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Panda Cub
03-11-2011, 09:43 AM
Are there any people out there that run more than one sub in a PS 190 or sn 196 closed bow? I am in the process of building a stereo, and I feel I only need one sub because I mainly listen to rock and country. My fiance listens to some rap, but not enough to put a ton of subs in.

Would having more than one sub be obnoxious? The lake I mainly ski on is a very quiet lake and I do not want to be a nuisance to the locals who live on the lake....... Seeing as I get enough dirty looks from skiing and not fishing.

Any subwoofer opinions would be greatly appreciated!

EarmarkMarine
03-11-2011, 11:00 AM
I'm absolutely positive that it only requires a single subwoofer if its designed and executed correctly...no matter what your expectations are.
While this may not apply to your particular boat, asymmetrical locations, boundaries, distances and orientation result in phasing conflicts. And they're very complex to predict and correct if you can correct them at all. Its a lot different with the lower frequencies and longer waveforms reproduced by subwoofers versus dealing with fullrange coaxials.
Use only the most optimum location. All separated secondary locations will be a compromise and you are not likely to enjoy double the output of the primary location for double the investment in sub and power. Will you still get an increase? Sure. Of course this is a generalization and there are exceptions. Two side-by-side subs, with the same orientation will couple and sum very effectively. And, oftentimes you have to take what a particular boat gives you.
There are many means to get the most from less. The best location and orientation. Bass-reflex produces an extra 3 dB output (equivalent to doubling your amplifier power) in a well-damped sound quality alignment...a little more with a peaky design. A lower mass and more responsive woofer rather than a singular focus on power handling. A more efficient amplifier. Good line voltage. Tuning the system for a boat rather than like a car. Thats the short list.

David
Earmark Marine

flipper
03-11-2011, 11:02 AM
I have one 12" in the bow of mine. It's plenty if you get a good one

aaron.
03-11-2011, 11:17 AM
i only had one 12" in the bow of my 190 too, it was solid. i agree with earmark in that one quality sub and amp will sound far better than multiple sub-par devices.

east tx skier
03-11-2011, 12:28 PM
I'll speak for the closed bow Ski Nautique. It's a little different than the 190 under the bow. There's what's commonly referred to as the "hump," which is really a shelf on the starboard half of the bow compartment that is about 1' taller than the port side of the compartment. This is nice for keeping your amp and sub dry and separated from all of your gear, but makes for a tight fit for the sub box.

I have a 0.38 cf sealed truck box with a Polk MM840 in it firing toward the starboard hull and it sounds very good; not earth shattering, but accurate. It's location, which is about 1.5' from the starboard hull behind the helm where there is plenty of ventilation into the cockpit from the bow, helps a great deal.

The real restriction for a sub box my boat is the height of the box, which can't be more than 11" in that location. Down firing might be a better option for larger subs if you don't want to build a box to replace the driver's kick panel. Best thing to do is figure out how large of a box you can put in the desired location and, then, go shopping for a sub that will perform its best in that box (advise stolen from David at Earmark).

These picture will give you some idea of how tight a squeeze it is and what the "hump" looks like (the angle is terrible because I didn't want to unload the gear to snap them). The wires are a bit of a mess at the moment, but that's on my to-do list. The amp is mounted to a board that is mounted to the back of the box.

https://lh4.googleusercontent.com/_1gl9obJSimU/TWWue9JfTOI/AAAAAAAADvo/pQ1iaI2TB8U/s800/100_2294.JPG

https://lh3.googleusercontent.com/_1gl9obJSimU/TWWutZ8E-uI/AAAAAAAADvs/5nG54-nDFhc/s512/100_2299.JPG

Panda Cub
03-11-2011, 12:43 PM
Thanks a lot for all of the input! I am actually putting this in a 95 ski nautique (i know, i know). I have been talking to a lot of people and I think I would like to put either 2 10" polk subs or one 10" bazooka bass tubes.

I definitely agree on putting in quality equipment. I do not want to have that flat bass sound that I hear blasting out of the "gangster" cars. I'm looking for the punchy bass sound that will sound good while listen to the entire 1984 van halen cd on repeat!

Anyone have any experience with the bazooka bass tube? I have personally only heard the best reviews on it.

Starshack
03-11-2011, 01:08 PM
I put this 10" Kicker which comes in a very durable plastic enclosure in my PS 190. Firing downward in the bow cubby. I set it up downward mainly to protect the cone from damage - it comes with brackets that set it a few inches up off the floor. I takes up space but we ski off the dock so storage is not an issue. It is powered by a high end 5 channel Kicker Amp. I considered also mounting it as a driver's footrest but it cramped up the foot space too much - not sure about the room in a Nautique.

http://www.kicker.com/skm10

josepcedwards
03-11-2011, 01:14 PM
I put this 10" Kicker which comes in a very durable plastic enclosure in my PS 190. Firing downward in the bow cubby. I set it up downward mainly to protect the cone from damage - it comes with brackets that set it a few inches up off the floor. I takes up space but we ski off the dock so storage is not an issue. It is powered by a high end 5 channel Kicker Amp. I considered also mounting it as a driver's footrest but it cramped up the foot space too much - not sure about the room in a Nautique.

http://www.kicker.com/skm10

How does that kicker sound??

eficalibrator
03-11-2011, 01:22 PM
Like they mentioned above, the quality of the sub and enclosure make the biggest difference first. I've never really been impressed by prefab, "one size fits all" tubes. Properly done, a good single sub will sound better than a pair of mediocre dual subs. BTDT.

Another thing to consider is that if you place the sub in a corner (the bow of the boat is a giant V-shaped corner), you'll automatically get a bunch of gain from the natural horn loading of the hull. You might be surprised by how much output you can get from a single 10" in the right box that takes advantage of the natural cabin gain of the expanding area of the bow as it plays toward the helm or rest of the boat.

east tx skier
03-11-2011, 03:42 PM
Thanks a lot for all of the input! I am actually putting this in a 95 ski nautique (i know, i know). I have been talking to a lot of people and I think I would like to put either 2 10" polk subs or one 10" bazooka bass tubes.

I definitely agree on putting in quality equipment. I do not want to have that flat bass sound that I hear blasting out of the "gangster" cars. I'm looking for the punchy bass sound that will sound good while listen to the entire 1984 van halen cd on repeat!

Anyone have any experience with the bazooka bass tube? I have personally only heard the best reviews on it.

I have experience with the smaller Bazooka tube that came with my boat. I would suggest you go for a different type of enclosure in a 95 SN. At first glance, they appear to be real space savers. But the fact is, on the hump, they are going to have a similar footprint to a small, wedge shaped box. You might be able to use one if you mounted your amp to a board on the port side under the bow, but if you go that route, you can use the entirety of the hump to hold a low slung box. If you're going to run 2x10", I'd suggest building some sort of downward firing setup or doing what I often hear David at Earmark suggesting, go with a single 10" in a tuned bass reflex enclosure.

As for the Polk subs, I've been really happy with the Master Monitor series. The single 8" I sounds much better than some other 10s I have heard. The price of the 10" MM series is around $100.

east tx skier
03-11-2011, 03:50 PM
Like they mentioned above, the quality of the sub and enclosure make the biggest difference first. I've never really been impressed by prefab, "one size fits all" tubes. Properly done, a good single sub will sound better than a pair of mediocre dual subs. BTDT.

Another thing to consider is that if you place the sub in a corner (the bow of the boat is a giant V-shaped corner), you'll automatically get a bunch of gain from the natural horn loading of the hull. You might be surprised by how much output you can get from a single 10" in the right box that takes advantage of the natural cabin gain of the expanding area of the bow as it plays toward the helm or rest of the boat.

In this specific bow layout, I tried this configuration and did not get as good of results as I am getting firing toward the starboard hull. It is quite possible that I had enough junk crammed under my bow that it didn't allow for proper radiation off the nose. Or it may be that the 190's even underbow storage versus the 50% hump of a SN makes a difference in this regard. It might also be that unless the port side of the enclosure is as well ventilated in the SN as is the starboard side (driver's kick panel has a good amount of open space above it), that a lot of the sound is radiating down a side of the underbow compartment where there is no place for it to escape.

This (aiming the sub at the nose/corner) was one of the first configurations I tried based on the advise of another 190 owner. For any number of reasons (some of which might not apply here), it didn't work as well.

jraben8
03-11-2011, 03:50 PM
I actually used an 8" Bazooka Tube in the elevated walk way between the windshields of my last 195 SS simply because it fit perfectly and sounded amazing in that space.

1985 Skiier
03-11-2011, 05:38 PM
A sub set up correctly should be annoying to those who do not like bass. It is up to us to play loud bass as to not upset the neighbors.

I built my box to the largest dimension that would fit and allow wakeboard ski etc to fit under the bow. Then I had to cut the box into three pieces to actually fit it in the location that I wanted it. I pre-drilled the wood and used platic inserts to assure the screws held. I also used silicone to ensure an air tight fit when I reasembled it. This allowed me to get a 12" sub and a very big box in a tight spot. 1800 watts to one 12" sub sounds killer with the correct size box, vent, etc. do your home work for appropriate demensions. I did end up with a pretty sore back after the install.

EarmarkMarine
03-11-2011, 11:55 PM
Here is a little perspective on a closed bow.
If you place a home speaker against the wall you will pick up +3 dB of gain in the lower frequencies. If you place it against the wall and floor you can expect a +6 dB gain. If you place the speaker in the corner at the floor you will get +9 dB gain. That is equivalent to 8 times the amplifier power.
So you can just imagine the bass reinforcement and boost you will get from a woofer tucked into the forward 'V' of a closed bow. An 8" woofer should easily have the output of a 10" and so on.
Forward firing into the front corner of the bow will be most effective for deep bass. This places the woofer's output and the reflected output from under the bow in phase. A 10-inch woofer should be no closer than 4 or 5-inches away from any surface. Use this 40 to 50 percent rule for any size speaker.

David
Earmark Marine

east tx skier
03-12-2011, 12:26 AM
Here is a little perspective on a closed bow.
If you place a home speaker against the wall you will pick up +3 dB of gain in the lower frequencies. If you place it against the wall and floor you can expect a +6 dB gain. If you place the speaker in the corner at the floor you will get +9 dB gain. That is equivalent to 8 times the amplifier power.
So you can just imagine the bass reinforcement and boost you will get from a woofer tucked into the forward 'V' of a closed bow. An 8" woofer should easily have the output of a 10" and so on.
Forward firing into the front corner of the bow will be most effective for deep bass. This places the woofer's output and the reflected output from under the bow in phase. A 10-inch woofer should be no closer than 4 or 5-inches away from any surface. Use this 40 to 50 percent rule for any size speaker.

David
Earmark Marine

David, does that assume an open space with plenty of opportunity for the sound waves to resonate within the compartment?

EarmarkMarine
03-12-2011, 10:08 AM
Those comments are a generalization based on the bass energy propagating unimpeded from the woofer. If there were to be large obstructions in the path or very different conditions then the approach could change. The idea in an open boat is to get all the acoustic reinforcement and leverage you can get while avoiding any situation that would add a resonance mode or phase cancellation. But a towboat is a very imperfect audio environment so you have to take what the boat gives you and accept the best compromise situation by situation. Its kind of like choosing the leper with the most fingers.
I don't want to get too deep into acoustic theories but here are a couple of examples that more can identify with or have personally experienced having a big audio system in their car. Ever turned the sub enclosure around and away from you toward the rear of an SUV or hatchback and got more bass? Ever put your nose directly against the windshield and experienced a dramatic increase in bass pressure? Ever rolled down the window or popped the trunk and actually notice the bass increase a little in the cabin? There are very defined and predictable reasons for each of these results.

David
Earmark Marine

east tx skier
03-12-2011, 11:00 AM
That makes sense. Thanks.

TX.X-30 fan
03-12-2011, 11:14 AM
That makes sense. Thanks.




I got lost too..............:D

1985 Skiier
03-12-2011, 12:16 PM
If you have a bunch of stuff under your bow (like we all do) it does not work! Stuff a bunch of towels, life vests, beach bags (you get it). point the sub toward you in the correct box or tube if you plan to use the bow for storage. I pointed my tweaters at my my windshield and wow point them in the air and you barely hear them.

EarmarkMarine
03-12-2011, 12:52 PM
Highs are increasingly directional as you raise the frequency. This doesn't begin to apply to bass until you get into the upper midbass region. Lower frequencies are omnidirectional and are comparatively very fluid in their transmission. With woofers we have a different set of concerns. Placing the woofer up in the very nose of the bow gives you that horn effect if the path is relatively unimpeded and there isn't alot of absorbing storage items. Placing the woofer just forward of your feet can create a situation where the bass energy reflected back from the large bow cavity can be out of phase with the woofer's radiation. The distances and cavity size will determine the frequency area affected and the severity. So, before you commit and permanently mount your sub, trial and error a bit.

David
Earmark Marine

TX.X-30 fan
03-12-2011, 02:55 PM
So, before you commit and permanently mount your sub, trial and error a bit.David
Earmark Marine



That is what all the home theater pros say, good luck with the wife though.........:D

Kyle
03-14-2011, 10:34 AM
I got 1 JL audio w6 under my bow. Its in a pro box because that box fit where I wanted the sub and it was the correct air space. I also have the proper amp for the sub. Everyone asks how many 12"s do you have or do you have a 15". I laugh and say 1 12".

David is right about the magnification of sound under the bow. If you don't want the "Gangster Bass" then simply don't listen to "Gangster Music". Wire an amp up that you will be using. Then take the boat down to the stereo shop and throw different boxes under the bow and find the sound that satisfies you. Then say I like that one and either have it installed or buy and install yourself.

Panda Cub
03-14-2011, 10:43 AM
Appreciate all of the input, I can you all updated on the stereo build over the upcoming weeks.

Patrick Hardy
03-17-2011, 03:16 PM
[QUOTE=Kyle;738788]I got 1 JL audio w6 under my bow. Its in a pro box because that box fit where I wanted the sub and it was the correct air space. I also have the proper amp for the sub. Everyone asks how many 12"s do you have or do you have a 15". I laugh and say 1 12".


In my 1996 PS 190, I took a easier route, old school Kicker 10C124 Comp 12" 4-ohm Free-Air subwoofer mounted to a board up in the bow on the drivers side. People also can not believe that I only have one bass.

TayMC197
03-17-2011, 04:53 PM
Thanks a lot for all of the input! I am actually putting this in a 95 ski nautique (i know, i know). I have been talking to a lot of people and I think I would like to put either 2 10" polk subs or one 10" bazooka bass tubes.

I definitely agree on putting in quality equipment. I do not want to have that flat bass sound that I hear blasting out of the "gangster" cars. I'm looking for the punchy bass sound that will sound good while listen to the entire 1984 van halen cd on repeat!

Anyone have any experience with the bazooka bass tube? I have personally only heard the best reviews on it.

I have a 10" alpine marine, I have it under the bow under the cockpit.. so its right at my feet when I'm drving. its not in the way and delivers a lot more sound being able to face out as it does.

carlsonwa
03-21-2011, 11:01 PM
I currently have a closed bow boat and have a 12" Infinity sub in a sealed box under the bow. I would like to install below the steering wheel facing out. Anyone have any recommendations for sealed or ported enclosure for this area??

thanks,
wayne

TayMC197
03-22-2011, 09:16 AM
I currently have a closed bow boat and have a 12" Infinity sub in a sealed box under the bow. I would like to install below the steering wheel facing out. Anyone have any recommendations for sealed or ported enclosure for this area??

thanks,
wayne

Shouldn't really matter, under the steering wheel doesn't get that wet.. I have mine there in a wood enclousure and it never gets wet...