Cabinet materials - why not more diversity?

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EC8010

EC8010

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Joined 2003
7V said:
So, EC8010, I gather that there's aluminium on the inside and outside with foam in the wall. Is that right?

Also, what do you use for drive-units and how does it sound?

By the way, how near London and which direction?
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Yes, you have that right. The cabinet is denser than you. You will be pleased to learn that it was designed for a Jordan JX92 (you probably guessed that from the volume). 7N7 has made his, but my projects run at a geological pace, so I haven't made mine yet. I thought 7N7s sounded good enough for me to commit money to the idea.
 
pinkmouse

pinkmouse

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Joined 2002
Hi EC8010, I bet they look very cool :cool:

I just thought I would share my experences of this style of construction as i tried it when I was building the bottom end boxes for my current system.

My boxes use the same sort of curved back, only with a solid wood front. I used bendy MDF for the curved walls, and then filled them with expanding builders foam as you did.

However, I was unsatisfied with the sound of the boxes, and when I dismantled them for a rebuild, I found voids in the fill, some as big as 40 or 50mm across, and areas where the foam had barely expanded and was very solid. From this experience I hypothesise that you have to be very careful when filling to both avoid any trapped air, and get an even distribution of the foam to avoid the consistency problems I had.
 
EC8010

EC8010

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Joined 2003
pinkmouse said:
From this experience I hypothesise that you have to be very careful when filling to both avoid any trapped air, and get an even distribution of the foam to avoid the consistency problems I had.
Click to expand...

Sadly, you are right on the money there. That's exactly what 7N7 complained about on his first attempt at filling. I wondered if it was a chemical reaction between the aluminium and the foam, but if you had the same problem with MDF that seems unlikely.
 
purplepeople

purplepeople

Member
Joined 2003
Harman Kardon Soundsticks

I think this is some kind of acrylic.

:)ensen.
 

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EC8010

EC8010

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Joined 2003
purplepeople said:
But it looks a lot the sub uses a sealed box for the forward firing wave and a rear ported horn in combination with it.
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Tricky. I magnified it, and it looked like an X-rayed condom. More seriously, it looks like a horn feeding a reflex port. Goodness only knows what that is supposed to do, but I suspect that your comment, "I only saw them at a computer store," says all that is necessary...
 
EC8010

EC8010

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Joined 2003
Distributed Mode Loudspeakers have their problems, there's a thread on this forum about them.

It's as well to make it quite clear that the illustration shown is a photograph of the NXT loudspeakers, but the images of woofer and tweeter are just that. Printed images on the cardboard.
 
planet10

planet10

frugal-phile™
Joined 2001
planet10-hifi.com
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EC8010 said:
I'm not clear about your acrylic example. Is it a horn from the back of the drivers? It's difficult to tell what it is from the (necessarily limited resolution) picture.
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The "Jellyfish" subwoofer was designed by Harkon Kardon to aid the bottom on the iMac (rev E & up) that have the 25mm FR (JBL)

An externally hosted image should be here but it was not working when we last tested it.


(http://www.t-linespeakers.org/drivers/iBall/index.html]more info & waterfalls[/URL] )

The one pictured above is the Harmon version (larger woofer), and an array of 4 of 25 mm FR.

dave
 

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