2ohm vs 4ohm?

[98stang6]

Hey guys whats up? Can someone please explain to me, the difference between a 2ohm subwoofer and a 4ohm subwoofer? im looking into a JL audio 12" W3 sub and the 2ohm and 4ohm versions cost exactly the same.

I already have an 12" Alpine Type R sub (4ohm i believe (it has 2 sets of positive and negitives on the sub itself) and im powering it with an ALpine MRP-M650 mono amp. (600 watts RMS at 2 ohms / 400 watts RMS at 4 ohms ... i think)

The thing is i want to mount the sub facing upward where the spare tire goes.. but the type R is way too tall. JL's are a great deal smaller if i remember right. so i want to switch.

my question(s) is what would be the better sub (2ohm or 4ohm) using my amp??

thanks alot for any help guys. ill try and get some pics tommorow cuz im probably going to put the type R and ported box up for sale.

 

[98stang6]

bump. please guys help me out here. matt where you at???

 

[98stang6]

no one knows anything about this...??

 

[Foster98GT]

I cant say for sure but Ive always believed the ohms meant no difference in speaker. Its all about what ohm your amp can handle. When you connect different ohm speakers they present different ohm loads for your amp, also the more speakers you add to one amp can change the ohm load as well. What you need to know is what ohm load you want your amp to run and which ohm speakers will make your amp work at that ohm.

You have a Mono amp(1channel) If you want your amp to put out 600watts you need speakers that will put a 2ohm load on it.
If you want it too put out 400watts the speakers need to give it a 4ohm load.

The Alpine sup sounds line its a dual voice coil speaker, which basically means it can be wired a couple of different ways to present different ohm loads.

 

[justinschmidt1]

Its just a differant load...for example..if you have a amp running bridged at 500 watts at 4 ohms.. you need a dual voice coil 2 ohm sub to make it work....head over to caraudioforums.com and ask for help there.

 

[Foster98GT]

Take a look here http://www.rockfordfosgate.com/rftech/woofer_wizard.asp. Its should help.

 

[Quick96Mystic]

Okay, you're better off with the 2ohm sub, you can't run anymore efficiently than 4 ohms.. the more power you can get out of 4 ohms the better

If you drop the ohms to 2ohms you're running your amp a little below efficiency but your sub will be running efficiently yet near it's peak

If you're gonna be doing competition, drop the sucker down to half a ohm and blow the shit out of your equipment :bunny3:

Hope that helped.. i kind of suck at explaining things :comando:

 

[Matt94GT]

if your buying one sub go for 2ohm, its more user friendly and easier to find an amp for and usually most are setup more benifical to a 2ohm.

 

[stangs4life]

Ohms are your load resistance.

Speakers and Amps need to be matched for optimal performance.

Using the formula R1+R2+....Rn for series circuits and (R1*R2) / (R1+R2) for parallel circuits We see that:

In series: (2) 4 ohm speakers would yield 8 ohms resistance. Series in this instance is

Amp + ---- +speaker R1 - ------ +speaker R2 - ----- \ In a series circuit the negative lead of the first speaker
- -----------------------------------------------------/ connects to the positive of the second.


Parallel gives us 4 ohms of resistance.

+/----------- + speaker R1 - ---\ In a parallel circuit both the positives of the speakers would be connected
AMP -\\---------------------------------/ to the same positive connection on the amp. The negatives follow the same pattern.
\\--------- + speaker R2 - ---\
\-------------------------------/

Understanding this, allows for some flexibility in designing the system.
I.G. We have been given a 4 ohm amp, but we already have a pair of 2 ohm speakers, we could run them in series to match the amps load requirements.
By the same idea if the cases were reversed (2 ohm amp and 4 ohm speakers) we could run them in parallel to match the load.

If the load is not correct, amp and /or speakers can be damaged.

This is by no means a 'be all end all' post. In designing the circuit, you have to consider things like: power out put of the amp (both nominal and peak), nominal and peak power requirements of the speakers and a host of other requirements.

I know the post is late for this question and the art work is bad, but may be it'll help someone.

Lee

Carpe Diem - Seize the Moment, Enjoy the Day!

 

[[NIGH7MAR3]]

the higher the ohm the more itll sound like a speaker the lower the more itll slam

 

[Shocker98GT]

The impedance (ohms) simply determines what load your amplifier will see, thus how much power it provides. 2 ohm is half the resistance of 4 (duh) meaning your amplifier will provide it with more power.

The only real advantage to having a 2 ohm speaker is that it allows you to get the power you want more cheaply. Basically it'd take half the amplifier to power a 2 ohm sub at 300 watts compared to an amplifier that would have to do the same on a 4 ohm load. Drawbacks of running 2 ohm are that the amplifier runs hotter, isn't as efficient, and has higher distortion (though realistically it's inaudible except when the amp clips)

 

[brwillms]

Impedance also changes with frequency. You have to be more mindful of that when running a lower load on your amp. Depending on your components you may have some serious issues. From my car stereo days this was only a problem with poorly designed equipment. Unfortunately, today there is a lot less design than there was 10 years ago. Most companies now build decent sounding/designed components for bargain prices. Companies like Orion and Linear Power (who made top not stuff 10 years ago) couldn't compete. They were either bought out to join the huge level of cheap components or closed their doors all together. Go to ebay, find an operational Orion 225HCCA (25 watts per channel...stable to 1 ohm bridged), find 2 good 4 ohm Dual Voice Coil subs, design a box with a Qts of about .9, wire it to the amp in parallel and enjoy. This little amp puts out a rated 400 watts in this configuration (It's a lot more than that). It has a great damping factor which arguably one of the most important factors in good Bass reproduction. I promise you you won't be disappointed.