Picture Of Felt Around Tweeter

[kingpin]

Anyone have a picture of felt treatment around an Dayton rs28 tweeter?

Should the felt be right up to the edge of the metal screen an the sides and the top and bottom?

How large of an area should the felt cover? 3-4" all around?

Mike

[ThomasW]

A square cutout slightly bigger than the diameter of the dome.

https://web.archive.org/web/20151002182403/http://home.comcast.net/~audio-worx/page90DIY-FeltPads.html

[kingpin]

A square cutout slightly bigger than the diameter of the dome.

https://web.archive.org/web/20151002182403/http://home.comcast.net/~audio-worx/page90DIY-FeltPads.html

Thanks Thomas.
I actually had your page saved in one of my favorites folders but just couldn't find it. It was in the wrong spot.

BTW. How's the curmudgeoning going. :B

[kingpin]

Is this enough area of felt around the tweeter. 2" all around.

Image not available

[JonW]

Mike-

My understanding (from Thomas, actually) is that you have to experiment with this one. And if the grey area in your photo is your felt (not the larger white part) you'll be needing much more than that. It's for absorbing all the tweeter reflections off the baffle. With that little grey area, you'll just get a wee bit of absorption. I'll get to experiment with this some for my ongoing MT project. Let us know your impressions from the felt.

-Jon

[ThomasW]

I would run it to and round the edges of the midwoofers, just like you see in the article I posted.

But as Jon indicated I keep scrap pieces around to experiment with how much is needed/wanted.

If you cover a large area with the felt, it maybe necessary to decrease the amount of attenuation on the tweeter.

[cjd]

FWIW the testing I did had only vertical strips placed on either side, snugged up against the grill.



C

[dlr]

Experimenting is best if possible

Anyone have a picture of felt treatment around an Dayton rs28 tweeter?

Should the felt be right up to the edge of the metal screen an the sides and the top and bottom?

How large of an area should the felt cover? 3-4" all around?

Mike

I have some examples at my site. I'd also recommend the June 2005 issue of audioXpress. It has my article with pictures and measurements that helps to quantify the results of various felt applications and locations.

In general, baffle edge diffraction is best treated with felt that goes to the edge of the baffle, since that is the true source of the diffraction. The felt in between the edge and the driver is used to progressively attenuate the signal that impinges directly on the baffle edge.

The other important application is a piece between the tweeter and any adjacent drivers. Effectiveness is dependent on thickness and depth. The deeper the adjacent driver, the deeper the felt should be to a point.

Your driver separation is fairly large, so the effects are going to be lower in frequency for the driver impact. This usually means deeper felt for maximum effectiveness. However, I found that 1" depth is close to optimal, while there is more variation with the width (distance through which the signal passes). At least 1/2" with 1-2" being closer to optimal.

As a start, I would suggest a piece 3/4" thick, height such that it touches the edges of each woofer and with a rectangular opening, wider than high as seen in your photo. Maybe 1.5/1.0 ratio for width to height for the opening. Even better, have a very slight offset up or down so that the tweeter is not fully centered.

Here's one example of a layout. Note that this baffle has an offset midrange unit. It's also the one used in the audioXpress article.