Which would be louder?

Let's say you have a 5-channel amp with a bass channel that puts out 150Wrms into 4ohms, or 180Wrms into 2ohms.

Which would be louder, one 4ohm 12" svc sub run at 4 ohms, or two 4ohm 12" svc subs wired in parallel run at 2 ohms? So one 12 with 150Wrms, or two 12's with 90Wrms to each? If it makes a difference lets say they are Infinity Reference 1220W's.

(I'm not even sure I could run the bass channel at 2ohm when the other 4 channels are being run at 4ohm - cheap Sony amp)

With a 'good' amp (not taking a jab at your SONY), I'd definitely say do 2 12's run @ 2 ohm if you have the space to install them. Personally, I'd bet a good single 12" sub run at 2 ohm off a quality amp (600 watts or so) would rock your boat pretty good. Sure does in my boat!

(Message edited by bigdeal on February 11, 2005)

I run one 12" dual voice coil 4 ohm cheap kenwood sub. dual voice coil allows you to wire to turn it into a 2ohm sub. i also run one 5 channel amp with the factory 2 way clarion marine speakers. so much bass with the right enclosure, not a lot of wattage needed. but if you really want to kill the fish, 2 12's wired in series to make them 2ohm speakers with a mono amp, 4gauge wire and a capacitor is a must!

Hmmm,

That's a question that's probably best answered by trial and error.

Your boat is not a sound room with a defined listening position. When you start running multiple subs you will probably hear different things in different locations. Remember you are hearing/feeling pressure waves, if the waves arrive in phase then they add if they arrive out of phase then they can begin to cancel each other, they all travel at the speed of sound but the wavelengths vary by frequency. I would recommend a single sub or multiple subs very close to each other. My guess is that two 12s will need to be placed in different locations? More is not always better. If you are running 2 speakers off a single amp they will split the power regardless of how they are wired (parallel=splitting current, series=splitting voltage, watts=current X voltage). Since your weakest link is probably the amp it might make sense to let it work it's best on one sub, provided you can optimize the impedence match between the sub and the amp. My guess is that your Sony will drive a 4 ohm load in mono, not 2 ohm.

Just for kicks put a top view diagram of you planned system so we can see what is going where. I will try to attach a sample, not sure if doc files show up correctly.

system diagram Stereo diagram.doc (78.3 k)