lightweight enclosure materials

CHRIS8

Disabled Account
2001-12-12 8:47 am
VA, USA
I would use a 10" PVC pipe, rip in half, use a3/4" or 1" MDF baffle...rabbet the edges so the PVC fits onto a lip, and cut a top and bottom out of MDF also. Their you have it, a very strong, and relatively light enclosure.

Only problem is the cost of the PVC. I think that 10" is only available in 8 or 10 foot sections? You could get lucky..call the local plumbing supply and see if they have some scrap.

Just an idea.

-Chris
 
Somebudda stop me!! How 'bout sonotube? I know people make telescope tubes out of it,though I'll have to check on how they finish it to make it stiffer and weather-resistant(I also have a piece of 10 inch in my garage,so I want it to work.)
Seriously,I love brainstorming,and appreciate the responses.Fiberglass brings back unpleasant memories of long-ago auto body repair attempts.But please,keep 'em coming.
John
 
jbrom said:
Dave-any chance of getting sketches of your design ideas? I can't quite picture what you mean.

I didn't really have a box shape in mind -- just a construction method. Your box sounds like it is going to be fairly small so a rectangular box with 35mm strip braces (running the long dimension -- ie dividing panels into long skinny areas -- even better if they are at an angle dividing the panelsinto trapezoids).

By stressing the panels into a curve, even a slight one, the bracing could be left out -- a harder box to make, but lighter.

dave
 
Aluminum

Gallo (www.roundsound.com) made the Nucleus units (not to be confused with the new small cheap stuff).

1. Generation: Fiberglass -- inexpensive, proably not all that effective.
2. Generation: Thin, "worked" Aluminum -- anodized. Work hardening of the metal + consider that Aluminum Oxide is a ceramic was supposed to move resonances beyond 20KHz. It worked quite well.
 
The Gallo stuff looks neat. I read the reviews and started looking around for spheres.I found hard hats.Light,rigid,but kind of a tight fit for 6x9s. 2 layers of MDF at the opening could give me about 7" of depth,which is close to what some of the commercial enclosures have.The opening is not flat,but I'm sure that can be accomodated.If I had MDF on hand I'd be starting now.I know nothing about proper enclosure sizing,and I don't know if car speakers have published T-S parameters,which I think is where one starts,if one has a clue.For myself,I'm a beginner,but I'm willing to take a shot.
J
 
Avoid fiberglass ... unless you are very experienced at using it and have the appropriate materials and can take necessary precautions to protect yourself ... lots of professionals who wear respirators while they work often still end up with serious health problems from it. You would actually be better off looking into Carbon Fiber.
 

CHRIS8

Disabled Account
2001-12-12 8:47 am
VA, USA
"Chris and Dave-any chance of getting sketches of your design ideas? I can't quite picture what you mean. "

Here is an example:)this would work great with your leftover sonutube also, plus sonotube is much easier to work with).

(Note: baffle is 1" in this image, pipe wall thickness is exaggerated)

[IMGDEAD]http://64.33.91.28/images/6x9.gif[/IMGDEAD]

http://64.33.91.28/images/6x9.gif

-Chris
 
Thanks,Chris.That's easy to follow.I took a couple of hours off this morning and tried my brilliant hard hat idea. Excitedly hooked everything up and guess what-it sounds like two speakers in plastic cans.Maybe I should be on diyAudiodoofus.Oh,well.I do have some MDF.Next chance I get,I'll try your idea,Chris.It looks simple.Do you recommend sound-deadening material,or batting inside?
John
 

CHRIS8

Disabled Account
2001-12-12 8:47 am
VA, USA
"Do you recommend sound-deadening material,or batting inside? "

Well, probably a little acoustic foam on the walls, and just polyfill, fiberglass or dacron filler.

Regardless, the speaker is likely going to have a little bit 'honky' bass, as almost all car speakers(door, dash) are optimized for infinite baffle use. Just increase internal volume to the maximum that you can allow.

-Chris
 

jwv3

Member
2002-03-04 2:12 pm
DE
Are you trying to keep it simply and quick to build, or do you have plenty of time to throw at it?

How about light ply, like around 1/4 to 3/8" and brace the daylights out of it. I'm thinking internal brace structure resembling the arches and lattices of bridge supports. Of course it wouldn't be the quick way out.

The half tube idea mentioned above is clever.
 
I don't have a lot of spare time these days.My original goal was to put together a higher-quality CD/radio than I could buy, that would be rugged enough to take to work.I'm a carpenter,and make lots of dust on the job.I put the head unit and power supply in a 24" long toolbox.I wanted to mount speakers in the box,too,but when I auditioned some I really wasn't satisfied with smaller than 6x9.I'd like something that I can transport in one trip-I feel kind of silly coming into someone's house with armloads of audio equipment.You get the picture.So I want the enclosures to be as compact as possible,but I sense that they need to be a certain volume to sound OK.So here I am.I might try Chris's idea,or I might just break down and buy ready-made enclosures until I can free up some time.
John
 
jbrom said:
I might try Chris's idea,or I might just break down and buy ready-made enclosures until I can free up some time.

I like Chris' idea too. For transport they could have latches on the side and snap together face-to-face with a carry handle somewhere.

You could ameriolate the size somewhat by making the cabinet aperiodic. My algorithm for such a thing is:
1/build a sealed cabinet as large as you figure you can get away with (assuming here that it is still smaller than an ideal sealed box).
2/ at the farthest convienent point from the driver, drill a number of holes (1"/1.25") with an equivalent area to the driver's Sd.
3/ behind this tightly place solid acoustic foam (i actually get away with salvaged open-cel packing foam -- despite that this is "officially" not at all the same as acoustic foam). Alternatively, put a rebate of about a 1/2" on top of the holes and compress fiberglass insulation into this rebate over the holes (1.5" compressed to 1/2' seems about right) and hold it in place with a mesh (ie the plastic stuff used from keeping crap out of your gutters)
4/ fill the box with poly fluff, acousta-stuff or whatever to make the box as large as you can.

dave