I am wondering how reliable this new setup of mine will be. I had some old kenwood 12s rated at 400rms each at 4ohms each powered by a kenwood 1000 watt amp. I have ordered a new setup and all but the subs are in. I have a pioneer AVH-4300dvd that I will be replacing as well and will be up for sale soon.

Here is what the new setup consists of:
Alpine MRX-M240 amp (2400 watt at 2 ohms x 1. Monoblock)
2 Alpine type R SWR-12D2
Streetwires ZN5 amp kit
Pioneer AVH-4400BH

My question is, will this setup run reliably? Crutchfield told me that it's better to run a little over the max rms than under. Is this true or just a ploy? I have no audio experience and need some advice. Thanks.

 

No Sagara, it's not a ploy. It's always better to have too much power than too little. It all has to do with clipping.

Imagine a sine wave (the smooth up and down wave) that's making your music (in your case, bass). It's got smooth peaks and valleys. Even when it's a hard bass it, it should be clean and smooth looking. An amp that does this has good control over the sound, ie, it sounds good.

Now chop off the tops and bottoms of those waves. That happens when your amp doesn't have the power to play those peaks. The sound gets chopped off, raspy sounding.

The danger is to the speaker is not raspy sound, but overheating. In a clean wave, the power goes up then comes back down immediately. Imagine turning a light bulb on and off. The cycle would be on-off-on-off, etc. The bulb will get warm, but not blazing hot. Clipping extends the heating cycle: on-on-off-on-on-off. Now the bulb has a chance to get hot. In our case, the voice coil starts to get hot, eventually melting it's insulating coating and shorting out.

About too much power. Your speakers will always get enough power in the form of a clean wave (at least electrically). You still can overheat your voice coil with too much power, but usually before that, your speaker reaches it's maximum physical travel limits (back and forth movement) and bottoms out (that hard WHACK) sound.

With too little power, you clip your amp, overheat your voice coil. It's harder to hear (the bass sounds a little "off" but you don't know why). And if you're cranking it, it's harder to hear the subtle sounds of clipping.

I used to sell home audio, car audio (during the birth of big systems) and do pro audio a while back. We've rarely have speakers die from over amping, but many die from under amping. When I sold in the PXs on base, enlisted newbie+big JBL speakers+small receiver=blown JBLs. Musically inclined officer+small JBL speakers+big amp=satisfaction.

 

Great info! Thanks for your input. I have since installed the system and turned my gains down a little and lowered the settings on the amp a tad. My lights were dimming under heavy bass but since the adjustment, I have had no issues.