Rockford Fosgate Amp wiring question??

(nvip9r) · (nvip9r) **Join Date: Feb 2004** 06-06-2005, 7:44 AM

First just want to say thanks for all the help with my other dumb questions...here is another one...I have a Rockford Fosgate P3002...puts out 75W into 2 channel at 4 ohms, 150W into 2 channel at 2 ohms and 300W into 1 channel at 4 ohms. Has anyone hooked up one of these amps into 1 channel at 2 ohms? Will it damage the amp? I only have 2 speakers and they are rated at 100W RMS...I think they are 4 ohms...I can just measure that with an ohm meter? Thanks for any input

Nick

(tonality) · (tonality) **Join Date: Mar 2005** 06-06-2005, 8:22 AM

why would you only use one channel if you have two speakers? The amp's manual states that it is not stable below 4o bridged, so I wouldn't do it, especially in a marine environment. Just split your speaker connections and run them at 4ohm stereo.

Manual is here:

http://www.rockfordfosgate.com/products/ez2rockford/ModelInfo/ModelInfo.asp?ItemKey=10063520&CategoryDesc=Punch% 20Amplifiers

(bob) · (bob) **Join Date: Feb 2001** 06-07-2005, 6:10 AM

Nick, you just ran head on into one of boarders headaches. You bought an amp that puts out too few watts at the impedence you have. You dont want to run at the normal 4 ohm since youll only be sending 75 watts to each speaker and you cant run them in parallel cause the amp will overheat and eventually die if run at 2 ohms bridged??? What to do, either add 2 more speakers or buy a bigger amp.

(tonality) · (tonality) **Join Date: Mar 2005** 06-07-2005, 9:10 AM

75watts will push those 100w speakers just fine. Doesn't sound like you need any additional hardware to me, unless you're just itching to spend money. Wire them separately 1 per channel, and just make sure you tune them properly so that you're not running your amp into clipping, and you'll be fine.

(ponyh8r) · (ponyh8r) **Join Date: Dec 2004** 06-07-2005, 8:42 PM

I have a question along the same lines. I just bought 2 sets of Liquid Audio Front/Back and this amp an infinity amp. Here are the specs:

4-channel car amplifier
111 watts RMS x 4 at 4 ohms (139 watts x 4 at 2 ohms)

278 watts RMS x 2 bridged output at 4 ohms (4-ohm stable in bridged mode)

front and rear variable high-/low-pass filters (32-320 Hz, 12 dB/octave)

Will this amp push all eight sony 6.5" speakers? The dealer told me they would but I don't want to get screwed here and only have 30 days to return it. I am hopeing it is good enough.

(bob) · (bob) **Join Date: Feb 2001** 06-08-2005, 5:18 AM

it will but they will each only be getting 55 watts when wired properly, you need a bigger amp

(nvip9r) · (nvip9r) **Join Date: Feb 2004** 06-08-2005, 10:22 AM

Another question is that on my Tower...I am doing it cheaply right now(until I can afford a better setup)...but used a set of Home outdoor speakers...Advent Mini Indoor/Outdoor...they were pretty good inside the home...and the paperwork say they are 8ohm...but when I ohm them out through the connector it reads 4.2 ohms...doesn't make sense to me unless something happen to the wiring...but also I know that there is a crossover built inside it so would that change the Ohm reading...especially when I start pushing SINE waves through it? Thanks for any more help

(bob) · (bob) **Join Date: Feb 2001** 06-09-2005, 6:02 AM

Not sure about those particular speakers but generally using a meter will give you a close idea of what the impedence is. It will not be exact as the meter is really just measuring a piece of wire and there are formulas for calculating impedence. Does it say right on the speaker what the impedence is or was it on paperwork with them?

(nvip9r) · (nvip9r) **Join Date: Feb 2004** 06-09-2005, 11:29 AM

Here is something similar to what I got...I got black ones:

http://www.jr.com/JRProductPage.process?Product=3978038

The say 125WRMS max...55Hz->22kHZ +/-3dB
Nominal Impedance of 8 Ohm

They sound great in the house...but want to hook them up right to maximize the amp I am using...thanks for the help...