I am in the final planning stages of my stereo upgrade and I am weighing the pro's & con's of two versus three 10" free air subs in the rear. I have plenty of air space (8.9 cubic feet) and the Alpine subs I am going to only require 2.0 cf/per, so three is definitely an option.

I have been told by more than one person that three sub's just do not sound as good as two. I have been told that there is obviously more bass, but it is not as clean. I also intend to run the subs with a single 1000wt Alpine (PDX-1.1000) amp. I am planning on mounting the amps in the cabin, so having a "marine" amp is not an issue. I want to try and get everything ordered and on the way this week, any input on this is appreciated.

Two will be easier for the amp to deal with.

That is one of the things that keep coming up. Just looking for some real world feedback as to if 3 is even a reasonable option.

This amp is only has one channel (mono) it can run at 4 ohms or at 2 ohms. Your best bet is to run a 2 speaker set up, wire the 2 speakers in parallel.

You will risk damaging the the amp if you go with more than 2 speakers.

which alpine subs were you looking at?

i work car and marine audio for about 7 years, what you need to decide is what kind of bass you want, how loud you want it and at what ohm load you are going to run your amp and sub, what is the rms power on the subs and amp? if your going to run 3 subs you need to run a mono block amp capable of low impedence to make sure it will handle power, me personally i ran 2 10s because of space but 3 10' woofers would sound alot louder

I think the PDX amp is only stable at 4 or 2 ohms. I've never seen any specs at less. You would be at 1.33 ohms. The amp may not like it.

Are these the subs you're going to use????
http://www.alpine-usa.com/US-en/prod...model=SWR-M100

I'm thinking about using them on my next upgrade. They about the same $$ as JL and are rated to take more power. They are 300 watt rms free air which is about the highest rating I have seen for free air subs.

Yeah, those are the ones I want. Problem right now is that Alpine has not shipped yet. Everyone is advertising them, but no one has them in stock. Even Crutchfield is out of stock.

I think that will be the final nail in the 3-sub coffin. I do not want to run an extra amp just to have one more sub. The specs I have seen also dictate no lower than 2 ohms.

The only speakers I have ran as a group of 3 have been jl audio 10w6's with the dual voice coils wired in series and then the speakers wired in parallel at a 3 ohm load . Also, your amp doesn't care how many speakers you run as long as you keep your ohm load at or above their minimum recommendation. This can be achieved by using parallel or series wiring (or a combination of the two) based on the resistance of your speakers.

I'm not planning on adding subs till next year, so I'm safe. I also saw that Alpine is really tapping into the Marine market. Their website shows a marine version of the PDX amps as well.