Subwoofer for Sailboat 22' (Ensign)??

[dellaseppes]

Would anyone have advice for building a subwoofer for a sailboat? Its a Pearson Ensign (in case there are any sailors out there). I built the mainspeakers (located in the stern of the boat)with the 50c NSBs from partsexpress, and the comprable 50c Onkyo tweeters ... they are in a sealed box (2 NSB's runing in parallel). They sound much better than I expected. Anyway I would like to build a subwoofer for the boat, placing it in the cabin. I made the primary speakers sealed due to humidity/moisture concerns as well as the fact that I wanted a smaller box. How much bass do I need for the boat? I want the bass to be appropriate for the music, not blaring continueously ... Also another factor to consider... the system has to run for several hours on a single car battery ... We have no generator on board, so I guess it would have to be relatively higher efficiency. The NSB's in parallel are very efficient - I'm running those off of the internal 18w/channel amp in the headunit. So any advice would be great in terms of driver size, sealed or vented, regular or isobaric configuration etc .... I have various amps that I could use to power ... 2x45w sony bridgable, 2x65w sony bridgeable ..

Thanks in advance!

 

[indoubt]

Just been selecting a sub for a friends boat.
Selected Intertechnik MDS08. This is an 8" Kevlar cone car sub with very modest housing requirements and a very low Fs combined with relative high sensitivity.

I've used the unit before in a small music sub and it works very very good. No high SPL due to limited Xmax but very good sound

 

[tubesguy]

Hey -

A blast from the past. Used to crew on an Ensign that raced on Lake Michigan, out of Milwaukee. Crazy skippers that were all dentists and lawyers, so they had to be macho. Never cancelled a race, no matter how bad the weather. I'll have nightmares tonight. - Pat

 

[chipco3434]

The BIG lake isn't for the faint of heart. It can bite you right on your tweeter! DIY stereo season is almost over and then I visit my little mistress! I'm 20 minutes from the house to being out of the harbor and on the lake ~100 days a year.

You can mount the speaker behind a deck plate...

http://www.shipstore.com/ss/html/BEC/BECDP60B.html

up to 8" on the screw outs.

Here's my little sweety

sailing through the lee of some sluggo slop bucket

 

[dellaseppes]

Thanks for the Advice, what are the general T/S paramters that I would be looking for since Intertechnik speakers I can not find easily. I would prefer to stick with something from partsexpress.com (and something modestly priced ... You mentioned low Fs and high relative sensativity. I am now considering putting the unit under the teakfloor boards where you can see the keel ... I could probably fit an 8" tube (perhaps I could put a woofer on each end going isobaric, or a larger 10/12" facing down (so it does not collect water). Perhaps I could even put 2 facing down .. would i run parallel or isobaric? I was looking at these cheaper Pyramid 10" subwoofers for $17 each (description below)
"
These classic quality, high-power drivers feature a white polypropylene cone that adds a distinctive look to any installation. Feature strong strontium magnets for high power handling, specially designed rubber surrounds, inverted-style dustcaps, and bumped back plates for extended excursion. Two year manufacturer's warranty.
* Power handling: 175 watts RMS/350 watts max * Voice coil diameter: 1-1/2" * Impedance: 4 ohms * Re: 3.22 ohms * Frequency response: 40-3,000 Hz * Magnet weight: 70 oz. * Fs: 40.1 Hz * SPL: 92 dB 2.83V/1m * Vas: 1.748 cu. ft. * Qms: 2.35 * Qes: ..74 * Qts: .56 * Xmax: 3.55 mm * Manufacturer model number: WX102X * Net weight: 5-1/2 lbs. * Dimensions: Overall Diameter: 10", Cutout Diameter: 9", Mounting Depth: 3-3/4", Magnet Diameter: 4-3/4", Magnet Height: 1-1/4".

Or was considering these $34 pioneers ...

Power handling: 70 watts RMS/100 watts max * Voice coil diameter: 1-1/2" * Impedance: 6 ohms * Frequency response: 26-2,500 Hz * Magnet weight: 30 oz. * SPL: 93 dB 1W/1m * Vas: 6.07 cu. ft. * Xmax: 2.9mm * Qms: 3.36 * Qes: .21 * Qts: .20 * Fs: 26 Hz * Net weight: 6 lbs. * Manufacturer model number: A25FU30-51D * Dimensions: Overall Diameter: 10-1/8", Cutout Diameter: 9-1/4", Mounting Depth: 5", Magnet Diameter: 4-3/4", Magnet Height: 1-3/4".

Again any advice would be appreciated ...

 

[chipco3434]

I really think the cabin sole is the last place to place these. Just too damp and exposed to water from bilge. Isn't there a wated space between lazarettes and the transom?