Alright so I have Infinity Kappa series 6" x 8"s in both the front doors and in the rear deck. Now its time for me to hook up my 4 channel amp to push those babies. I have a Boss Audio Chaos 350 amp and it is not very big. Its about 10" by 8" is my rough estimate. I'm wondering where would be a good place to mount it that would not sacrifice cabin space and will allow it to be out of the way. I have a 2000 Mustang Coupe and I had thought about going under one of the front or rear seats. Anyone have any experience with this or know of a good location? I don't really want it in the trunk because then it is far away from the front speakers but if it comes down to it I'll mount it under the rear deck.
Any and all advice is appreciated

I always stick them in the trunk and it just depends on what I am trying to achieve. I have made shelves that hang from the rear deck, mounted directly to the rear deck upside down, installed on the floor of the trunk, installed on the subwoofer enclosure, and installed on the back of the rear seats.

I take it there is no place to install the amp under one of your front seats?

i ended up mounting it on the back of one of the rear seats. only problem is i'm getting a buzzing sound when the volume is at 0. i'm dissappointed in this amp because it doesn't really sound much better than just my alpine cda-9884 pushing it. 3 hours of work gone to waste i guess.

Did it make the buzzing sound before?

If not, I would check the ground wire and make sure it is connected to a nice, bare piece of sheet metal. Sand if you must!

Another issue could be if your rear seat backs contain metal and you have no isolation. In other words the metal from your mounting screws are screwed directly into other metal causing another grounding point. With modern amps, this is usually not a problem, but it can be in some instances.

Check to ensure that all your RCAs are connected properly and not routed directly next to the 12 volt power from the battery. Sometimes when running the RCA on the same side of the car as the 12 volt positive wire, you will introduce noise.

Another test you could perform is unplug your RCAs from the amp while it is powered off then turn the amps on to see if the noise goes away with the RCAs disconnected. If it goes away, you could have a ground loop issue and I wish you lots of luck with getting it solved. The first and foremost thing I would do is change the grounding location of the head unit by grounding it directly to the vehicle versus using the factory ground wire that connects to the harness.

If it doesn't go away with the RCAs disconnected, then I would think there is a problem with the amp OR the gains are set too high.

Keep in mind, these are just some recommendations and I may have missed a few because I am tired. Regardless, noise that is not supposed to be there really annoys the heck out of me and I will spend more time tracking it down, re-grounding, and re-routing wires than the actual install itself took!

Lastly, I leave you with a little story. I once traced a noise problem to a bad set of RCAs, so now that is the first thing I swap out when I have noise problems. You don't know how stupid I felt to literally gut the interior of the car and re-route every wire only to find that one of the RCA cables had a minor short in it.

One more thing. I just looked up the specs on your amp and it appears that its rated RMS power is only 40 watts per channel, whereas the Alpine is about 18 watts per channel, hence the reason you don't notice much of a difference.

When I connected my Kappa 6x8s to the front and rear channels of my Power 1000, I noticed a HUGE difference! I am putting a little over 100 watts RMS @ 2 ohms to each 6x8 and I crossed them over at 80 Hz so that they don't get any low bass.