well i called over to a couple of shops and i got set up with a JL 8w3 v3 and a JL HD600/4 amp and they said they are willing to build me a custom box so it came out to be 950... plus some work on my dads miata he needed an alarm
you guys think this is a rip still? is cheaper than the first proposition and I am getting a better amp... (my justification??)
You sure you listed the right model number for that amp? First, that amp on crutchfield is listed as $900, and second, it's listed as a 4 channel amp, which would be to power your front & rear speakers, not the sub. Just from a quick browse, the XD600/1 looks like a better fit for the sub, though I have no experience with JL amps, so I don't know whether that's one of their higher or lower quality lines. Anyways, cost breakdown for parts based off online pricing:
$190 for sub - JL Audio 8W3v3-4
(250W RMS @ 4 ohms)
$400 for amp - JL Audio XD600/1
(400W RMS @ 4 ohms through 1 channel)
$50 4 gauge wiring kit. (this is just an average guess from a quick google search)
$70 Amp install labor charge (based off bestbuy.com)
This means you're probably paying around $240 for the sub box build & alarm install. That's doesn't sound horrible to me considering you're having a custom box fabricated. I'd like to hear from those who have had this done before though. I've always just used a mass produced box.
Just another quick thought. I used to have the Alpine V-Power 500W mono amp
In my Trans Am, & I think it would probably work great with that JL sub (300W RMS @ 4 ohms), and it's only $200. Just to give you something else to think about.
Not sure if this helped or not, but at least you can see some quick prices for components for comparison. Let us know what you end up doing.