Matching Amps with Speakers RMS

Why do amplifiers have different outputs at different ohm resistances?  Do you get better SQ at higher subwoofer resistance or are these two things irrelevant?

I have a RF P8002 amp with

200 W x 2 @ 4 Ohms RMS

I currently have 2 Sony Subs (XS-L121P5)

1200 watts peak, 350 watts RMS

I can not bridge them since my amp is not stable at 2 ohm bridged.  My amp is only outputting 400 watts then.

I was thinking that If I bought 2 more of these crappie subs and bridged them to 4ohm then I would still be giving 200 watts to each speaker.  What are the differences in performance?  My amp will be working harder and outputting more power right?

I'm going to upgrade my subs.  I was told that DVC subs do hit harder and I want to stay with RF and Best Buys warranty.  I looked at the P312D4 (1000 watts peak/ 500 watts RMS).  15" are mostly used for lower frequencies and require more space; Do you think these are not good for SQ?

Do you think my amp will suffice a pair of these subs?  It's better if I buy two so I can bridge them as bellow to a 4 ohm load right.

If I want stereo sound do you think I can bridge them as bellow to each channel?  Will I still get the same power output from my amp?

What set up will give me better SQ from your experiences?

No I realized that the set up I have right now with my Xploder's does not utilize the full power of my amp.  I think best buy needs better sales people.  Thanks for your time.

Can I power these 2 DVC 12 with the amplifier I have; P312D4 (1000 watts peak/ 500 watts RMS). 

If I connect each speaker to a channel droping the ohms to 2, does it mean that aech speaker now has 1000 RMS and 2000 Peak at 2ohms?  In that case my amp would not provide enough power for the speakers right.

Should I buy these speakers or get some P2's with less RMS watts?

Has anyone heard these at all?

DVC speakers do NOT "hit harder" than SVC speakers if they are the same type and handle the same power.  The number of voice coils available are only for wiring flexibility.

Amplifiers produce voltage and have a limit to the amount of voltage they can produce.  By placing this voltage onto a resistance load (your speakers) current flows.  Changing the resistance causes different amounts of current to flow.  See Ohms Law link in the left side of this site.  Since most laymen do not understand voltage and current, "watts" (a measure of power) is the commonly used way of describing this current flow.  So an amplifier's rated power output is the number of watts produced by the current that flows at the amplifier's maximum voltage output level.

In general, higher SQ is achieved by using higher impedence loads on a given amplifier.

In general, 15" woofers have less SQ than smaller drivers but can produce more SPL at the lowest frequencies.  There are exceptions to this.

DYohn

So running an amp at a 4ohm load is better/cleaner than running it at 1ohm load, right.?

So does this mean that If I wire my DVC as the second picture above, I will actually need 1000Watts RMS to power it a 2ohm?

If so then what about the first wiring option pictured above; the amp will be presented with a 4ohm load but will the speakers combined RMS be 1000 watts or 2000 watts?

If the RMS of the speakers does change with resistance then if would be wize to wire them as the first picture shows.  If not, then I could wire them so I could get stereo sound. ( although I don't really need my bass to be stereo only to show off with some sound effect cd's) 

What would be the best set up for this system?  Should I consider getting p2's instead?

I have a RF P8002 amp with

200 W x 2 @ 4 Ohms RMS

400 W x 2 @ 2 Ohms RMS

800 W x 1 @ 4 Ohms Bridged RMS

These are the specs you gave for the amp.  The specs do not increase because you add more speakers, they remain the same.  The amp will provide 400 watts at a 4 ohm load.  800 watts at a 2 ohm load.

You make the choice whether you want to run subs at 2 ohm or 4 ohm, then buy subs with coil configurations that will wire to the load you chose.

RMS of a speaker does not change.  A speaker with dual voice coils wired in parallel has the same RMS capability as the same speaker with coils wired in series.  The change occurs to the amplifier. A lower ohm load will cause the amp to produce more power, but not as clean as the higher ohm load.

And connecting a sub to each channel, yes, is a stereo setup.  But you won't hear sub frequencies in stereo.  It will still sound mono. Stereo sound begins to occur when the frequencies get high enough that you can pinpoint the location of the sound.  Frequencies below 80 to 100 Hz are omnidirectional, in that you can't locate where they are coming from.  They seem to be everywhere at once.

Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Right.  In general.  Some amps can sustain low distortion and high S/N ratio at lower impedences, but not many.  I run my SQ setups at 8 ohms or higher.

DYohn, So does your SQ setup sound "Superb" at 8ohms?

I wonder how much my 1200.1 Kicker amps put out at 2ohm or 4ohms at 14.4v? Right now they are running at 1ohm. 

hurtado_roberto, What Stevedart said above is true but there is a difference when you set it up in stereo. Even though you don't hear what direction the bass is playing from, you do feel it  differently(provided you have monster bass) . When you play a stereo bass song you will fell your car shaking one way or the other. My second to last setup was in stereo and it would rock the car from side to side because of direction of woofers. For this to work though you cannot use your sub-out rca's from head unit because they are mono. You have to send a full signal and use your crossover/s to cut high fequencies.