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Liberator
02-13-2004, 10:07 AM
I am ready to install a stereo into my boat and I have a few questions???
I have a 300promax and dual batteries, How much stereo can I put in without screwing up the electrical system ??

WATERWINGS
02-13-2004, 10:18 AM
I am running two amps with one battery, I just charge up everytime I come in.........1000 watts:eek:

mendo
02-13-2004, 10:18 AM
How many batteries do you want to run?
One of the best set-ups can be found on RV's.
They use multiple batteries and isolate them from the main battery that runs the motor. Most of the parts could be found at the RV store for a system that would let you run the stereo battery (or batteries) until they are dead and then start the boat and go using the main battery. Take a good hard look at the arcticle about the additional alternator from Simon. That would help get them charged up quicker after a day at the beach.

Mendo

Techno
02-14-2004, 12:29 AM
This is just off the top of my head but kind of close.
Most batteries can deliver about 10 amps for 10 hours ~ 100 amps.
10 amps X 12 volts is 120 watts.
If you suck more amps per hour then it won't last as long.
1200 watts isn't available for 1 hour since the battery don't work that way. Some value less than that.

BUT amp wattage isn't consumption. 4 amps in different boats.
50 w, 100w, 500w, and 1000w. Every one of them may be putting out only 50 watts of power. The higher amps are putting cleaner sound out since they are only operating at some fraction of their ability. The 50 watt is cranked up to full power and along with it is the noise the amp produces. The 500 watter is loping along at 1/10 its capacity. The noise is way down there so you can't hear it. So you can put in a huge wattage your just not going to actually use 100% of it but thats the idea behind more wattage than needed.
Simpler- your running the amp at part throttle. You can hear the music over the amps exhaust.

Another item is speakers have differing levels of efficiency.
You can get by with less amps if the speakers are selected carefully.

One thing about multiple batteries is unless they share the load all the time they have to be charged independantly.

As a final mess your head up. Amps are rated at 14 volts not 12. The alternator puts out 14v. The car nuts will also run higher voltages in their special alternators and the amps are bought for this higher voltage.

thaw ripper
02-14-2004, 04:30 AM
NEVER ENOUGH!!!!!:D

sho305
02-24-2004, 10:01 AM
Yes, you get better performance at 14v too. I would think it would be better yet running one of those big caps on a sub amp when you are running off batteries alone.

Just for example, I had a pretty good 300 watt amp running 4 tens at 2 ohms with a good head unit. Maxed out I would blow a 20 amp fuse once in a while. The high/mid amp in this 2 amp system ran 6x9s and small mids and tweeters, and was about 120 watt but high quality. About once a year I blew the 30 amp fuse that only the two amps ran on at the battery. The big one had the 20 at the amp and the other had a 10 that never blew.

So blowing that 20 amp fuse was 14.5v x 20 amps = 290 watts for long enough to blow the fuse. In reality, an alternator should put out 14.5v but it is never spot on due to temp and load. Most amp ratinings are suspect, even good ones don't tell you how much the amp can do with the right setup vs. poor setup.

You can help yourself by running a class C sub amp as most are, they take less power than a quality amp. Try to get speakers and boxes that are more efficient. A ported sub box makes more noise than a sealed box for example. Usually lower rated speakers are more efficient, so try to only run what you need, though it varies. Running the best signal to the amps will get you more out of a smaller amp = less power needed, less noise in the signal.

I like the idea of those portable battery jumpers...they even got a light and power plug too.

GP-1
03-03-2004, 04:49 PM
[You can help yourself by running a class C sub amp as most are






You meant a class "D", right?

sho305
03-04-2004, 09:46 AM
My bad, class D requires less power. Way back when all this stuff became popular I did install at a place. It was amazing what the sales people would sell (product with the best kick back) to customers, instead of what worked better. Did a large system then with 5 amps and it sounded terrible...finally they listened to us and changed out the crossovers after the customer got hot enough. The change was night and day.

You just don't need to spend on the sub side at medium power levels when other things are much more important. I ran a few different 300w amps until I got the one with the right reponse, and ran four 10" pyramids I bought for $20 each back then. Worked fine and never blew at that power with a clean signal. Even using different amps with different headroom would change the performance quite a bit. People were astonished at how well the cheapo subs worked, and I thought come on, this aint rocket science??? You only need enough speaker to hold what you push, and mostly the big power ones work better with big power. I'm not saying expensive subs are not higher quality and better power handling, just that with that power I don't need them.

A great crossover, nearly great head unit, pretty good high/mid amp, good mid/high speakers, and cheaper sub side works nice IMHO. I did some more elaborate systems but not for me; I didn't need to move my hair around any more than 4 10"s would. I liked the sound of 8" better but they can't quite take the power, and I cound not get 8s and 12s to quite work the same but close. Going more complex was just a pain, though you must if you want earbleeding power and sometimes 4 10s don't fit your app. The biggest problem was not being able to try very many different components or find any real stats on how they would work. I have an old blaupunkt 120 amp that works the best compared to 8 other average 300 watt sub amps I tried on 4 10"s, who would of thought?

Funny thing is the best product I ever saw for a system, was a thing called a PAII from linear. It was a preamp with a simple EQ and fader. It would push amps until they overloaded, no not distort, overload and cut out. Wildest thing I ever saw. If I remember it pushed a lot of line level wattage that linear maps liked. It was like a primary volume control for your system; you set the head at 2/3 volume and used this. It could push a pure clean signal until the amp just gave up. Way back then maybe around '90 they were $300 or something, and I never seen anything like it yet though I am not so into that stuff anymore as my stuff still works, and it has become a pretty generic industry now. Oh, and for a while I went through different cars so fast I got too lazy to install all that stuff...just wanted to try them cars out.

I have an old simple high/low Nakamichi crossover. I have plugged it into maybe 10-15 different 2 to 5 amp systems and they sounded better than with the various brands they were using.

GP-1
03-04-2004, 10:20 AM
Wow.... If 4 10's can't supply you with enough power, you've got some serious hearing issues.. I know there's no way I can listen to mine at full volume -- my head will explode. Now, if I could just get my brand-new-from-the-box DOA amp back from Xtant..........

1BadAction
03-05-2004, 07:02 PM
Kewl sho, finally someone that thinks like i do! I have 2 10s in my blazer now, and its WAYYYY plenty to blast the KORN. I do have some experience at this stereo stuff, as shown with this 2000 slamfest trophy...

sho305
03-06-2004, 03:06 PM
Nice trophy:cool: I like 2 10"s, and 4 really rock. It just seems that people see all this major overkill and think they need 5 amps and 30 speakers. Some of the best systems I have heard that went as loud as you would want in the car used 2 10"s, 2 amps, a set of mid and tweeter separates, and a good head/crossover. Larger cars/boats seemed to like a second set of mid/highs to fill more or for rear seating. You can really feel the four tens if you have the room:D . I like the 8" subs, but they seem to puke every time just at the max volume I would like to have on occation.

One of the last systems (sort of a weak system) I put in had fair quality mid/high in front and a round coax in the back. I had no room in the back of this car at all...so I chanced and bought one of those audiovox 8" powered sub tubes. Didn't need a car shaker just nice tunes for driving. It runs signal leads to one speaker and power leads to a source I found in back, has auto on/off. Then I put a good high power deck in and turned the bass down for a little more volume, and let that little sub work the bottom. It sounded surprisingly good. After a year the gain on it shorted, had to resolder it but good yet after 3-4 years now in the third vehicle. Now hooked into a stock ford stereo and really helps that weak thing. They have a higher power one on their site but I can't find anyone who sells them. It was 60-$70, but can only keep up with maybe a good highpower deck or a pretty small amp. I used a trailer plug on it so I can toss it out if I need the room, put velcro on the feet of it and it stays put. Fantastic deal and very easy to improve a weak system. You can move it around to change the sound of it.

So I guess what I mean, is these days you can get $20ea 10" subs and make some good mounting for them. Get a cheap $60-100 amp to run them or used even if you can. Use a smaller better amp on the high side, then spend your cash on a good crossover and head unit. Try to get some nice mid/highs at least for where you sit;) You should have some impressive sound for not that much cash that way. I also find that many coaxs are very bright; the tweeter overpowers. Ok for open space but be careful in a car or it gets too tincan-ish. I've bought some amps real cheap at police auctions here.

Lately I have been experimenting with a 10" DV in a 5th order box, where you have only the port exiting the box. It is smaller than a proper two 10" box but I am not totally sold on it yet. I like the deeper sound, and most boxes premade tend to be to boomy for me and so are big when I make them. This one worked great on a home stereo but I don't have an big amp running to try it on yet. Also have a 8" one made.

Techno
03-06-2004, 05:35 PM
Something I was wondering is if a woofer box could be made from glassed foam? Light and strong but would it provide the non vibration the particle board or MDO does?
Kind of figure those bazooka types don't have the required dampening and seem to work.
Which leads me to wonder if a piece of 10" PVC would provide a simple cheap and light box?
For a new install and proper boat floor config wondered about a floor mount with the space as the speaker box?

I made round tubes from plywood using the kerfing technique. These were just to mount though. Both for the small coaxs in the kick panel and the larger 10" in the doors.
Done right you can seal it and leave the wood look.
An alternative I didn't try was spriraling veneer like cardboard tubes. These can be bought but pretty pricey

For comparision since woofers don't need 2 speakers and to help size choice.
8"=50 sq. in.
10"=78
12"=113
15"=176
Notice 1 -12" speaker is the same as 2 eighters. Circles gain area fast. 2-12s =3-10s

1BadAction
03-07-2004, 08:25 AM
techno- you are going to laugh, but i'll tell ya anyways. In high school my friend wanted a cheap system for his truck. so we bought a TM rush 12" sub, and a 300w Boss amp from a kid for $30. got the wires from walmart and the hookup to go to the factory stereo, for $40. We did the wiring ourselves and got ready to hook the sub up. Oh ****, theres no enclosure. well he suggested lust putting the speaker in there with nothing holding it. After 15 minutes of my laughing at him, i grabbed a 5 gallon PVC bucket. we used double sided tape on the lip to seal it and #6 sheet metal screws right between the edges of the lip to screw it down. i expected it to sound like garbage, but the dam thing sounded as good as a $100 cardboard tube! after awhile i took it apart and stuffed it to get some more volume, but he listened to that thing for almost 2 years. It was still working great when he sold the truck. :D lol what a rig that was.

sho305
03-07-2004, 02:52 PM
I think the idea of using dense materials like particle board is so it will not vibrate or resonate. The round tubes seem to work ok though, and that 8" I have is cardboard too. I keep looking for a project to try one or two of those cheap 10-12" tubes on.

Another point is an empty box will be louder, but the insulation inside will deaden the resonance within, what ever frequency that box resonates at. Usually stuffed it will resonate lower but also less. I try to make odd shaped large enough boxes to cut down on it, and tune it so I can use less or no insulation. I think you could glass up a box, though you might have to have wood where the speaker screws on maybe. Most boats I did we used free air subs, and put them under the seat or something. They worked ok and they didn't want to chop stuff up or lose room. I did a bunch of trucks with a piece of wood behind the seat just far enough out to mount subs on the back side and screwed down under the glass.

bulldogdaddy
03-07-2004, 05:44 PM
you guys seem to now a little about the stereos so tell me what i'll need for this system,seeing i cannot get a call back from main street audio.i gues i should look somewhere else to get it from seeing they don't call back.
but this is what i'm going to install;
1-mbquart nra450 mdl receiver
2- mbquart 6in rounds
2-mbquart 6x9's
1-mbquart10in sub
the 6x9's and sub will be mounted under the deck in the bulkhead and the rounds will be mounted in the sides of the back wrap around.
need any info as has anyone delt with these speakers and unit ,how much of an amp do i need,unit puts out 45w for 4 channels
also has sub output
any info is appreciated

Techno
03-07-2004, 07:23 PM
Why are you using 6x9s?

bulldogdaddy
03-07-2004, 07:53 PM
i thought bigger was better,lol,just that they would fit under the deck

sho305
03-08-2004, 11:25 AM
I've had good luck with 6x9s, they make great fill and usually have a good price. I try to stay away from the ones with lots of tweeter/mids in there, like the ones with four. Not all, but many of those don't have a good mid to low response. I like a good round coax or sperates in the primary listening area. Hard to be pickey in a boat though when it comes to location. Kenwood once made a bigger 7x10 that worked real nice, though I tend to not like K-woods as they are bright. In the open boat they were ok and also were next to the floor...so that cuts the treble. 6x9 help add pure loudness it seems. I can add a set to a separates system and it goes louder, good in a noisy environment. Four amped 6x9s alone will go real loud.

You saying you have no amps and the deck is 45w? Hey, with some thought in wiring, you can try it the way it is and see if you don't need huge volume. Hook up the 45w and get a sub amp that will drive the single 10" well, a mono-capable amp. Try it. If sad then I would try an amp on the high side, a 4 channel if you need to fade front to back. I would get a crossover because then you can cut the bass out of the mids (unless the deck does?), and get better volume out of them that way without a big amp for them; though that makes it harder to fade if you want that. There are also rca level crossovers you can get but not adjustable far as I know. Before the amp crossovers are always the best power-wise, otherwise your amp is still working to make those frequencies you don't want and you can also manage the amp gains/frequencies. I have a sansui amp that will run two channels plus a single sub, but then I nearly need a 5th order box to cross the sub anyway if I use it for mids too. Not very often do subs work well without a crossover. I have an Alpine 35w that works nice on mid/highs with its high quality, even though it is low watt...it is Alpine watts;) Once I even low-bucked a system like that and used a booster on the high side with an amp for the lows. I tuned the booster for a good response and cut the bass out, then I hid the thing. Worked great for a small tunable amp as long as it is good quality and you don't stress it. I'll use whatever works obviously, but that was a small vehicle too.

Watts are hard to judge. I got a blaupunkt 120 that is equal to two different pyramid 300s (and many I know hate blaupunks?)...that Alpine 35 equal to maybe a 75-125watt cheaper amp. Check to see what size fuse they run also, and look for RMS ratings even though they don't tell completely. RMS for 20-20,000 is much different than RMS for 1,000 only. I generaly figure at least twice the wattage needed for a cheap amp than a quality one. You tend to get what you pay for, but since you don't need quality for a sub it is cheaper to get a huge cheap amp in my experience; and then the opposite for the high side. High side being mid/tweet and low being sub. I like to use those foam enclosures on mids also if no box. Sometimes I put a hole in the bottom if too tight.

You really need to approach it considering what you want. Do you want to shake the boat or just good tunes when still, or just make the most of what you have handy? I don't think any deck will do enough for you to hear it well underway, you see how big an amp is and it just don't fit in a deck. What are the ratings on the speakers you have?

Running an average 1-2 sets of tens (maybe one better 10-12") and 2 sets of mid/high speakers; I use about twice the amp on the subs...maybe a cheaper 300 for subs and a better 100 for all else, depending on quality and conditions?. A good crossover/head and I'm gold. Then I swap out or change mouning of the high/mid speakers to get the sound I want if it aint right. I even swap amps as that can change it too. Normally don't have to mess with the sub much if a good mount was used. Sometimes I use caps on the mids to cut them down, or even resistors for some auto fade. I tried 3-5 amps and for all the big hassle it just didn't do more than the good ear splitting I could get from less equipment and some tuning. It was like twins on a boat, you wont go twice as fast:) I love the nasty systems, but would never consider one for normal use. What I do is pick up used stuff when I see it, it is cheap now, or refurbs on the net. Of course, don't get caught with hot stuff. Speakers I tend to buy new more often, they wear out.

I have not used mbquart, but I'll guess that one ten will need all the help it can get in a boat. It might maybe work better running the 6x9s at full range to help the 10 with bottom, I am not sure but you would not want the round mids running bass too. In a noisy place, your bass is the first to go away so you can't have too much sub IMO within reason. Just that the darn things are heavy. That is why I wondered if anyone had used those tubes in a boat, they are pretty light. Jeez, I gotta shut up here...:rolleyes:

bulldogdaddy
03-08-2004, 12:43 PM
you always help out alot!
heres a link to the webpage,look up mbquart
http://mainstreet-audio.com/marine.htm?source=overture

sho305
03-08-2004, 04:00 PM
Not cheap stuff, they look like they should work fine. Time for amp shopping:) How you going to mount the sub/does it need a box? Some can run free air and some can't.

You might be able to get a do-all like this: http://www.mainstreet-audio.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=1&Product_Code=45066

Hook it all to one amp with a crossover/etc and be done with it.

Techno
03-08-2004, 05:13 PM
You lost me on the free air woofs. I though this meant a very large enclosure like a car trunk or boats under floor, still an enclosure.
For the comment on deck amps and amp onlys I think they lie on the head units or just max them out into unusable output readings.

The old rockford amps I bought are very low rated but if figured in a system put out 640 watts. If I remember 2-25s and a 35. Thats only 85 watts but it isn't:confused:

sho305
03-08-2004, 08:56 PM
There are some that are not to be used free air, they tend to have lighter cones and less dampening. They are more efficient though. Others handle more wattage in a box and some don't care. I'd guess most HD ones don't need a sealed/ported box. A ported box will make more noise, or the most noise really if tuned to the sound you like.

I remember seeing old rockord punch 45 and 75 watt amps. The 75 would rock pretty good, not a toy. 45 not bad either, I think they had a bass gain on them if I remember right and were not real big. They were pretty good stuff.

I never got an amp with the crossover stuff in it, though I want to see if it would work ok. I'm sure you can still use it without the features anyway.

sho305
03-08-2004, 09:22 PM
I think this is the bad boy: http://www.linearpower.com/html/index2.html

Note the listed $379! But then they say you get a break if you order. This thing is just plain unreal, I found others too they are line drivers.

Made in the USA, used to put these amps in all the time many years ago. They were indestructable power houses. Used to use these old Pyle 10" that had magnets near as big as the speaker and you could not kill them. You could run bare speaker wires from a deck into the RCAs on these amps and run them just fine...in fact you got less noise that way in some cases running 5v. People would freak out when they saw that. Real high quality stuff!

paul folks
04-15-2004, 09:10 PM
i have 12 12's w/ 30k watts in my van but it still isnt enough

Techno
04-15-2004, 09:27 PM
Get in the van and it'll be enough.
Standing outside don't count;)

2fast4mom
06-03-2004, 10:17 AM
1,380 watts in my Allison, by means of 2 Rockford-Fosgate amps, 700w bridged amp for the sub and a 4-channel active crossover amp for the other 8 speakers.

I run a single Optima blue top, same as the cranking battery, I have never been stranded at a beach yet.

The earlier discussion about clean power, operation percentages, and noise amplification is correct. You won't have any trouble with the charging current that 300 motor produces.

sho305
06-03-2004, 10:45 AM
I was not clear on the free-air woofers if anyone cares. Some have larger magnets and more internal damping to be able to run without an enclosure. Usually you can't run as much max power as the air in a box helps damp the speaker. You only need a baffle; you need to mount them in a panel that separates front from back like under a seat where the seat platform is not sealed.

The ultra hi power sytems never use these as they are looking for max noise, but they work fine for a moderate system you are just listening to where it would be nice to mount without a box. These you would run in a rear deck of a car with them open to the trunk for example. I put in lots of say 200-300 watt amps running a set of 10" subs in cars that sounded real nice and thumped without blowing your head off, used them with say 6x9s and mid/highs in front. If you are going all out they will not work. Of course in a car then you didn't need that huge box in the back either. With newer cars that have little or no deck, hatches, folding seats, etc, you can't do that.

I heard a few mounted open into a big port that came inside the car, but many of those didn't work well only a few did. It worked better to seal a board to the smaller area and then just mount them on that with as much of the sub aimed out the smaller opening as you could get.

On the other hand, you may be better off using less subs in a good enclosure that takes up less room and forcing more power to it...that could be lighter overall depending on your situation. We didn't care about weight in cars and the big boats I mostly worked on.

TNT
06-03-2004, 10:47 AM
if you email me id be glad to help u out i used to sell stereo for cars and such at a local best buy and i think ill be able to help you out my email is heisheich0052@aol.com