Welded steel frame sand filled enclosure

[JoeM]

For me this is much cheaper, much quicker, much easier than MDF. But is it better?
Im thinking a welded 30mm by 30mm by 2mm thick square tubing for the frame lined with 1mm sheet metal panels on the inside and out and the cavity and all tubing filled with sand. Front panel 25mm MDF.

How do you think this compares sound wise to a standard build 25mm MDF box for a floor stander like this?

[Pano]

Compare? Dead heavy. Heavy and dead.

Never heard sand filled steel cabs, but sand filled ply are the best I've heard - or not heard, as the case may be.

Internal reflections might worry me a bit.

Will be interesting to see what other posters think.

[gtforme00]

It certainly seems like solid construction, I don't see any disadvantages of your method, except for the weight and complexity to build (for me, if you say it's easier for you then all the better!)

You'll probably still want to put some fairly dense stuffing in the lower portion of the enclosure to help damp standing modes due to the geometry.

-David

[Moondog55]

I can see a small problem if the diagonal bracing is the same profile as the uprights; how is the sand going to flow thru to fill all of the voids?

I can't weld for nuts so I would be intimidated by the proposal.
Are the diagonals actually needed in a welded construction? and are you going to use rustproofing before adding the sand as corrosion may be a long term problem.
I can imagine these in brushed stainless steel how-ever SEXY!

[picowallspeaker]

Hey ! Those speakers have collapsed to their stands !!

[JoeM]

Panomaniac,
Wouldnt internal reflection be the same in a timber construction of the same dimensions?

Moondog55,
I didn't draw it but the tubing and particularly the bracing will have 10mm holes drilled here and there for the sand. Definitely rustproof and I will ensure the sand is ultra dry. Stainless WILL be tempting...

Will this concept be ok for a sub enclosure?

[Pano]

Well, yeah - the wavelengths should be the same. It's just that metal is so much more reflective than wood.

I'm sure there is some wise-guy here who will say "oh no it's not" and spout proofs. But I've been inside metal boats and wooden boats - I know which one reflects more sound!

But it should be easy enough to kill those reflections, just have to be sure to do it!

[CLS]

How about just leaving it OB and showing the frames?

I'm working on a similar framework for OB bass and mid horn, just not steel tubes, timbers instead.

Before I started building the timber framework, I thought of aluminum extrusion parts. Those are also very strong and very cool looking.

[56oval]

Hi Joe
Instead of using box section for the diagnals use solid round .
Cheers

[Peter M.]

Why diagonal? If you make them straight across it will be stiffer.