I am fairly new to the forum and haven't posted much. Hoping you guys can shed some light on my situation. My basic question is this. Do I really need to install an amp to power my door speakers if my system already sounds pretty good? Here are the details.

I have an '05 Screw. It has (had) the basic 6-cd changer with no factory subwoofer. I am giving the truck to my son so I decided to upgrade the stereo for him. Here is what I bought to install.

Kenwood DPX500BT
4 Infinity Kappa 682.9cf
ROCKFORD FOSGATE PUNCH P400-4 400 WATT AMP
MTX Thunderform Subwoofer Enclosure
Amp kit, distribution box, radio harness and install kit, speaker adapters, etc

The first thing I did was remove the factory deck and speakers. I then installed the Infinity speakers in the doors. I temporarily connected the deck just to make sure all of the speakers were working (I had already soldered the harness so connecting the deck was easy). To my surprise, the thing sounded pretty dang good. I considered not even putting in the amp.

But, I figured since I had it, I might as well go ahead and do it. I removed the back seat and the mat against the back of the truck to figure out where/how to mount the amp. There wasn't a ton of room since the truck also has the power sliding back glass and the motor is mounted back there. No matter where I thought to install the amp, it looked like it would be a pain in the butt.

So, I decided to go ahead and connect up the thunderform and see how the system sounded with the subwoofer installed. Again, I was blown away. I couldn't believe how good it sounded with no amp installed.

So, is it really worth the expense and effort to install the amp? Will it really sound that much better? I just wanted to get you guys opinion on it. I have plenty of time to do the install and I don't mind doing it. Of course, I can return most all of the equipment I bought related to the amp and just go fishing instead. What do you guys think?

 

At least install an amp on the sub, otherwise might as well remove it and move the bass setting up one notch on the headunit.

I'm assuming that mtx enclosure came with some sort of mtx sub in it right?

As for the door speakers, if your happy with the way it sounds, I wouldn't worry about amping them.

 

I think the MTX enclosure has both subs and an amp all in one package? Otherwise the subs wouldn't really do anything at all.

I don't have an amp on my door speakers, but I want one for those times when it's just not quite loud enough. Whether it "needs" it or not is mostly determined by the RMS needed for the speakers to sound "right." But if it sounds good already, an amp is just going to make them louder, not necessarily noticeably better.

Another reason I don't have an amp on the speakers is cost and PITA factor, so I wouldn't bother with it honestly.

Wish my dad gave put a stereo in my truck, would've saved me a $1000

 

The sub enclosure is the "loaded" version. It comes with a 12" sub and a 200w amp. The bass sounds really good for the type of music we listen to (rock and some top 40). I'm sure the rap crowd would want more, but it hits plenty hard for us.

I guess I will leave the door speakers as is for now. We can always add an amp later.

 

Yea, what you said about the RMS needed for the speakers is what has me thinking they would sound better with an amp. The speakers are rated at 100W RMS and the deck puts out 22W RMS. The speakers are 2 ohm and the RF amp I bought puts out 100W RMS at 2 ohm. I can't imagine how they could sound much better, but everything I have read says that the closer you have the RMS to the speaker rating, the better they will sound. I guess it's hard to say how good they could possibly sound until I actually hooked up the amp and tried it.

I'm 70-30 for not installing the amp right now. You are right about the PITA factor. That is more of a factor for me than the cost (although it is still a factor).

And as far as buying it for my son, he doesn't really do a lot of extra-curricular activities. My mom and dad spent a fortune on me playing sports and running me up and down the highway to baseball practice and games. Plus I went to a lot of baseball camps (I was going pro you know ). He takes a lot of AP classes in school in preparation for college. So, I figure I can do this for him. The funny thing is, he keeps telling me I'm spending too much!

 

Speakers are 2 ohm?

In that case the amp may need to be installed so you aren't replacing the headunit when it's internal amp blows. Headunits are rated at 4ohms, not 2. So your overdriving the headunit now, and any extended period of play could blow it, light it on fire, etc.

 

I thought about that but then I saw this on the speaker specification page. Do you think it might only be marketing BS?

"True Four Ohms— All Kappa speakers feature two ohm voice coils. Original factory-installed speaker wiring in many cars is 18-22 gauge. This wire, and heating in the voice coil when power is applied, increase the impedance “seen” by the amplifier or head unit. The impedance of Kappa Speakers has been adjusted to compensate for this increase and can be safely driven by any head unit."

 

Hmm if they're rated for 100, you may just want to amp them and have them sound ridiculously good. You must've spent a lot of money on speakers like that to not be using them to their full potential. But, the Alpine type S (?) speakers in my old truck were rated at 65w and I had a single din Kenwood giving them 22w (no external amp) and they got louder than I could handle while still staying crystal clear. I got a great, super low price on Boston Acoustic speakers this go round, but they only handle 35w and my touchscreen Kenwood with the same Mosfet internal amp isn't able to get them anywhere as loud. Not sure what any of that is worth, but if they can handle 100, might as well give em 70 or so. I was concerned with those 65w RMS speakers needing an amp for the same reason you think yours may need it, but I never had an issue with them.

I'm one of 4 children and in college right now. The brother right below me doesn't really do a lot of extra-curriculars either, where the other 3 of us have played sports non-stop since we were 3, so I understand that and I know what my parents do to substitute for it. He doesn't give two-sh*ts about school either, but there's more to that haha. My truck was a sort of reward for taking APs, staying out of trouble, and getting into A&M, so I gotcha on that too. I ended up buying my truck from my parents at 70% or so of the cost though when I graduated. I, of course, had to blow WAY too money on modifications too . . . Your son sounds like he really has his head in the right place if he recognizes and appreciates how much you're spending and what you're doing for him. Too many ungrateful youngsters out there today, and I've certainly been guilty at times.