amp impedance

minime122 · 03-08-2005, 05:15 PM

I've got a question that im probably gonna feel stupid for asking but here it goes. Im purchasing a Rockford Fosgate P210S4 10 inch sub its power range is 50-200 watts RMS with its peak power being at 400 watts it has a 4 ohm impedance. I need to know what kind of amp to buy for this sub. Im going to use a mono subwoofer amp. All the ones i see are rated for 2 ohm impedance i know ill need the amp to be at least 200 watts but does the 4 ohm impedance mean that i need to find an amp that can put out 4 ohms?

410Fortune · 03-08-2005, 05:37 PM

yup, they must match.

Now your amp may be able to handle a 2ohm load but that doesnt mean it cant also handle a 4ohm load, it just wont be as powerful.

You see a 2ohm load on the amp just draws more power, forcing the amp to make more.
Now if you hook up a 2ohm speaker to a 4ohm stable amp = toast.

You can also wire two 4ohm speakers together to create a 2ohm load, thus usually doubling thepower output of the amp, so if you buy a 2ohm stable amp now you can upgrade later.

Most good amps on the market today are 2 ohm capable, some even lowed, 1/2 ohm WOW....

davesexplorer · 03-09-2005, 10:51 AM

A good option for you then would be a 2 channel amp, most are bridgeable to 4 ohms mono - perfect for the single 4 sub.

Or dont rule out the 2 ohm stable amps, if you get a 2 ohm stable amp it will allow you headroom if you choose to add another sub or even upgrade to a dual 4 model etc. Just look for what you need @ 4 ohms.

03-08-2005, 05:15 PM	#1
minime122 Wannabe Elite Explorer GA '01 sport Join Date: Oct 2004 Posts: 15 Vehicle Specs (Original Poster)	amp impedance I've got a question that im probably gonna feel stupid for asking but here it goes. Im purchasing a Rockford Fosgate P210S4 10 inch sub its power range is 50-200 watts RMS with its peak power being at 400 watts it has a 4 ohm impedance. I need to know what kind of amp to buy for this sub. Im going to use a mono subwoofer amp. All the ones i see are rated for 2 ohm impedance i know ill need the amp to be at least 200 watts but does the 4 ohm impedance mean that i need to find an amp that can put out 4 ohms?

03-08-2005, 05:37 PM	#2
410Fortune ELITE BRONCO2ERER Crawlorado B2 Mod Join Date: Aug 2000 Posts: 22,099 Vehicle Specs	yup, they must match. Now your amp may be able to handle a 2ohm load but that doesnt mean it cant also handle a 4ohm load, it just wont be as powerful. You see a 2ohm load on the amp just draws more power, forcing the amp to make more. Now if you hook up a 2ohm speaker to a 4ohm stable amp = toast. You can also wire two 4ohm speakers together to create a 2ohm load, thus usually doubling thepower output of the amp, so if you buy a 2ohm stable amp now you can upgrade later. Most good amps on the market today are 2 ohm capable, some even lowed, 1/2 ohm WOW.... __________________ 96 Explorer daily driver build-1996 XLT 5.0L AWD to 4x4 conversion complete on 33's 88 BII 5.0L conversion - BII 5.0l drivetrain thread My Bronco II - 1988 Bronco II 4x4 V8 on 35's - registry and updates Wifes 07 FJ build - 2007 FJ cruiser locked and lifted

03-09-2005, 10:51 AM	#3
davesexplorer Wannabe Elite Explorer Central PA 2001 F350 7.3 Join Date: Mar 2001 Posts: 2,808 Vehicle Specs	A good option for you then would be a 2 channel amp, most are bridgeable to 4 ohms mono - perfect for the single 4 sub. Or dont rule out the 2 ohm stable amps, if you get a 2 ohm stable amp it will allow you headroom if you choose to add another sub or even upgrade to a dual 4 model etc. Just look for what you need @ 4 ohms. __________________ 2001 F350 Extended Cab Long Bed Lariat 7.3 Powerstroke 4x4 1999 Mustang GT 5spd vert