Baffle profile – baffle edge problems?

[otto88]

Attached is a draft version about 4 profile for an open baffle design, zipped Excel with a grid to a scale. (If you have problems seeing it, save it then open with Win Zip, extract & open with Excel). It'll be on castors to move easily.

The baffle size and shape is to accommodate several drivers I have, acting as a comparator/ test bed.

Particularly because its large - 2.1 m or 7 feet high – and in an attractive shared room, good looks are important. A large slab of rectangular baffle is not an option. The profile stepping in towards the top, looks like a well known NYC Art Deco building that both my wife and I like.

I know a large roundover is desirable for reducing baffle step, but is the number of corners on the edges a problem?

If it is, I could use transparent extensions of Perspex or similar (as nuuk has done), to smooth the outer shape to similar to one of these
http://www.hawthorneaudio.com/forums...9b2389e#p32865 About three posts below that, is a pic of a wood baffle made in the lower design shape.
That's the inspiration for the curved lines extending out from near the top in my drawing.

Is a curved baffle better than a staggered one?

Cheers

[Ron E]

IMO, when you get into this realm of decorative "art", baffle step should be the least of your worries. How are you gonna cut glass for all those little windows - that is what you should worry about, and where are you gonna get thin stone veneer?

You could try placing some absorptive foam or felt on the top of the steps, and say it is there to simulate roofing or to protect people from sharp corners, or to keep your wife from putting plants on them

If you put the acrylic arches on there, people will REALLY think you are nuts.

[otto88]

Ron,

It would be custom cut, with say three steps.

> stone?
The Cramps’ tombstone inspired look ~ didn’t last long.

> You could try placing some absorptive foam or felt on the top of the steps

Or a Fay Wray/ Nicole Kidman dancing on the spire.

> acrylic arches

Nuuk has done it, it looks ok.

Seriously, will The Edge simulate that shape well, for an open baffle?

Thanks

[otto88]

> acrylic arches on there, people will REALLY think you are nuts

The art deco profile in timber is for looks.

The added single curve per side in a transparent material is to smooth the baffle shape, without adding to apparent bulk, and make the baffle wider for more extended midbass.

Also “stepping out” the width at the bottom to about 500 mm = 20”, allows 18” drivers, a good size for dipoles.

Cheers

[Rudolf]

Otto88,
its VERY unusual to present baffle designs in EXCEL spreadsheets. To me your Art Deco tower looks like this:



I really can´t see were any drivers of what size are going to be on your baffle. Without that information it is almost useless to comment.

Some first impressions:
Even without the acrylic extensions I don´t see any problem with those edges.
You don´t need the extensions reaching to the top of the tower. If they stop at 1 m that would be more than sufficient.
Normally a tweeter would be positioned at ~ 1 m height. At that level the baffle should not be almost 1 m wide.

Confused

Rudolf

[otto88]

Hi Rudolf,

> its VERY unusual to present baffle designs in EXCEL

I know, but at this stage that's the only way I know; how did you turn Excel into a normal image, able to be posted?

> I really can´t see were any drivers of what size are going to be on your baffle. Without that information it is almost useless to comment.

I was trying to focus just on the profile . .

> Even without the acrylic extensions I dont see any problem with those edges

That's what I wanted to know.

> You dont need the extensions reaching to the top of the tower. If they stop at 1 m that would be more than sufficient.

The idea of them running to the top is that’s where the multiple steps are. So each corner * doesn’t add another "diffraction point"?

> Normally a tweeter would be positioned at ~ 1 m height

Yes in this design some are, some are above that, so those above that height will suffer some rolloff, above Hz of? Mmm.

It’s to be a comparator/ plug and play/ test bed – hence eg multiple tweeters etc

As you said it was hard to comment without drivers . .

Regards