sub help

[mk5 pimp]

hi all my mate is selling me his apline 12" type r sub and im going to run it with a apline v12 mrd300 amp. the problem is that the sub is 4 Ohm and iv seen ones that are 2 Ohm can enyone tell me the difference.
thanks

[KarlM]

The ohm rating is the subs 'impedance' (sp) - basically how much power (volts wise) it can handle. you really need to speak to your local ICE dealer about ohms as its quite a complicated matter

[neilw]

That'll work fine.

basically if ur sub ohm'age is higher than what the amp says it ok to run

2ohm subs tend to have 2 4ohm voicecoils (dual voicecoil or dvc) you need a 2ohm stable amp to run these (which i expect that amp is)

starts getting complicated when you have more than one sub running from a single amp!

[Ice]

Here is a little nice wizard to help you out:
http://www.rockfordfosgate.com/rftech/wiringwizard.asp

[markd]

hi. the impedance of the sub is basically telling you the loading that it puts on the amp. its nothing to do with the power rating of the sub. say you have an amp that will put out 100w@4ohm. thats a hundred watts of power going into one 4ohm sub. if the amp is 2ohm stable, it will probably put out 200w@2ohms. by lowering the impedance, you allow more current to flow through the circuit. an example of this would be adding another sub to your system. wire it in parallel, so that both +'s from the subs go to the + terminal on the amp, and both -'s go to the - on the amp. so you have 2 4ohm subs running from the amp in parallel. 4 divided by 2 is 2. so you now have a 2 ohm load. if the amp is 1 ohm stable, it means that the amp will handle a much higher load(i.e more subs or lower impedance). so you could run 4 x 4 ohm subs off one amp, all in parallel, making a 1 ohm load. that would be 400w@1ohm. compare impedance to the flow of water in a pipe. if you make the pipe twice as wide, twice as much water can flow. impedance is a measure of how NARROW the pipe is, so the higher the impedance, the less current can flow.