ariel question

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the ariel calls for 3/4'" mdf for the sides,top,rear...pretty much the entire outside of the enclosure. my question is,...i dont want to use mdf i would like to use all birch or birch for the tl and fiddle back maple for the sides, top, and so on. will using a hardwood for the sides be a bad idea since it has diferent acoustic caracteristics than mdf?
thanks....shallenn
 
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Premium MDF seems to be the magic material for speakers. They use it because it is best-not because it is cheaper. Pretty much everything about the Ariel has been agonized over and the latest version is the best.

With the rounded front corners I would think you could do a super veneer job that would look like solid wood but maybe better matched and more exotic grain if desired. The top cap is solid wood though!
 
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Hi,

I have been using MKII Ariels since 1997, and they were built according to the plans. However, I remember reading in Lynn's text that a cabinet of all baltic birch should work just fine. This is mentioned in the "exterior panels" paragraph in the cabinet construction section
 
go with MDF

MDF is one of the best materials because it is (relatively) acoustically "dead". Most hardwoods are too resonant to be acceptable for loudspeakers. You definately can find(and buy) more acoustically dead materials than MDF, but then you run into the whole "diminishing returns" thing both financially and in terms of effort. I have heard of people using concrete, marble or slate, but they require special(expensive) tools and a hell of a lot of patience and time. MDF is so popular because it is quite cheap, and easily shaped and finished, as well as it's excellent non-resonant properties. If you still want the hardwood look, you should either veneer it yourself, or, to be safe, try to find some pre-veneered sheets of MDF.
 
I cannot find the specific reference right now (I hate when that happens!) but MDF is primarily used because of low cost and easy availability. It is better than hardwoods, but certain plywoods are much better than MDF in terms of rigidity and resonance.

9-ply Baltic Birch, Apple ply, or Marine grade ply are all superior to MDF for speaker enclosures. It is important to make sure that you use top grade (no-void) plywoods. Each of these materials are easily twices as expensive as standard MDF. There was just an article in the Feb 2002 AudioXpress about enclosure materials...

The conclusion of the article basically indicated a few points:
1) hi-grade plywoods are better than MDF
2) Using multiple layers of wood is better than a single thickness for the cabinet wall
3) Heavy internal bracing in the form of wood squares with circular cutouts are best

Eric
 
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The Ariel doesn't use it for cost or availibility. Using Premium MDF is actually more hassle. They are full of quality plywood on the inside, so putting it on the outside would be no big deal. Lynn has told some people that using ply on the outer walls is not a huge problem, and that they will probably function fine, but he seems to think the MDF has superior damping characteristics.
Maybe he is wrong, but that is his opinion as the designer from my reading of the website.

I think most people agree that solid wood is not as good as ply or premium MDF
 
i didnt want to hastle with mdf on the sides and try to pancake another ply or hard wood on top of it. i will probably end up buyinga wholesheet of birch so might as well use it where ever i can! i definetly want wood on the outsid wether it be ply or solid.
as for the internal damping.......i may have a problem finding wool, still working on that but how about the white cellulose used in attic insulation? would this work for a damping material? and how do you keep it from falling down into the tl?
thanks.shallenn
 
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shallen,

If you can't find wool, probably the next best and easier to find material for stuffing the line would be dacron fiber fill, found at fabric stores. The dacron actually supports itself better inside the line than wool. I found wool at a local craft store that specialized in weaving, knitting and quilting supplies.
 
Ariel

I built Ariel's about two years ago using 3/4 inch engineering grade plywood; and think the question of MDF / Baltic ply for this project is a non issue. The question is more of quality construction. The Ariel is braced such that resonance problems just do not become an issue.

cyclotronguy
 
Wool felt replacement...

Guys,

I've just collected all the material for building Ariel 6c, except for the F13 wool felt (to be attached on some parts of labyrinth panel), as specified by Lynn Olson, the best damping material for Ariel.

However, it's very hard to find F13 wool felt here in Indonesia.... Not just hard to find, but NONE. The only place where I can find it is at www.mcmaster.com, but the shipping cost is ridicilously expensive ($34).

After digging Ariel Builders club links, one builder in holland said that a thick carpet will do just find to replace the F13 wool felt. Anybody tried replacing/comparing the wool felt with thick carpet? How thick should the carpet be?

Also, Lynn specified that the Wool felt should be F13 specs, 85% density (or more). But if we look at mcmaster catalog, F13 is only 75% in density. If 85% is a must, then the right specs is F11, not F13. I wonder if Lynn made a mistake about this....

Cheers,
 
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