Car Stereos: 99 GMC Sierra amp and sub question, rca cables, gmc sierra

Question
I have a 1999 GMC Sierra SLT extended cab everything is stock on it and
I was looking to install a sub or 2 under my back seat and of course an
amp but im new to this and I dont know how to install all that on my
stock radio. Can you help me out? A list of stuff I would need to get
would be great too.  Im also thinking about changing out my other stock
speakers too. Any suggestions on that?

Thanks,
Dylan

Answer
Hi Dylan,

You can find vehicle-specific subwoofer boxes for your truck, available in single or double versions.  Atrend is one manufacturer for this type of box; you can see their lineup at http://www.atrendusa.com .

In addition to the box and subwoofer(s), you'll also need an amplifier and wiring kit.  Your factory radio doesn't have RCA outputs for connecting an amplifier, so you'll need to make connections to the factory speaker wiring.  Many amplifiers have high-level or speaker-level inputs for this purpose; otherwise, you can get a device called a line output converter, which allows you to connect RCA cables to the stock radio's speaker outputs.

Here's what you'd need to install a subwoofer into your truck:

--subwoofer enclosure (box)
--subwoofer(s)
--amplifier
--amp wiring kit, including power and ground wire, fuse and fuse holder, RCA cables, remote wire, and speaker wire
--battery terminal post, for connecting power wire to a GM-style side-terminal battery
--line output converter (if the amplifier isn't equipped with high-level inputs)

Your truck uses 6-1/2" speakers in the front doors, and 4x6" speakers under the rear side panels.  Upgrading the front speakers can make a pretty significant difference in your sound quality; the rear speakers are less important to the overall sound (and fairly difficult to replace) so I'd leave them alone unless they're producing distortion.

Hope this helps!

Brian