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Quick Rick
03-07-2004, 01:29 AM
hi guys. i was thinking of putting a 10" sub in the front of the bow. i have a 21' super boat so room is not an issue. what do you think of just glassing in a amall bulk head for the sub? also i have 2 running lights at the front which would be behind the bulk head. good idea or just dumb? thanks for any input

bulldogdaddy
03-08-2004, 01:15 PM
look in the 6x9 section on this page

Liqui-Fly
03-08-2004, 01:49 PM
If that's what you want to do make sure you get a free air sub. They are meant to perform without an enclosure.

Quick Rick
03-08-2004, 06:04 PM
i guess what a meant was to enclose the the front section of the bow. 12-14" or there abouts. but to have a sealed box, would my running lights screw it up? sorry i am 42 and don't get this stuff.

bulldogdaddy
03-08-2004, 06:12 PM
i'm 40 and took 5 yrs to figure out how to post a pic:D

Quick Rick
03-08-2004, 06:31 PM
hey bulldog, never even considered trying that yet

pyro
03-09-2004, 07:38 AM
As long as you don't need access to the bow light fixture and wiring from underneath for any reason, then that's fine. Seal up the fixture with RTV from underneath so it doesn't "blow through" and affect the sub's tuning, do all the math and get the cabinet volume right. any problem with extra weight in the bow affecting performance?

Quick Rick
03-09-2004, 07:47 PM
how do you know what volume to make a box? since the bow is a v. how critical is the size? 10"or 12" sub? heck ,i don't even know how to wire one up. in my world stereos go side to side, and i don't know why they don,t go thump, stop ,thump ,stop and miss the other half

WILDMAN
03-09-2004, 07:52 PM
I've got a 21 Rallysport, same as Superboat. I've got a 1000watt stereo in mine. I use a single 12" sub in a separate sealed subwoofer box that I just set up in the bow. Sounds great, and you can take it out easily anytime! A sealed box for a 12" should be 1-1.2 cubic feet inside.

Quick Rick
03-09-2004, 08:02 PM
where did you mount the sub in the bow? also what did you do to fasten it down? i had a couple boxes in my last boat and no matter what i did after a few rides they went flyin. i have a couple kids that like to crash under the bow so space and a foot through it is of concern. thanks Rick

WILDMAN
03-09-2004, 08:07 PM
My floor up front is carpeted, and so is the box. I buy "Q-LOGIC" boxes. The carpet to carpet does'nt slide much. You can also just put a small cable or rope to the front bulkhead to keep it from tipping over. I put the speaker all the way up front.

sho305
03-09-2004, 08:57 PM
I used a tube woofer in a car, and put velcro on the bottom so it stuck to the carpet. But in another car I had a strap with velcro...think I took it off an excercise machine that someone tossed. I screwed the strap to the car, then just strapped the tube to the side of the trunk and it stayed put. I put a trailer plug on that little one so I could take it out for a big load as it had screw terminals, but not a great idea for higher power. Getting a tube or box would be much easier, then glass in a couple mounting surfaces is all. Put some padding there if needed and strap it down. That way you can still move or remove it if you want, or use screws/etc and make it more permanent. Just an idea. With one sub I might go for the 12".

With the glassed in deal you could still get to your lights through the speaker hole if you needed, so it would work ok but be more work for you is all. Me, I would try to copy the volume of a ported box and port it(if you at lower power, 1000watts you might want sealed). It should put out a little more that way, and you can just culk leaks at wires/etc.

I also got this sticky rubber stuff you put under rugs I guess. I put a piece on the console of my truck and nothing slides around anymore:) It is kind of webbed, got it at Menards real cheap.

Quick Rick
03-09-2004, 09:25 PM
thanks for the input guys, this stereo section is great. keep it cummin

Techno
03-10-2004, 03:42 PM
Anyone who wants to build their own box.
There are several freeware programs on the web. Or get a book.
The speakers come with a spec sheet. With that sheet and the formula this tells you the speaker volume you need. These aren't must be this size things. You get a percentage slop anyway and then stuffing can make the box bigger for those areas that won't hold the correct volume.
Then there are the choices. Sealed, ported and on....
You can stick any speaker in any sized box but why? This is tuning for maximum effect.
Ported boxes are tuned using the diameter and length of the ports tube. This is a free bee using resonance to boost a small peak in the freq of the speaker. Not really needed for its complexity, unless you have to have it.
A sealed box is simple and the calculations are simple math pretty much.


I'm from the feel it school. I could have replaced the 2 -10ers with 1 -12" or whatever. But I crammed 2-12" subs in back of my Vette with the top still able to be stored there. I'm glad I did go with 2-12" air pumpin bone shakin bass makers.
Bass is meant to be felt as well as heard.:cool:
Go with as much bass as your wallet and total system can support.

sho305
03-10-2004, 04:53 PM
I agree with you Techno, more is better!

I have had some of my best sound with sealed boxes. They are easier to figure and more fail-proof; they work. They also tend to handle the most power. If you want to fiddle with tuning, you can get a little more with ports if your speakers will handle the power you are using. The port tube should be tuned to the sound you want to hit hardest. It is harder to do the smaller your box, as the small box cuts more bass off. In fact for the same tune you need a little bigger box to make up for what the port tube takes away in volume. Manufacturers like to use a smaller box, then make it back up with a port just to sell a smaller box. I use a normal size box that is easier to tune a port on, and use the port to give me more. If you don't want to play around with it, go for the sealed box! It can take a while by ear.

Port or no port, bigger boxes make more bass.:D I don't like many store boxes because they are too small. Back to being efficient, you can get good bass out of a big ported box and less amp. The smaller you go the more you have to force it out with power.

bulldogdaddy
03-10-2004, 05:16 PM
i bet you saw the movie dc cab with gary busey!where he had so many speakers in the back of his cab when he turned on the system hi shattered the window:D

Quick Rick
03-10-2004, 06:50 PM
nah did,nt see that one, but sounds good. i just got me a f150 screw and it came with the audiophile which comes with a small sub. i like it, never had me one of those things beore . hey guys, tell an older fellow what to buy for a 21' superboat to make it rock. my price range is mid point, you know 2 kids and all. thanks Rick

Techno
03-10-2004, 10:00 PM
bulldogdaddy
:D I remember that:D

Quick Rick you ask an unanswerable question. But really you only need enough of a system to please you. Most of the music I listen to if it don't reproduce extremely low bass you actually miss the music. Like that country fiddle with the devil song, take out the fiddle and whats left? Imagine the mid range speaker couldn't reproduce the fiddle and you listened to the song, what then?
If you don't listen to fiddle songs it wouldn't matter though. Or matter but to a lesser degree.


The whole concept of these "high end" systems is a speaker can't reproduce the range of human hearing all in one unit. Something like 20 hertz to 25,000 hertz. Splitting the job up into more speakers that do just a slice improves more and more. Like gear boxes. The woofers are the power gear low but slow. They use the engines maximum output.
Mids are the median, which happens to be about speech range. even in power and speed. Most of any type of music is here.
Tweeters are the speed gear. Don't need much power and very fast.
I don't know if that makes sense or not:confused:

With out knowing anything else a decent quality amp powering as large a woofer as possible is the best improvement. This is where it becomes difficult for sound to be reproduced and takes lots of power. The mids and tweeters require less and lesser power and usually do a pretty good job as is. Then these can be upgraded like adding an amp and stop using the head units over rated magical amp.

I've forgotten the frequency ranges but the speakers are
Tweeters- highest frequencies.
Mids. These go from the bottom or from the next lower speaker to the tweeters. About 6khz or something.
Thats a 2 speaker system and is asking alot from the midrange speaker. It just can't do it. The lowest freqs just aren't there, they don't exist.

Woofers. These go from the bottom or from the next lower speaker to 1khz
A 3 speaker system and is still asking the woofer to cover quite a bit of territory. Loses the very very bottom. May not be missed though.

Sub woofers. 20- 100? forgot but it varies a bit.
4 speaker system and the hardest most heavily worked speaker is limited to an extremely small range. Uses larger amounts of power and is physically large.

These spots where the speakers "touch" are the crossover points. Sub is set high at 110 the woofer is set low at 100 kind of thing.

One of the other guys can fill the actual wish ranges for these speakers. I've forgotten. But it gives an idea why a woofer improves a system so much.

Ospreyproduction
03-10-2004, 10:30 PM
I have two 10" Infinity subs in my Skater and they will rattle your retena's!!! I bought the pre-built carpeted sealed enclosures and mounted them up front well past the foot rest. They are cheap enough that building them yourself doesn't really make sense.
Sometimes your subs sound better facing you, facing away, or facing up, it all depends what the front of your boat is like. No one can tell you what will work before you listen. Try all angles before you mount them. Plus they make very heavy duty grills that can be installed to protect your subs.


P.S.
Memphis Belle Amps!!!!
Well worth the money. They are one of the few that have their true watt rating on them. The other good amp is a JL.

Good luck

Quick Rick
03-11-2004, 06:16 AM
thanks guys, i am leaning towards a 12'"sub mounted somewhere in the bow. what is a reasonable amount of power to run to it? also has anyone heard the bose 6" speakers with an enclosure that comes with them? Rick

pyro
03-11-2004, 07:45 AM
Speaking of INFINITY, they make a sub called the Infinity PERFECT 12". It is one of the most efficient subs on the market that can handle some power. This means that it can turn a reasonable amount of power into a LOT of sound pressure. I think they're rated for 350 watts, but it will POUND with much less. Consider buying a dual voice coil model and using a 2-channel amp to run it, perhaps 300 watts, (150+150.) A sub with a high efficiency rating will allow it to work its bass magic without draining your battery too much, bacause it's not as power-hungry. Most of the large, expensive, heavy subs that can handle 600 watts are so inefficient that they NEED 600 watts to get them moving. But they can hit louder than the others, though. Also, SOME of the very cheap subs are extremely efficient, but they can't handle as much power without distortion. Such would be a good choice if you had a small amp wattage to work with. Make sure you get an amp with a VARIABLE low-pass crossover feature. This will allow you to adjust the frequency point at which mids and highs are removed from its signal before it's amplified. This way, if the bass is too "muddy", you can set the crossover frequency lower. And if the bass drum kicks hard but the music still sounds thin, you can set it higher.

You can take just about any 12" sub and mount it in a sealed cabinet with an internal volume greater than 2 cubic feet, and expect good performance and efficiency.

Also, the bow is a good "acoustic" location for a sub, because it's in a corner. I'm not going into details about acoustic theory right now, but this placement will make it sound better for sure.

-Chad

Ospreyproduction
03-11-2004, 08:00 AM
If you have the space, two 10's will seperate you from a single 12 all day long.

No offence Wildman.....you do paint....and I do stereo.

Spend a couple extra bucks on a "real" amp, you will be more than satisfied. These amp companies throw 1000watts around like they are pennies, the fact of the matter is that most of the listed power wattage on amps doesn't even come close to what they really provide.


Go look at:
http://www.memphiscaraudio.com/P08&09_MClass_Amps.htm


Scroll down and look at "The Memphis Belle" amp.

1 Amplifier, 5 Channels and a ton of REAL power. There isn't a Sony, Alpine, Kenwood, Panasonic, bla bla bla that can hold a candle to one of these amps. Also comes with sub contol remote.

Ospreyproduction
03-11-2004, 08:13 AM
Doesn't need to be that big. 1CF to 1.4CF is plenty for a single 12. The sub you buy should have a specific spec on what works best for that particular sub. Most 12" subs call for 1.2 CF

sho305
03-11-2004, 09:53 AM
Well you can, but the smaller your box the faster your low frequency falls off, unless you have a sub made more for that. You need that with big power, but I'm not sure what level we are talking about here. I can buy a 300-500 pyramid amp and a two 10" or 12" in a box for $200. That would do plenty nice in a car for me. I ran pyramid $13-$30 10" subs for years and they only died when the surround rotted away. In fact the paper ones worked the best. I ran many 120(good)-300(cheaper) watt amps on them. Four of them at 2 ohms was real nice to feel.

But many of the store boxes are too small for me. Everyone wants a little box but it don't work that way; the tighter the box the less bass you get. Only needs to be tight enough to handle the power you use within reason. At 150w/channel I can run 2sq ft on each 10" for great sound, and even use ports for more thump. I doubt there is much difference in a 500/300 watt pyramid, but at higher power my tens would not handle it that is true. But I will get the max thump out of that relatively little cheap 300w amp. I'll make the box smaller until the 10s don't bottom out:D But I found that some amps have more control so you can still use the bigger box. Pyramid is not the best control amp, but worked ok. If my sub can't pull 60Htz good, it is too small. There is a reason the big old home speakers are that big. Just IMHO of course.

I once made a box that was a full 4 sq ft+ when you included the speaker structures inside. I divided it in two and fit 4 10" subs in there. It was tight at maybe 1.1sq ft per 10". I tried ports and it helped a little. I ran some various 300w amps at 2 ohms on them, still was not happy though it was loud. One day I ripped out two of the tens and the partition. Then, it shook the car better than before running the same amp at 4 ohms. With one amp I had to plug the ports to keep it from bottoming, with others I did not. I had no way of measuring really, but I paced off distance to the car and compared it to background sounds far away. I had tried stuffing it with the four, then ended with it empty and rockin' with two. I thought the tone they made was much better also.

The better stuff will do more for sure, don't get me wrong. I have some Rockford 10"s I really like. It is just that I could get this setup to do all I wanted to endure inside the car if you know what I mean. I have not done a system with one of those 5 channel do-all amps though I would like to try one. It would be nice to get away from all the multiple amps and crossover, but I figured I could not tune as well that way so I never did one. I have had a lot of problems with finding crossovers that were worth a %$#. If you get one, buy the best one you can get. I also want to try to make those tube subs work on something. They are light and easy to move/mount...great in a boat. Also only like $70 for cheap ones.

The trend in cars now that amps are relatively cheap, is to use lots of power with a crossover to force the too-small box to make the bass. I don't agree with it, but then there are times when you have to do that also. On the other end of the spectrum you have something like the bose radio with a folded tube, a wave guide I think it is called, that works like a tuned organ pipe to make good bass with a tiny speaker. I think they use a 4" sub or similiar. It is much like an expansion chamber on a 2 stroke in the way it works and enhances performance of the speaker. So I like to go as big as I can, then figure out what I can do with that space.

Considering the open space of a boat, I might try 4 tens or maybe 2 12"s for good pounding action...but most times you don't have the room. Maybe I'll get one of those tubes and do some testing on my little bayliner this spring, but I don't even know where to put one of those in there with the open bow.

pyro
03-11-2004, 10:23 AM
Sho, you have a taste for bass!! That's a lot of speakers for one set of ears! I agree about the cab volume. Despite whatever volume box the mrf. rates the speaker for, the more internal volume you add, the lower the bass rolloff is, and the more efficient the sub becomes at its lowest frequencies. "pyramids" and RF's are good examples of subs that don't cost a lot, and may work very well in most setups. Not too durable though. I would go for "poly cone & rubber surround" drivers of some type for marine setups, like the Infinity Perfect that I mentioned.

I also personally like the tone of 10's more than 12's. I have 3 JL 12 ohm W0 10's in a sealed, partitioned 1 cubic foot X 3 box and a Pioneer X900 amp running them at a combined 300 watts at 4 ohms. I was using them in my Lebaron until recently (I set it back up all-stock to sell it.) The crossover frequency was set around 55 Hz.

Maybe this summer I will put some audio in my boat.

Ospreyproduction
03-11-2004, 11:55 AM
The Memphis Belle is the most amazing 5 way amp. You can tune the hell out of it, and it's much much more efficient than two seperate amps. We can chat about it all day, but you must go listen. There is a difference.....big difference.

Any Pro audio person will agree.

sho305
03-11-2004, 11:30 PM
I like the 10s best too. Considering all the cars/boats I worked on the best sounding ones had 10s. Systems you would listen to, not compete with. Sounds like a nasty thunder machine there Pyro:) Yes, you would want to address the moisture issue in a boat. I think the paper cones were heavier, and so where tuned lower. Poly subs are better now than they were. I got the Rockfords because I could only use one set, and wanted to push them pretty hard and the cheap ones are only good for so much. Another point is you can blow the cheap ones with 100 watts if you have a poor signal.

I don't doubt that Memphis amp works good, but just how much is it? I have not looked around lately, but I used to not be able to change phase with them/change x-over slope/and some times I like to change out an amp or crossover anyway. If you have the cash and nothing in your closet to use, that would be a nice way to go...less install too. I want to try one for sure.

That Linear Power used to make a 2601 or 2602 amp that had no settings on it. It had about 60w mono for a sub and 35w/channel for highs I think. You could toss it in a car with tens, 6x9s, something in front and it was a no-brainer for a good quick system. Even ran 4 10s on one at 1/2 ohm. Not super powerful, but close to a cheap 300 on the subs. It was not cheap, but that shows how ratings are cheezy. They make some good stuff too at Linear, didn't see that amp on their site. It looks like they have new owners or something, a few years ago I could not find them at all.

I can't find the pic, but the first good sytem I had was in a late '70s T/A. Had that perfect tiny trunk...I had 10s and 6x9s in the back deck, with another set of 10s into the back seat with my two amps rubbing on them. There is a difference between a box in your trunk and having subs aimed right at you in plain sight.

Now you guys have me thinking...I might be able to fit some free air 10s in the bow of my boat:eek: hmm, better go measure it....

Quick Rick
03-12-2004, 07:53 PM
thanks guys, i am starting to get a clearer picture on things now, clear as mud you know. anyway with my two critters, i have to be able to move the sub out of the way so they can crash and i can play. any good ideas to mount it? ex. ski buckles etc. pics would be a groove. i like to double, triple etc. (old motocrosser) so i don.t want this thing smashing thru the bow. thanks guys Rick & no i don,t do it with my kids in.