Baffle for waveguide testing

[Ed LaFontaine]

I have some size limitations so I don't want to make a test baffle any larger than it has to be. This is to be used in testing various waveguide profiles with dome and ring radiator tweeters. I expect the usable low end will be, say ~1100-1200 hz.

If the baffle is made 1'-7" outside the waveguide (almost 4 feet in diameter), will diffraction artifacts be around 700 hz or lower? Is this baffle large enough to provide usable results?

 

[mazurek]

I'm interested in this too, diffraction seems like an important variable in waveguide testing.

 

[ralphs99]

Hi Ed,

In my waveguide tests I used a 0.5m square baffle. I didn't see any diffraction artifacts down to at least 1.5kHz. (I didn't test any lower)

I think that a 4' square baffle will be fine. Just make sure that its not round!

You can see my results at: http://www.aeronet.com.au/waveguide.htm

Cheers, Ralph

 

[mazurek]

Thanks, by the way, I read your site, just forgot you had baffle info.

 

[soongsc]

I would recommend testing waveguides free standing or exactly the baffle configuration that is going to be used in real application. This assumes the waveguide is existing design and not being modified.