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Thoughts on attenuating 1/4 wave cancellation

Among other things, I would like to address the 1/4 wave cancellation coming from the wall behind my speakers. I would like to avoid soffit mounting, as that would require building a new wall, and after all of that I would end up with a fixed speaker position.

My room is solely for audio, so I need not worry about aesthetic issues arising out of bass trap placement. If I were to place a big (e.g., 24" diameter) ASC tube trap against each side of the speaker, and maybe one more behind and to the outside of each of these, it seems to me that the bass waves heading backwards would be significantly attenuated and the cancellation would be significantly reduced. This might help reduce edge diffraction, too, but I am far out of my element with most of these acoustic phenomena.

I am hoping that someone can debunk this notion before I buy the extra tube traps and discover the hard way that it was a boneheaded idea.
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Showing 1 response by almarg

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almarg
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Good questions from Zargon. Also, are the speakers dipolar, front-firing, other? And how far down does their low frequency response go?

Also, I could be wrong but I believe it is more correctly referred to as 1/2 wave cancellation. The path from the speaker to the wall behind it would be 1/4 wavelength at the affected frequency, then another 1/4 wavelength for the reflection to return to the plane of the speaker, where it would be a total of 1/2 wavelength or 180 degrees out of phase with the forward-radiated waveform, resulting in cancellation.

-- Al
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