent quality, preferably name brand, 4 ch with the independent for the sub.
What all are you planning on running? like what kinds of wattages on the 4ch system? There's a lot of smaller form factor amps that can easily handle 40-60rms per channel, 100 max that would fit with a little bit of creativity.
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Originally Posted by JasonStebbins
We can call it the Whoosh King Catalog System. :D