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A friend of mine has 2 12" Rockford Fosgate P2 subs.

He had it all set up in a bandpass box and wired at best buy.

It sounds like complete crap so I'm going to help him build a new box. He wants to consider keeping just 1 of the subs.

I have a question about how its wired, right now the P5002 amp is bridged and the wire goes into 1 terminal in the box. On the inside of the terminal - 2 wires come off and go to each sub. What does that mean for the load that is presented to the amp? Also, how much power is each sub getting? (500 watts RMS @ 4 ohms amp)

I believe the subs are 4 Ohm SVC

is there one wire for positive and negative? if so there wired in parallel and if there svc the amp is at 2 ohm bridged. and if thats the case the amp is gonna asspload because its only 4 ohm mono stable.

ya its bridged into one wire for pos/neg - and then on the back of the terminal that goes into the box there are 2 wires hooked into it.... basically splitting the one signal into 2.

he has been running it this way for like a year. so maybe the subs are 8 ohms - which is kind of hard to believe.

could be dual 4

any suggestions on a box for these?

sealed or ported.

I was using WinISD to try and figure out a good ported box. Unless I entered something incorrectly, it was telling me i needed like a 7 cubic foot box. The manual says 1.25-2 cubic foot for ported.

What am I missing?

Is there something with winISD I need to change?

You tell it what size box you want. Then look at the graph and work from there.

Different volumes and different ports yield different graphs.

go to http://www.rockford fosgate.com

then go to woofer box wizard it`s really nice i used it to build my box
for my cerwin vegas 12`s the v max line.
just subtract the spkr displacement from the total cu.ft. and you can play with the measurments until you find the right cu. ft.

For a quick fix I also agree with the Woofer Box Wizard from
Rockford.


Tim