I have a 2004 fx4 with a 10in sub I just but another 12in. I'm new to all this stuff so forgive me if I have some "dumb" questions. My question is can I run these two subs together? What size amp should I use? And is there anything I have to change so that it all works properly

 

On the bottom of the subs there should be a sticker that tells you how much power they can handle. And what ome load the symbol for the ome load looks like a little pair of headphones.... They are mostly 2 or 4 ome... They have to be the same to run them together.

 

well, some may say you shouldn't. and some may say you can't. but you can. the important issue is ohms. you have to match the ohms of the subs to the amplifiers output. if you have 2, 2ohm subs and you run them inline(+ to + and - to-) that will reduce the ohms(resistence) to 1ohm. if your subs are both 4ohm subs then inline they will be 2ohms. check crutchfield or sonicelectronix.com. i would also recommend separate enclosures or at least chambered. it could sound really good. you'd get the deep, rich bass from the 12" and the punch from the 10".

 

i believe they do not have to be the same. as long as you do the math and match the combined ohms to the amplifiers output.
op, time to spend some time on google.

 

also depends on the amplifier. If your running on 2 channels, 4 channels or mono.

 

Personally I would make sure that they are separate boxes. That 12" could do some really bad things to the 10" just because of the volume of air it moves. Secondly I wouldn't run the subs on the same channel if they are going to be run on the same amplifier. Just my $.02

 

It'll work fine as everyone said. Just don't put them in the same chambered box. The air pressure the 12 moves will overpower what the 10 is doing creating pressure against the woofer and distorting its movement and sound.

Learn about ohm loads and how to wire them (easy). Keep the RMS power near which ever sub is weaker and it'll be fine.

Some may have a sensitive ear to different sound that's hitting. But would really have to sensitive to it and those are the ones that say you can't or shouldn't do it. I suspect not many will notice.

 

I forgot to mention that my 10 in is a factory sub under the seat. The 12 is a hifonics Zeus. What kind and size amp would you guys recommend?

 

hmm well now you have yourself a different ballgame...so you have a completely stock stereo otherwise but now have a 12" sub lying around?
Look at the RMS and PEAK rating for the sub and let us know what it says and then we can recommend a good amp for ya...

 

if you have a stock headunit you will more than likely want to upgrade to an aftermarket. at that point i would bypass the stock amp and sub completely. be sure your new amp can handle the needed RMS (constant power) the sub requires otherwise overtime you will distort the speaker.