Exotic cabinet materials being considered... should i bother?

[akiwiskibum]

Recently while sourcing materials for my new hifi rack I had the idea of using sandstone for loudspeaker cabinets. Sure they may weigh a ton but i was thinking something along the lines of KEF's Maidstone design where the speaker consists of 3 seperate boxes stacked on top on each other. I'd be looking for a 2 1/2 way biwireable design. Each box will stand on metal spikes raised above the box below.

Actually my brother (who made the wonderful frame for my rack) is a metal worker specialising in spun metal products. He has access to some aluminium housings which are designed to house tweeters in seriously high end setups so I would be making sandstone enclsures for the bass and mid. The amplifier I'll be driving them with is a 100 W AKSA (www.aksaonline.com) which I have almost finished assembling.

Am considering Seas drivers. Preference for fabric tweeters over metal domes. I currently have an old pair of KEF Concorde IV's which have given excellent service and made me quite enamoured with sealed box designs.

My questions are as follows:

Has anyone here tried this before?

Would this be a better solution than using the more traditional but boring MDF and veneer?

Are there any great designs for such boxes to be found easily on the net ? (regardless of box materials)


Greatful for any comments, even if they are telling me I'm insane...

[cyclotronguy]

Don't know if this helps or not! I have a pair of cabinets that have black amphobolite (granite like stone) tops and bottoms. Stone if attached with flooring cement onto MDF. Looks absolutely spectacular, certainly damps resonance.

On the down side, the stuff was $60 US a square foot, and cost a forture to have it machined. I had to pay for breakage of material in machining. Don't think I would do this again! As a side comment, "Damn fine thing I own a forklift!"

Cyclotronguy

[e96mlo]

A local hifi store sells cabinets made of marble. Since there are quite a few different colours of marble available it shouldn't be any problem getting one you like. I think the cabinets are glued together with epoxy.

They look nice!

/Marcus

[thylantyr]

--boring MDF

Try making a design with some curves and use
3/4" thick MDF laminations for box creation. This will look cool,
have alot of mass to kill resonances and top
it off with piano black finish - WOOT!!

I'm doing a hybrid with some laminated sections
inside the main box and the outside. Hard to explain.

[dana]

Sandstone could be aesthetically fabulous. However, you should check out some of B&W’s early papers concerning the efficacy of different enclosure materials (if only because they spend butt loads of money on such things), which they categorized by frequency range. If I remember correctly, concrete was found to be not very desirable for low frequency enclosures, but really good for midrange boxes.

I just started experimenting with this stuff and if you can get it down under, Richlite ( http://www.richlite.com ) is a very promising material for the hobbyist. It is a wood fiber product that was originally developed for Boeing as a tooling medium, but is now used for boat hulls, skateboard ramp surfacing, kitchen countertops and commercial food facilities.

It has all of the primary components one would expect from a legendary and exotic cabinet making material-it is heavy (70 pounds per cubic foot; about half the weight of concrete), it’s dead (wood fiber, resin), difficult to join (needs mechanical or epoxy fastening), it has high compressive, tensile and flexural strength (30, 19 and 22ksi respectively) and it’s relatively expensive (about $15 USD per square foot, one inch thick). It is very easily worked with standard woodworking tools, it cuts, shapes and routes beautifully (makes edge you could shave with) and it doesn’t support the colonization of bacteria (it is NSF Standard 51 certified). Unfortunately, it comes in just three colors- rust, shopping bag brown and construction paper black.

So far, I have only had a chance to play with scrap material and have yet to complete a project with it. But what I can tell you this, it is a lot more difficult to get a clean julienne cut on mdf than this stuff.