I should know this but don't ... How do I figure out how big a bass trap has to be, to help control a given center frequency?
About halfway back in my room, I get a huge bump around 50-55 HZ.
thanks.
There is a handy program here.
http://www.mh-audio.nl/user/acoustic%20calculator.aspYou can use that to calculate helmholtz resonator dimensions (see my reference to this below). It also has a bunch of helpful functions for diffuser design and calculating room modes.
Rock wool panels or Owens Corning 703/705 (like in Jimna's thread) make effective panels for broadband absorbtion. It probably will be adequate to dampen most of the problems. If you build a corner bass trap that will also address a broadband range of frequencies, but to lower frequencies than panels.
But if there is a lingering problem frequency at the listening position you can build a Helmholtz Resonator to address a specific frequency.
I would try to address any problems with broadband absorbtion first. Then re-measure and if you have a specific mode that is a problem then build a helmholtz resonator to address that.
There is probably lots of info to be found on the net regarding this, but here is one article:
http://www.audioholics.com/education/acoustics-principles/helmholtz-resonant-absorber