i bought a new amp today and on the box it says x W @ 2ohm x W @ 4ohm and the power output is higher at 2ohms, so how do you choose whether you want it to run at 2 ohm or 4 ohm :/ i have no idea what it means. or is the 2ohm and 4ohm to do with the speakers? someone help an audio n00b out haha Some original photos have not been recovered yet.

what do u mean by "x W" ?? i thought that car speakers were 2ohm and house speakers were 4ohm??? not sure mayb the 2ohm is for speakers and 4ohm is for subs....? Beats me, im stumped!!! Anyone??

x just represents any number, i couldnt remember exactly what the power was. house speakers are different again i think. pretty sure they're a higher ohm

Home hifi speakers tend to be 8 ohm but some are 6, 4 etc. Car speakers are usually 4ohm. The fact that your amp specs give you a rating at 2ohms tells you that your amp is stable at 2ohms (not all of them are, and some really gutsy amps are stable at 1ohm). Your amp will be able to make more power if it's driving a 2ohm load instead of the usual 4ohm. It's mainly applicable to subs, because if you have more than 1 sub, or even if you have a single sub with dual voice coils, you can wire it for different loads to get the most out of your amp.

oh ok i getchya. thought it just had to do with speakers, cheers stevo Some original photos have not been recovered yet.

different speakers have different ohms. some different speakers can even be wired in different ways to get multiple ohm ratings from them. pretty much it means that when a speaker is drawing at Xohm it is recieving Yw of max or constant power.

EXAMPLE: Hook up a 4ohm speaker - Impedance load seen by the amp is 4 ohm. Makes no difference whether its sub or speaker same theory applys. Parellel wire 2 4ohm speakers (subs are speakers) and the total load is halfed - meaning the load on the amp is 2ohm. Series wire the same pair of speakers will double the load (4 x 2 = 8ohm) For another example lets say you have 2 dual voice coil subs and all voice coils are 4ohm. If you parellel wired the lot the amp would see a 1ohm load. You can also series the pairs of voice coils and then parellel the pairs, giving a total load of 4 ohm. Hope that makes sense i'm in a hurry!

in a perfect world an amp would make twice the power at half the ohms (e.g 100w at 4 ohm, 200w at 2 ohm )

haha i understand now fellas, cheers heaps and RB2GO: yeah matethat made perfect sense! Thanks guys! Some original photos have not been recovered yet.

To easy. Go to the12volt.com or search for ohms calculator when you purchase speakers if your worried about wiring them properly, or post back in here

Ohms Law R=V/I Resistance : R where V + Potential difference in volts Current in Amps : I The higher the Ohms the more steady the flow of electricity will be. Current is constant.

ohm stands for resistance. With a lower resistance/ohm basically means the sub/speaker will produce more db. Once I had a old 8ohm kicker sub which didn't really move much, then I brought a new kicker sub 4ohm and the mirrors where vibrating. There's a big difference between 2ohm,4ohm,8ohm. If you want a earth shacking sub go for a 2ohm. If your amp can handle 2ohm otherwise don't, 2ohm subs and some 4ohm subs put more load on the amp which make the amp hot and can cause your heat switch(protection mode) to kick in, turning your amp off.

yes thats true then you have the alpine pdx series amp which will give you the same power output at either 2 or 4ohm rating ,gotto love D Class amps :P

I reckon. In the VZ clubsport I'm running 1 x PDX1.1000 & 1 x PDX4.100. 2 x 12" type r, 4 x 6" splits & IVA502E. I have never heard a better sounding stereo. I still can't believe such a small amp can pack so much power. Go PDX!!!! PDX 1.1000 (D class amp) is rated at 2200watts 1 or 2 channel PDX 4.100 (D class amp) is rated at 880watts 4 channel