Need an Explanation of Ohms

[McCorkle]

I was reading through my Audiobahn manual and since I am going to bridge it the sub needs to be compatible between 4~8 ohms. Now what I need to know is which ohm level should I make sure my subs can handle. Is 8 ohm going to be better than 4?

[M3turboca]

Use two 8 ohm sub in parallel. Mean that you have to connect the positive of both speakers together and the negatives together. This will drop the impedance of the speakers from 8 ohm each down to a total of 4 ohm.

The amp in mono or bridge will see the load as 4 ohm and most amps are designed to load at 4 ohm unless you spent big $$ to run 2 ohm loads.

[blue LEDz]

I was reading through my Audiobahn manual and since I am going to bridge it the sub needs to be compatible between 4~8 ohms. Now what I need to know is which ohm level should I make sure my subs can handle. Is 8 ohm going to be better than 4?

the amp seeing 4 ohms will give you the maximum power. i'd get 2 dual 4 ohm subs. you'll wire them in a series/parallel combination, so the amp sees 4 ohms.

[McCorkle]

Okay so I would be set with a 4 ohm sub?

[Kevin]

here is a good link to explain the pysical wiring of the sub with diagrams.

http://www.crutchfieldadvisor.com/S-xHEt0z5HdNA/learningcenter/car/subwoofers_wiring.html?subs=2

thats for wiring of 2 subs, so if you're doing one sub, scroll down to the bottom of that link and you'll see wiring diagrams for that as well. now if i remember correctly, with your new amp, you had mentioned something about running 2 amplifiers to get 800 watts to each sub.. for a good deal of subs, this is a bit too much if you turn the gains. eyeballing everything, the specs for that amp are listed at:
Watts into 4 Ohms (Stereo): 200 x 2
Watts into 2 Ohms (Stereo): 400 x 2
to get the most out of that single amp, i'd find two 4 ohm subs with single voice coils (a single set of positive and negative leads), or two 2 ohm subs with dual voice coils (two sets of positive and single leads). that link i gave you will give you an idea of how to wire the subs. as far as what kind of wattage, the two setups i suggested will push the amp for all it's worth at a 2 ohm load, pushing out 400 watts peak to each subwoofer. as far as what to shop for as far as wattage in subs, look for something with an rms wattage range anywhere from 250 to 350 (anybody got a better recommendation)? thats just an estimate, however, i would personally recommend you check out http://www.edesignsaudio.com (elemental designs)... reliable, no frills, and highly acclaimed (http://www.soundillusions.net will give you a good idea of how many people love these subs). on top of that, many board members on here would back me up on that. at any rate, i hope this helps you.
peace

[McCorkle]

Sounds like to me the Alpine Type R's are the winner. I'd go with the dual 4 ohm 12"'s.

[asylum24]

the one thing I still dont get are ohms..... still wonder if i have mine hooked up right

(mono amp to dual 4 ohm 12" going to positive and neg. and then another wire running to the other terminals... + to +, - to -) is that right?

[blue LEDz]

the one thing I still dont get are ohms..... still wonder if i have mine hooked up right

(mono amp to dual 4 ohm 12" going to positive and neg. and then another wire running to the other terminals... + to +, - to -) is that right?

sounds like you've got all the positives and all the negatives hooked together, so that's a parallel config, so you're running a 2 ohm load to your amp