Speaker & Sub Selection & Placement
 

Hey all. New to OSO & new to boat ownership. I've recently purchased a 1993 Baja 240 Islander that has been very well taken care of by it's previous owner (look for Penny Dropper in the Baja section). I live in Las Vegas, having moved here for work about a year ago from Washington State (man I love the desert life and weather!!). Lake Mead is right here and Lake Mojave is just down the road, but I will probably spend more time on Lake Havasu as I have a good friend with a home there and plan to get down a half dozen or so times this summer with the next trip being for Desert Storm weekend at the end of April.

Part of having fun on the water is having a good stereo, something this boat is lacking. It came with an older Sony head unit and 2 pair of old Pioneer 6x9's, a pair below the back bench and a pair under the dash on either side of the boat. I've spent HOURS this week reading and taking as many notes as I can to try and put together a system. My goals with the system are; 1. economic 2. balanced 3. clear and 4. efficient.

I plan to keep the old Sony head unit at this point. It works, and has a nice remote control on the drivers dash that allows me to control volume/mute the music as necessary. At this time, the only means of music I have is the FM radio (no cd's and I don't do mp3's), and honestly I quite enjoy Jack FM River Rat radio so I don't really think I need to upgrade except for maybe the case that the pre-amp outputs are a lower voltage than desired? (I need to find out what they are) I am going to add a Clarion EQS746 EQ which will allow me to use an Ipod or phone with the proper adapter to RCA jacks as my auxiliary input, with the headunit being the primary input into the EQ. The EQ has a main volume control, a front & back fader, and a sub volume control, along with all of the frequency adjustments that I have no clue how to properly adjust.

I plan to have 2 separate zones which will be controlled with the front/rear fader control. The main cabin speakers will be the front. I'll utilize a y-splitter off of the EQ front output to feed what will most likely be the 2 amp channels that power the cabin speakers. The rear speakers will be speakers that will be modular. I think I will have a set of 6x9's in some cheap wake tower enclosures that will be kept either in the engine compartment or maybe tucked in the the sides towards the rear of the gunwale storage area on each side. They'll have long wires that will allow me to pull the speakers back and hang them off the rear rail above the swim deck for some sounds when we're floating around in the water. I may put another set of speakers up in the open bow on the rear channel, but at this time there isn't really a place to put them unless I build some type of enclosure and that will be a project for a later date.

While I have the skills and tools to do the all of the install myself, I really lack current knowledge of today's stereo equipment. There are just too many options to choose from and I'm terrible at making a decision. I hope that you guys can help me make a decision and I can get stuff ordered so I can get everything installed and buttoned up to enjoy at Desert Storm.

My first request is cabin speaker placement and selection. In all the reading I've done, getting the speakers up high results in the best sound quality. Along those lines, the location of stock 6x9's (way down low) will not work and i'll probably be cutting some new holes in the gunwales which I'm fine with as long as I feel confident that the placement will be the best possible. I am thinking 2 sets of speakers in the gunwales and possibly a set of horn tweeters up on the dash. I've read where these horn tweeters really help complete the system at a very economic price level. I will probably play around with the location before either cutting a hole in the gunwale to point them inwards towards the boat, cutting holes in either side of the dash and pointing them back towards the stern, or building some enclosures that allow me to point them towards the center of the main cabin.

I'm thinking the cabin speakers go here? Any input?

https://lh3.googleusercontent.com/FO...=w1159-h895-no

https://lh3.googleusercontent.com/8m...=w1159-h895-no

Looking at speakers and assuming the front channel will have the 3 speakers and one set of horn tweeters, I have put together 4 sets of speaker options that I would like input on. I am not dead set on the 4 sets. If you all think the two sets in the gunwales are suffficient, I'll keep the money in my pocket! I've never been in a boat with any type of system, so I just don't have a baseline to help me make a decision.

Cabin Speakers Target budget $300.00

Polk db651 Front Gunwale $65.00
db691 Rear Gunwale $95.00
db651 "kick panel"? $65.00
Horn Tweeter Dash? $30.00
$255.00 total

db APS6.0W Front Gunwale $58.00
Drive APS8.0W Rear Gunwale $91.00
APS8.0W "kick panel"? $91.00
Horn Tweeter Dash? $30.00
$270.00 total

Boss MR652c Front Gunwale $45.00
MR752c Rear Gunwale $67.00
MR752c "kick panel"? $67.00
Horn Tweeter Dash? $30.00
$209.00 total

FusionMS-FR7021 Front Gunwale $118.00
MS-FR7021 Rear Gunwale $118.00
MS-FR7021 "kick panel"? $118.00
Horn Tweeter Dash? $30.00
$384.00 total

With any of the 4 above options, I'll be looking at a 4 channel amp capable of at least 150wx4 @ 2 ohms, assuming that he speakers will be paired up and wired in parallel to create 2 ohm loads. I've got my eye on 3 different very similar amps. I've selected class d full range amps as I've read that these are much more efficient than the class a/b offerings.
NVX JAD800.4 Full range Class D 125x4 - 4ohm 200x4 - 2ohm $200
PPI P900.4 Full range Class D 145x4 - 4ohm 225x4 - 2ohm $170
Polk PA D4000.4 Class D 125x4 - 4ohm 200x4 - 2ohm $230


You can see where I am at budget wise, so if you know of something that is of much better quality around the same price, I am open to suggestions and appreciate all input.

Subs

Unfortunately when the previous owner recently put a new floor and carpet in the boat, they did not rebuild the rear bench seat. It was constructed of painted plywood and then covered in vinyl. It has been deteriorating and leaving wood splinters all over the floor, so I've torn it out and am in the planning phases of the rebuild.

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My initial thought was that this was the perfect opportunity and location to install a couple of sealed down firing subs, one on either side which would still allow for my storage area under the center of the bench. The design and fabrication of the boxes would be straighforward and simple because they would be rectangular, and the location is very secure and would not be an easy target for thieves. In my research, it is clear that the most ideal location for a sub(s) is mid cabin under the dash as space allows, so the rear bench will be rebuilt with nothing but a storage compartment (unless someone can talk me into something different). If there is no space under the dash, then in the sides under the gunwales seems to be the next best option as SPL2k did here (very clean install!!). Fortunately for me, I could pretty comfortably curl up and sleep under the dash on either side, so there is LOTS of room for a single or multiple enclosures (one on each side?).

Like speakers, there are just too many options. Again, not having been in a boat with a system before, I don't have a baseline for what things sound like. Will I be happy with one 10"? One 12? Will I need 2 12's to give me the balance I desire. I don't need the loudest pounding system, but I want the bass to sound well balanced with some room to crank it up if I do want to wake the dead. From what I remember when I was in high school, if you over design your subs and amps and can run at a lower volume/gain, the bass sounds much better (at least to my ears). I'd like the sub(s) to respond well to all types of music, from the latest obnoxious summer mix filled with bass that someone wants to play, to the 70's and 80's rock that will come in through on the FM radio.

I am thinking to allow myself the opportunity to expand and keep the initial costs down a little bit, I should target subs with dual 4 ohm voice coils. With a single sub, I can wire the voice coils in parallel to give me a 2 ohm. If I decide that the bass isn't enough, then I add another 4ohm DVC sub and wire the two subs in parallel for a 1 ohm load.

Here are a couple subs I am looking at. Open to suggestions here, these subs have very good reviews and reported outputs for their cost and in a sealed enclosure, space requirements are very reasonable.


Dayton RSS265HO-44 10" 600wRMS 1200wMax 4ohm DVC 90.5db 25hz 600hz $140 0.55 cu ft sealed volume, 46hz F3 (i don't know what F3 means)
Dayton RSS315HO-44 12" 700wRMS 1400wMax 4ohm DVC 84.6db 20hz 500hz $157 0.49 cu ft sealed volume, 47hz F3
NVX VCW104 10" 750wRMS 1500wMax 4ohm DVC 83db 20hz 200hz $150 0.70 cu ft sealed enclosure

Can anyone comment on the difference between the higher end of the freqency range? The Dayton's go much higher, is that a good thing, bad thing or does it not make any difference?

I could probably find some cheaper subs, or some higher quality subs at a good price on Ebay. There are so many options, I just don't know what to look for. Kicker? Rockford? Polk?

To power the sub (s), I am looking at the same lines of amps in class D monoblock. They are all 1 ohm stable, so they work with my idea of system expansion if I need another sub.

NVX JAD1200.1 Class D Monoblock 500x1 - 4ohm 800x1 - 2ohm 1200x1 - 1ohm $230
PPI P1000.1 Class D Monoblock 580x1 - 4ohm 725x1 - 2 ohm 1000x1 - 1ohm $160
Polk PA D1000.1 Class D 500x1 - 4ohm 800x1 - 2ohm 1200x1 - 1ohm $225


Again, open to suggestions if they are in line with the costs of the components above and appreciate all suggestions!

For sub installation, I am going to start on the port side first. I am thinking a small box built to fit the contour of the side of the boat in the front of the dash area.

https://lh3.googleusercontent.com/RF...=w1194-h895-no

Which direction should the sub face?

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Any pointers on box construction that I should keep in mind? Obviously I'll make sure there is clearance for the travel of the sub regardless of it's orientation.

If I did want to go with two subs right off the bat, am I better off making a separate enclosure for each side, or will putting two subs on the port side yield the same results? It sure would be easier to keep them on the same side.....

You have done your homework. The alpine type e is cheap durable, and 2 10s in the bench lower wont take much space or power using the bench as a enclosure. (Properly sealed all around) some models of the old pioneer 6x9 coax.layed down some midbass. Most contemporary 6x9s do best with some volume behind them, and will thus allow you to to switch back to class ab amps without a huge hit it listening time.
unless dr Bose is your brother in law trying to create a impressive 80's rock sound with todays sub $200 class d amp offerings wont be easy. Crawl back in the baja and see what can be done (if anything) to put some enclosure behind speaker locations it has already. The more volume the better. Explore some dayton or scanspeaks 6.5s if yourwanting to run horns . Remember 6x9s and drivers meant for doors are maximized for near free air configuration

I would buy used kicker or fosgate amps and run a 4 ohms before i bought new amps and ran cabin speakers at 2 ohms if i wanted to stay at a certain budget..

Any certain line of either amp you would stay away from? I know Fosgate has like 3 different series of amps....

Why not run at 2 ohms?

Space is not a concern. In the bench is easy and each sub would have it's own sealed enclosure, but if putting them mid-boat under dash is going to give much better performance that's what I'll do. I've read on another forum that mid-cabin is 10x better than under the bench , a post which was made by a professional installer in Havasu. I trust his word, just looking to hear real-world experience of others.

Can you explain this a bit more. With higher volume, the class a/b becomes as efficient as a class d? That is how I read that, not sure if I understood though....


There is a TON of space behind where I am proposing to install these speakers in the sides of the boat. I was thinking I could buy some baffles for the backs to try and direct all of the sound out into the boat, and not back into the gunnels. But, a lot of reviews of these types of baffles on amazon report decreased performance because as you say, most of these speakers are designed to be free-air....

Thanks for taking the time to comment and give your opinion!

Baffles for cabin speakers you just want to seal the front from the back airspace wise.make sure the engine room can still get airflow though.
Most benches esp. The oem fiberglass bench seat bottoms are not even remotely sealed and solid enough to satisfy the purist audiophile stereo shop owner. But since you have to make a new one anyway, 2 cheap type e's or daytons running off even a jbl 300.1 wont sound bad especially if you get the cockpit speakers sealed somehow. Thats the biggest pita in a boat like that.

I would go a little bit of a different direction and keep it simple. First I would ditch the current deck, and pick up a new marine one. Even a cheap Clarion deck will do everything you need. You can still split it into two zones with the wiring. It will give you a CD player, AUX input for a iPhone, and you will get all the preamps you need for subs and amps. They are also the same price as the clarion equalizer. From there you can run any amp to run the speakers, and depending on how many you want, you may not even need one. What I did was I got a kicker sub and built a custom box to go under the rear bench. Something like this would probably be fine for a boat your size, and even though it is not a marine sub it is fully water proof. http://www.crutchfield.com/p_2061CVR...02.html?tp=111 . Pair that with an amp like this http://www.crutchfield.com/p_236WET5....html?tp=61752 and you would be good to go. This would still come in at a descent price point, and they are well known companies. I have kicker speakers as well in my boat and they have been great. Sure they are not $400 a pair JL speakers, but they have worked perfectly for 5 years with no issues. One thing to look for is the deck. Certain ones you can easily add wired remotes, and others can be controlled through bluetooth. I have a wired remote at the helm and another on the swim platform which is nice. Obviously those are bit more expensive but probably worth it. As you can see I like crutchfield.com as their prices are good and their customer service is great.

Not sure if you're already finished your install but I appreciate all the thought you've put into things. Here are a few suggestions or maybe just some food for thought:

1. Where do you expect to use your stereo most of the time? For me, the answer is about 80% of the time while I'm rafted up floating behind the boat. It's hot here in Oklahoma and we spend much of the time on the lake in the water.
If you are the same, I would set your stereo up for that purpose. For me, this involves installing a new head unit. A Sony MEX-XB100BT. It has bluetooth connectivity and has a smartphone app called SongPal that lets you control all functions of the head unit. Full control of the audio system without having to get up into the boat or go to the transom to a wired remote is ideal for me.

2. Cabin speakers do not need to be loud for most people. I honestly never listen to music while in the cab of my boat unless riding out some rain or something.

3. Instead of modular speakers, why not put speakers right in the transom? Unless you want the sound to be directed out the sides of the boat, these will work better than bulky modular speakers that you have to store somewhere and have to setup every time you want to raft up. Not to mention idiots that will inevitably grab ahold of one of your modular speakers to climb onto your boat and break the mount. Mounting in the transom is much cleaner.

So this is what I'm doing in my boat (Scarab 29)

Sony MEX-XB100BT - Full control from anywhere via phone app.
Soundstream TN5.950D - 5 channel class D powering the whole setup. (I'd recommend a class D in marine environment. Much more efficient than class A/B and the audio quality is of no concern on a boat.
Cabin speakers hooked up to Sony MEX-XB100BT front channels at 40 rms x 2
DC Gold 4" coaxials in dash and Clarion 6.5" coaxials under rear bench wired together for 2 ohm stereo to front channels of Soundstream TN5.950D at 65 rms per speaker
Four DC Gold 4" coaxials in transom of boat above swim platform wired together for 2 ohm stereo to rear channels of Soundstream TN5.950D at 65 rms per speaker
Two Sony Xplod 10" subs in .75 sealed enclosures under rear bench wired together for 2 ohm mono to sub channel of Soundstream TN5.950D at 215 rms per sub (These came with the boat, May change out the subs if they sound like garbage).

With the above setup, I'll fade it forward to listen to music in the cockpit/cabin and fade it to the rear to listen from the transom speakers and fade it middle to listen to all at the same time. Will have control over everything from Android phone with waterproof/floating case.

I appreciate all the input. Jstrahn, your advice is sound, and I wish it'd have come earlier because you made some great points.

I have purchased everything for my system and am beginning on installation this weekend.

As planned, I am keeping the current head unit. I purchased the clarion EQ, which gives me the pre-outs I need (F, R, and sub) and they are 6v pre-outs compared to the 2volt pro-outs on most of the cheap head units. I purchased an exile audio 4.0 blue tooth unit to use as the auxiliary input into the EQ which will allow anyone on the boat to pair their device as opposed to worrying about having the proper cords to connect different phones. I don't have any digital music other than using pandora so I will rely on friends for the music.

It took me a month to decide on the speakers and amps, I'm terrible at making decisions when there are so many options. In the end I decided on Powerbass coaxials mostly because of price and looks honestly. They have a new marine line out with an 8" coax, the XL-82ss and I picked up a pair of those off eBay for $110. These will go in the gunnels adjacent to the rear bench seat. I also picked up a pair each of the 3xl 6.5" and 5.25" coaxs on eBay and will select a pair to go in the gunnels up by the dash on either side. How the speakers fit with existing holes and my new Dana marine side mount control will determine which size I end up installing.

For subs, I ended up finding a pair of Kicker compVR DVC 12's on Crutchfield scratch and dent for $175 shipped. They will be wired up for a 1 ohm load. I contemplated going with Powerbass subs, but their lower end subs have a paper cone and foam surround, and I decided I didn't want to risk getting them wet and ruining them. The next model up was another $50 more expensive than the kickers so I went kicker. The kickers are a poly cone with rubber surround.

The subs will be mounted one on either side under the dash in the locations shown on my pictures above. They will face each other, ie subs pointing towards each other, not back towards the passenger.

I went a little overboard on the amps, I got a PPI phantom 900.4 for the coaxs, and a PPI phantom 1000.1 for the subs. They're both class D amps with the 900.4 being a full range and the 1000.1 a mono. I ended up paying $380 for the pair with 3 year warranties from sonic electronics. I kind of regret not just going with a 900.5 like many do, just because I would have saved $200 and probably would have been just as happy. At 12v, the amps I bought end up putting out just above the RMS wattage of my speakers so I figure they give me room to grow my system if I decide to add another couple pair of speakers down the road by wiring everything in parallel at 2 ohms.

Your comment about how I listen to music is a great one and one I don't really have an answer for because this is my first boat and I've only had it on the water once. I suspect I'll probably be adding some speakers just above the swim deck like you are for next season, which my amp will allow me to do no problem going to 2-ohm on each of the 4 channels.

Sounds like you're going to have an awesome setup. Would love to see pictures once you complete the install.

As for the larger amps, head room is your friend. I'd much rather have power to spare than be underpowered. Most blown speakers occur because of people overdriving underpowered setups to clipping. Rarely will speakers fail due to overpowering.

I may be underpowered with my plan to use a single Soundstream 5 channel. We'll see once I get it installed.

How about some follow up. Nothing makes any noise yet, but I'm getting closer.

The goods:

https://lh3.googleusercontent.com/uU...q=w673-h898-no

The hardest part. It took me 1 jigsaw blade per speaker hole to cut these bastards out. These were Home Depot Bosch brand blades and they were the fine tooth models. Not sure why, but the teeth were gone after essentially a quarter of the circumference and I basically burned the rest of the hole out!


https://lh3.googleusercontent.com/Q4...=w1196-h897-no

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This past weekend was continuation of the stereo install. First off, I built some brackets to install my equailizer. I found the perfect spot for it, out of the way yet easily accessible.

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Next up was building the sub boxes. I ended up with a sealed volume of 1.35 ft3. The manufacturer recomended 1ft3 for a compact sealed enclosure and with the space I had and the area I wanted to fill with these boxes, that's where I ended up. It is essnetially a rectangular cube, taller than it is wide, and the sides are designed to follow the contour of the side of the boat. There is a little pocket between the rear wall and the side of the boat that will be used for storage of small, very seldom used items - safety gear like first aid kit, flares, extra sunscreen, portable battery backup/jump start pack, etc. I mocked the box up in cardboard first and then drew out all the panels in CAD. Turned out OK for my first real carpentry project.

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I used t-nuts for securing the woofers to the face and I did disassemble everything and glue all of the seams using some Loctite 375 construction adhesive. I purchased some speaker connectors from Amazon that had good reviews and installed in the top of the boxes to keep the rear storage area free of wires.

https://lh3.googleusercontent.com/xR...g=w712-h950-no

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The final project for the weekend was building the amp rack. The best place I could come up with was on the front bulkhead under the helm. I build a plywood mounting plate and pre-drilled the mounting holes for the amps and installed t-nuts onto the back. I then pre-drilled and laid out the mounting holes with t-nuts for securing the wood to the bulkhead. The little piece on the lower right side is where my distribution/fuse block will be mounted for my ground & power leads. At this time, everything is going to stay bare. I just have too much ahead of me to get this thing onto the water for the 28th. I still have to run all the wires for the stereo & speakers, finish the fabrication and install of my rear bench which isn't going to get covered either (only polyurethane treatment at this point in time), install my new starter which is on it's way, install my new batteries for the stereo, associated battery wiring and switch installation, and then re-install the rear hatch. I've got a busy weekend coming up!

t-nuts for mounting to bulkhead

https://lh3.googleusercontent.com/Dn...e=w712-h950-no

t-nuts for mounting amps

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crappy low light iphone pic of install

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That's all for now!

Very nice job. Good idea with the cardboard for mock-up. Bet it sounds great.

So some feedback after having the boat on the water for a weekend.

I am thrilled with the system. The bass level is perfect. It gets as loud as I want, and hits hard and tight. I am slightly disappointed in the highs, and I'm not sure if it is because of the speakers, the amp settings, the equalizer settings or the fact that they are in an large open environment and I just need more tweeters or horns. I am going to do some research and come up with a game plan, but will probably start with some tweeters in pods up under the windshield pointed back into the passenger area. I am also going to build some baffles for behind the speakers to help direct more sound out into the passenger area as opposed to bouncing around back in the gunnels.

I don't have any pictures of the final install, but here are some additional details.

I ended up adding two group 31 Napa Marine Deep cells (part # 8231) as stand alone stereo batteries, ie, they are not connected to the alternator or any other accessories. I have two group 24 interstates on a dual battery switch for the engine, so I don't need these two batteries for any other purpose other than the stereo. The batteries are charged nightly on shore or at the marina using this dual bank battery charger plugged into a 120v source (http://www.amazon.com/NOCO-GEN2-Wate...ilpage_o02_s00).

The two new batteries are wired in parallel. I used a blue sea fuse block terminal (http://www.amazon.com/Blue-Sea-Syste...ilpage_o04_s00) with a 200 amp fuse (http://www.amazon.com/Blue-Sea-Syste...ilpage_o04_s00) connected right to the positive bolt to protect the positive 1/0 gauge welding wire running to the power distribution block at the amplifiers. I also ran 1/0 gauge welding wire for the ground to the distribution block. The distribution block is this unit, and works great for a 2 amplifier system (http://www.amazon.com/KnuKonceptz-KN...ilpage_o05_s00). It's compact and you can use it for both your power and ground distribution. I ran 2-gauge welding wire from the distribution block to the amps for both power and ground.

I ran a power wire from the battery to a switch on my dash that turns on all items in my system - cd player/radio/headunit, remote wire to clarion equalizer, blue tooth receiver, and remote wires to amplifiers. The load wire from the stereo switch is ran to a k4 2 circuit tab style terminal block which looks like this (http://www.k4switches.com/electrical...terminals.html), just with 2 circuits instead of 6. One circuit is the power circuit for all of the items listed above, and the other is the ground circuit with a single ground ran back to the battery.

I just spent the weekend on the lake and was able to listen all day - 6am to 4pm - as loud as I wanted and I'm sure it still had a few more hours left in it. I can't see needing any more stereo than I have, except for the highs or some additional mids on the transom or in the bow depending on my usage throughout the summer.

One thing to keep in mind is that as frequencies increase, they become much more directional. With subwoofer frequencies below around 80hz, they're non-directional but once you start approaching midrange and high frequencies, being off-axis will seriously impact volume and clarity.

You might take a look at where you are sitting when listening to the system and place speakers accordingly.

For this reason, I've chosen to mount a speaker in my dash and one in front of the passenger bolster firing directly at the front seats. These will be wired to the front channels of my amp so I can fade it to front when underway in the boat. Having the speakers firing from the side of the boat, as most installs on boats do, you lose a lot of sound.

Then I'll have speakers in the transom of the boat on the rear channels and can fade back to those when in the water behind the boat. That way the speakers are firing directly at the listener. To me, it makes a lot more sense than just throwing dozens of speakers placed in the sides of the boat and boatloads of power at them so that you can get loud enough to overcome being way off-axis.