Car Audio: Why are front speakers rated so much lower than rear?

[StageLeft]

$60-70 will get you some 120-160 watt peak 6.5" speakers with 80 RMS, but for the same price you get like 20 RMS front speakers - is this purely because these fronts will be handling little to no bass...? If I have the fader set to neutral will the head unit or the front speakers be the ones that automatically put less power into the low range so that the fronts are able to keep up with the rear, or do I have to spend a bunch more money for fronts that will keep up...?

Anyway I'm going to order some 4X6 from crutchfield. I have the Kenwood KFC 1677's (supposedly 160 max and 80 RMS; I know that in real world my headunit that has 45 max and 17 RMS could easily blow them though) in the rear so I wanted something similar in performance for the front...

 

[Monel Funkawitz]

For good imaging, you want highs up front, small high/tight mid bass in the doors, and big bass in the back.

Mega watt highs aren't needed. I run three JL 12W4 DVC sucking down 1041 watts in my crew cab truck, and I get a SPL around 160 depending on the tunes. I'm running 60 watt per channel each side for front highs, and door midrange. It is PLENTY. Enough that you can't listen to it all the time. I cruse around on 14 on the volume most of the time. It goes up past 50 I know. at 20 you feel like your head is going to implode. The highs are more than sufficient at that level, even with only 60 watt per speaker.

Just get some good quality fronts, like MB Quart or something.

 

[Scootin159]

highs don't take as much power to reproduce.

 

[MichaelD]

MonelFunkoWitz (the other car audio nut on this forum besides me 😀) hit it; I'll just add a little.

Typically, front speakers (doors/dashboard) are between 4 and 6.5 inches in size. Physically smaller than rear deck speakers, which are usually 6x9's. The smaller the speaker (well, the smaller the VOICE COIL, actually) the less power (wattage) it can handle.

Also, if you have a smaller speaker (like a 5 1/4 or a 6.5) highpassing it (cutting the bass out of the signal) will allow that smaller driver to handle more power.

I have Infinity Reference 6.5" separates in my front doors. They are rated at 90W RMS per pair (midbass&tweet). I have 130W RMS running to each door. Yes. I am insane. 😕 The gains on the amp are a tiny hair above 0. They are highpassed at 70Hz/24db oct. That means all freqs below 70Hz are attenuated at 24db per octave. Basically, you hear next to nothing below 70Hz out of them.

Only when I have the volume at about 90% of maximum do I hear them beginning to distort. That is way louder than I listen to it 99% of the time though.

Feel free to PM me (or ask here) if you have any other car audio questions. 🙂

ps
For Monel (cause I know he wants to know 😀) I have a single JL12W3-D2 @ 4 ohms running off a Kenwood PS-300T , 300W RMS. It's plenty loud and hits low. 1.5cf (net sealed box) LP'd at 70Hz/24db)