Need help building marine speaker boxes??

AngelC

Petty Officer 2nd Class
Joined
May 28, 2008
Messages
189
Hey fellows,

Has anyone or does anyone know what material I can use to build two separate speaker boxes for 10"inch speakers. I can't use particle wood beacuse it would soak up the water and eventually fall apart. The boxes are only going to be about 14"inches wide by 8"inches high and about 8" inches deep.


Thanks,
 

devnull

Recruit
Joined
Jan 8, 2009
Messages
2
Re: Need help building marine speaker boxes??

How about a marine grade plywood and marine carpet covering?

Basically build them like the floor in a boat would be constructed.
 

AngelC

Petty Officer 2nd Class
Joined
May 28, 2008
Messages
189
Re: Need help building marine speaker boxes??

Devnull,

Where would I be able to get marine plywood and carpet? Also would that would effect the sound of the speakers, I know that particle wood is mainly what is used because it helps the speakers get their full sound and not so empty of hollow. Have you used the marine plywood for any speakers?
 

NSBCraig

Lieutenant Commander
Joined
Aug 21, 2007
Messages
1,907
Re: Need help building marine speaker boxes??

Are you sure particle board isn't just used cause it's cheap.

On profession speaker cabinets they always use expensive ply, never particle.

Thats kind of the big give away if it's low grade junk or not.

I'd just use some cabinet grade ply from home depot etc and glass it so it's sealed.
 

a70eliminator

Captain
Joined
Sep 9, 2007
Messages
3,688
Re: Need help building marine speaker boxes??

I made a set of enclosures from a round carboard tube, the tubes they use for concrete forming (lamp post bases) you have to paint them with resin to make waterproof.
 

fishrdan

Admiral
Joined
Jan 25, 2008
Messages
6,989
Re: Need help building marine speaker boxes??

MDF (not particle board) is preferred because it has good qualities for a speaker enclosure, solid through out, uniform density, good dampening, etc. I'm sure the same holds true for expensive plywood since it has no voids and a high number of plys. Both can be used, though MDF will swell up like a puffer fish if water gets on it. But yeah, particle board is junk for building a speaker enclosure.

If it were mine I'd use Arauco plywood (lowes) and then seal the carp out of the exterior and edges to make sure everything is sealed 100%, including all screw holes. Cheap, but still a good quality plywood.

I like A70's idea also, though I have never tried those cardboard form tubes. Could cause some funky resonance or ringing since the cardboard is so hard.
 

Utahboatnut

Senior Chief Petty Officer
Joined
Jan 15, 2009
Messages
785
Re: Need help building marine speaker boxes??

I would think you could use the fiberboard and once you are finished with construction paint with good oil paint or seal them with some thinned resin, then carpet or whatever you were going to finish with. I agree that they could swell if un treated but if they were sealed up well would work fine. How much water are you going to be getting on them? Use the quick connectors and remove for winter or layup and you should be fine. Some of that plywood is way expensive just for a carpeted speaker box. Put some of those little rubber feet on the bottom corners so air can move around it.
 

rtpassini

Chief Petty Officer
Joined
Nov 27, 2008
Messages
508
Re: Need help building marine speaker boxes??

subwoofer enclosures are either made out of mdf or fiberglass.
same with "external" speaker boxes.
 

cpubud

Chief Petty Officer
Joined
Jun 18, 2008
Messages
468
Re: Need help building marine speaker boxes??

you could use anything you want as long as you seal it with fiberglass resin.
 

mthieme

Captain
Joined
Oct 6, 2007
Messages
3,270
Re: Need help building marine speaker boxes??

I agree that MDF is going to give best sound quality.
I also agree that MDF and water don't mix.
My first thought of a comprimise was a thick plastic - Corian perhaps, or even fiberglass. For that matter fiberglass over the MDF.
You could also use a solid wood which is dense and more water resistant than MDF - Mahogany, Teak (how deep is you pocket?), perhaps even red oak.
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Need help building marine speaker boxes??

Ever think about the newer composite (plastic) wood, being sold for decks?

Easy to work with, gray in color, can be screwed together, definitely weatherproof....

http://plasticlumberyard.com/
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Need help building marine speaker boxes??

From my speaker building obsession days, MDF is the prefered material for most full freq range speakers. For subs, where the wavelengths are longer than any of the box dimensions, shear stiffness of the panel is more important. ie void free plywood is better. A well built home sub would have two layers of 3/4" plywood, or 3/4" plywood ext with mdf on the inside. Weighs a ton, and you don't move them very often.

Now, back to reality of the boat, where audiophile acceptable sound will never be achieved: a good compromize of weight vs stiffness, would be to use 5/8 ext plywood, with some internal bracing. Seal the boxes on the inside and outside to prevent moisture penitration. MDF would be extremely hard to seal, and keep sealed, on the ends. It is also heavier than the same thickness plywood. Lightly fill box with Acousta Stuff.

I have made sonotube subs and speaker enclosures, but different mfg of the tubes have different coatings. The unsealed ones would have the same problem as MDF to keep them sealed.


http://madisound.com/

http://www.parts-express.com/
 

NSBCraig

Lieutenant Commander
Joined
Aug 21, 2007
Messages
1,907
Re: Need help building marine speaker boxes??

Hey I totally disagree with MDF giving the best sound quality.

I don't know of any pro speaker cabinets made of MDF.

From critical listening studio monitors to PA to guitar/ bass cabinets none are MDF.

You only find that in consumer goods.
 

rtpassini

Chief Petty Officer
Joined
Nov 27, 2008
Messages
508
Re: Need help building marine speaker boxes??

My brother has JBL pro speakers and subwoofers.

this is what they are made of.
Dense material such as void-free "marine-grade" plywood, Finnish or Baltic birch type, 19 mm (3/4 inch) or even
thicker plywood is recommended where enclosures will be transported frequently, while high-density fiber or
particle board (not chip board) can be used for permanently installed use.
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Need help building marine speaker boxes??

Pro and guitar speakers are not designed for critical listening. They are designed to handle the harsh environment. Hense, why they are mainly made from plywood.
 

NSBCraig

Lieutenant Commander
Joined
Aug 21, 2007
Messages
1,907
Re: Need help building marine speaker boxes??

Pro guitar cabinets start with good ply and then go on to solid poplar. That's the difference between a $400 cabinet and a $1.000 not the speakers but the wood. Cheap semi pro stuff is particle board and cheap ply.

Why pay so much when a cheap-o with the same speakers costs only a couple hundred- sound quality.

Likewise with pro PA speakers and yes modern linear array's are designed for the quality of sound. Being able to handle the road is beyond being a given, it's all about quality.

Which JBL's?
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Need help building marine speaker boxes??

Pro, concert, and instrument speakers are built to different design goals. I am not sure how else to say that. I suggest you search the net on "speaker building MDF" and you will find allot of info, including what I pasted in below. Sealed plywood is the way to go in the boat. Any grained wood will have expansion/contraction problems with the high humidity and temperature swings.

Q: Can I build speakers with {MDF | particle board | plywood | solid wood}?
A: You can build speakers with whatever you like ! However, MDF is often the material of choice. Its stiffness and density yield good accoustical damping properties. Particle board and plywood are cheaper and can still be used if cost is an issue. Plywood (especially if void free) can be used in the main baffle as a sandwich material to better hold fasteners. Plywood is also a good material for making braces inside speaker boxes. Solid wood (lumber) suffers from movement - the swelling and shrinking of wood due to environmental changes such as humidity - and is therefore not a good material for speaker enclosures. Lumber is also not as acoustically dead as MDF.

There are times however, when plywood, particle board and other common sheet goods are more than suitable for enclosures. Such possible uses include sound reinforcement, musical instrument cabinets, and PA systems.
 

NSBCraig

Lieutenant Commander
Joined
Aug 21, 2007
Messages
1,907
Re: Need help building marine speaker boxes??

Your absolutely right no type of pro equipment is designed like consumer stuff.
Pro studio monitors the stuff the music your listening to was recorded/mixed/mastered on are made of solid wood.

Semi-pro ones like the Alesis Monitor one MK2's I'm listening to are made of MDF the is specially built and ordered by the company just for that purpose(not what you get at Home Depot).

Either way you will never design a speaker cabinet that even remotely works or sounds even close to the quality of either one of the above.

You can make a speaker cabinet out of anything.

All your doing is taking a big guess on how they will work with the speakers you buy anyway.

I think we all are kind of in the same place on what to build them out of (although I think since your glassing it you'd be fine with 1/2" ply, it would be better then most of the speaker enclosures people have made for a car, but still try to go a better dense grade).

Don't really want to bog the thread down with it but- MDF doesn't sound best. Don't know how else to put it.
 

rtpassini

Chief Petty Officer
Joined
Nov 27, 2008
Messages
508
Re: Need help building marine speaker boxes??

Pro guitar cabinets start with good ply and then go on to solid poplar. That's the difference between a $400 cabinet and a $1.000 not the speakers but the wood. Cheap semi pro stuff is particle board and cheap ply.

Why pay so much when a cheap-o with the same speakers costs only a couple hundred- sound quality.

Likewise with pro PA speakers and yes modern linear array's are designed for the quality of sound. Being able to handle the road is beyond being a given, it's all about quality.

Which JBL's?

i forget which ones he has. they were custom built. bought them from a family friend who has his own studio (also does home theater installs, band gigs, runs a tv station)
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Need help building marine speaker boxes??

Semi-pro ones like the Alesis Monitor one MK2's I'm listening to are made of MDF the is specially built and ordered by the company just for that purpose(not what you get at Home Depot).

Either way you will never design a speaker cabinet that even remotely works or sounds even close to the quality of either one of the above.

I think you are grossly under-estimating the Speaker Building DIY community. Most serious home designers have more tied up in driver measuring eguip, CAD box design S/W, crossover design S/W, and nearfield measuring equipment, that would buy a number of pairs of these Alesis monitors.
 
Top