Baffle 36mm thick, do i need to chamfer?

[iampivot]

I've just finished routing my baffles (2x18mm) for my ZRT 2.5 way sealed.

Should I do a 45" chamfer around the the woofer, or can I just use the same 1/2" rounding bit as i'll use on my baffle edges?

 

[planet10]

I would suggest a big champher is necessary if you want to avoid cavity resonance from screwing up your mids.

dave

 

[tvrgeek]

Round vs. camber. Two issues, you pick. Camber will have a sharp edge that is libel to produce refraction. Round over a bit more restrictive so if you expect really large cone excursions, maybe an issue.

I camber, then hit it with a flapper disk and smooth everything out trying for a horn-like profile.

 

[leadbelly]

It's CHAMFER not camber, champher, or camfer!

 

[planet10]

It's CHAMFER not camber, champher, or camfer!

Champher & camber are both correct, chamfer would be an americanization of champher.

dave

 

[David Gatti]

Once you chamfer the chamber you can clamber for some champagne, champ.

 

[planet10]

 

[awpagan]

With the baffles, is there any minuses using 2x18mm mdf, instead of one piece 36mm?

I know it's hard to find large thickness mdf, the thickest I can find locally is 32mm.
But the suppliers can glue two thickness's together for me.

ps I did chamfer a 45 deg camber for woofer in a 25mm baffle

 

[planet10]

2 layers of 18mm MDF are likely better than 1 x 36. 3x 12 would be better yet. 2 x 12mm of quality plywood even better.

dave

 

[CCU]

YES!

Troels gravesen did a big write up on the matter. I can't find it right now though

 

[Silent Screamer]

This raises an interesting question about how thick is the "ideal" baffle?

While thick is more stable, a big right angle wall close to the speaker cone can’t be good for clearing the sound waves.

Reccessing the drivers helps because it reduces the baffle thickness, but I wonder if there is some kind of formula to be applied.

 

[tvrgeek]

Depends on many other variables. How much stiffness does the basket provide? Is it rigid to the baffle or compliant coupled, where the cutout is, what is the depth of the cone, and on and on and on. It is a design issue, no simple answer.

I would not call the problem "clearing the sound waves" It is more like reducing reflections.

 

[awpagan]

planet10 & CCU
Thank you for the response.

 

[planet10]

This raises an interesting question about how thick is the "ideal" baffle?

Thin & stiff. And not completely straightforward as TVR suggests. A subbaffle of aluminum is a good solution.

dave

 

[tvrgeek]

I have actually used a ceramic plate epoxied between plywood and MDF for a sealed sub cabinet. Very effective. Multiple materials are good for anti-resonant. Tile very stiff. Wood very low Q. No one said making a good speaker was easy. One of these days I will make one with the tile the exposed front. Routing the recess will be the challenge.

For a monitor, using plastic laminate or aluminum skin on both side adds tremendous rigidity to allow a thinner panel. Heck, even the melamine skin for cheap shelves adds strength.

 

[lrntglls]

I use 3 panels of birch plywood with green glue between each panel. 2X19mm+1X25.4mm.
The driver is even with the front baffle and the back of the front baffle hole
is at an angle. Very massive.

 

[planet10]

Chris just built a test mule for push-push SDX10. All 15mm BB. I'm curious as to how effective the push-push really is at reducing box load. After the test, we will add a skin of 18mm to the baffles (at a minimum) to flush mount the drivers.

dave

 

[chrisb]

we just built a test mule for push-push SDX10. All 15mm BB. I'm curious as to how effective the push-push really is at reducing box load. After the test, we will add a skin of 18mm to the baffles (at a minimum) to flush mount the drivers.

dave

Dave will hopefully be installing drivers (which by my estimate will have more mass than the initial boxes)

 

[tvrgeek]

Easy to get carried away with the cabinet and forget the crossover is 90% of the results.

 

[pski]

I've just finished routing my baffles (2x18mm) for my ZRT 2.5 way sealed.

Should I do a 45" camfer around the the woofer, or can I just use the same 1/2" rounding bit as i'll use on my baffle edges?

Hi,

Built the vented versions and they are still here. The designer says yes. I would do the 45 degree. Ace Hardware has a bit for less than USD 10.

Post more pictures.

https://www.facebook.com/media/set/?set=a.2198606537629.119347.1621248869&type=3&l=6334890e9d



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