Audio/Visual & Electronics - help with ohms!

im not good with ohms when it comes to this

http://www.crutchfield.com/S-NVeRLBL6lBq/cgi-bin/ProdView.asp?i=575PL2212

would those subs and this amp

http://www.crutchfield.com/S-NVeRLBL6lBq/cgi-bin/ProdView.asp?g=120&I=489AP1200

if everything was the same ohmage i would be fine i just don't get the ohms

the subs are single voice coil 8 ohms and the amp is 200x2 at 4 ohms?

As far as I can tell, you should be fine... as long as you can wire each sub separately to each channel of the amp, since if you bridged the system, you could be over-powering the subs...
Someone with more knowledge will be along shortly to tell you any specifics about these components...

Mr^Man

crutchfield is waaaaaaay overpriced. What are your goals/budget and I can help you choose a system for your needs

Edit. Those subs can be wired in series for a single 4 ohm load on the amp. Just go postitive to positive and negative to negative.

ORIGINAL: kokasian

Edit. Those subs can be wired in series for a single 4 ohm load on the amo. Just go postitive to positive and negative to negative.


P-to-P and N-to-N is parallel, not series, which would, as you say, give 4ohms... the reason I recommended against it is because the amp pushes 600Wrms into 4ohms, and the subs can only handle 200Wrms each, for 400Wrms total... each sub to its own channel on the amp gives 200Wrms to it, which matches its power handling capacity.

(as an aside, series would be N of sub 1 toP of sub 2, then amp P to sub 1 P, and amp N to sub 2 N... which would give 16ohms total, and only about 150Wrms into the pair, if I'm not mistaken)

Mr^Man

You should read throught THIS (http://www.bcae1.com/)website. It has everything you should need to know. Also since you are sketchy on Ohms law, there is a great tutorial on there.

just so everyone knows, if you bridge a 2-ch amp with 2 subs it actually splits the ohm load causing it to be cut in half one more time than most people think. for example. 2-8 ohm subs wired in parallel comes out to 4 ohm, then when bridged on a 2 ch amp is cut in half again to 2 ohms. a lot of people dont take into effect that bridging 2 subs cuts it in half again. 1-8 ohm sub would run at 4 ohm on this amp, while 2 will run at 2 ohm

so those subs on that 2 ch amp will run at 2 ohms if it is parallel and bridged, and will allow for the most efficiency of the amp. so those subs would work great with that amp. since the amp will push 300 rms per channel, and the subs have a power range of 50-400 rms.

but also i agree with kokasian that crutchfield is overpriced, so i would look around before i bought from them

plus 2 12" subs...WAY overkill IMO

should i just go with 1 12" i was thinking that too

and so are u saying that if i did get those subs and amp that i could just run each speaker on its own channell and it would be working at full RMS power

i have an 80x4 amp for my speakers so i want bass to match that good how many watts u thinks hould be good

ORIGINAL: Sigracer10

just so everyone knows, if you bridge a 2-ch amp with 2 subs it actually splits the ohm load causing it to be cut in half one more time than most people think. for example. 2-8 ohm subs wired in parallel comes out to 4 ohm, then when bridged on a 2 ch amp is cut in half again to 2 ohms. a lot of people dont take into effect that bridging 2 subs cuts it in half again. 1-8 ohm sub would run at 4 ohm on this amp, while 2 will run at 2 ohm

so those subs on that 2 ch amp will run at 2 ohms if it is parallel and bridged, and will allow for the most efficiency of the amp. so those subs would work great with that amp. since the amp will push 300 rms per channel, and the subs have a power range of 50-400 rms.

but also i agree with kokasian that crutchfield is overpriced, so i would look around before i bought from them


ummm...ok... does someone need to read and understand ohms law.....please explain how bridging a amp cuts your ohm load in half... all bridging a amp is combinding two channels together for one output equal to
the sum of both channels...it does nothing to the resistance of your coils...

when a 2 channel amp is bridged it actually sees half the load of the subs. so when the sub load is 2 ohm, and the 2 ch is bridged, then the amp actually sees 1 ohm per channel. if you want to see some formulas that prove it, i don't have any for you, i'm going off of what every good installer, that has ever taught me anything, has told me. and if you go talk to any good installer, and i mean a GOOD installer not just any installer at an electronics store, they will tell you the same thing


ORIGINAL:03civiclxcoupe

and so are u saying that if i did get those subs and amp that i could just run each speaker on its own channell and it would be working at full RMS power


and to answer this, those subs would only run at the best performance if both subs are wired in parallel (meaning the positives and negatives share a terminal) and bridged across the amp

you just proved your previous statement wrong....1 + 1 = 2... if each channel sees a 1 ohm load thats 2 ohms combined when bridged which is your ohm load coming from the subs to begin with so what was your point to begin with.....

i think what your trying to explain is that there is more than one way to make a 2 channel amp act like it's bridged.... if your amp is 4 omh stable bridged and you have 2 dual 4 ohm subs you run them in a series parrallel to get a 4 ohm load...or you could parrallel each sub resulting in two 2 ohm loads and run the amp in stereo...and get the same amount of power.. i'm not trying to argue with you ..i think it just wasnt explaind very well

Just use this: http://www.the12volt.com/caraudio/boxcalcs.asp

You're correct. Bridging the amp does not effect the ohm load. I've been installing for quite some years and if my install experience doesn't prove me right; my certifications should. Not to argue with anyone... you just have to make sure you're adding the numbers up correctly or you can blow up your gear.

I'd stay away from crutchfield, they're over priced.