Quarter wavelength trap

[NYMorningstar]

This trap uses an enclosure with a depth that is 1/4 the wavelength of the offending bass frequency. If I leave 4 speaker columns unused and standing along the backwall of my studio that are only 1 foot deep, does it hold true that these will trap midrange wavelengths? Will it prevent this by just turning the openings away from the sound or should I remove them from the room altogether?

 

[TexRoadkill]

They should provide some type of absorption and difraction but exactly how much is hard to say. If they seem to help the sound then keep them in there. You might stack them in the corners to help break up flutter echoes.