In this study we constructed a special three-in-one resonance tube for a harmonic series sound waves
experiment. It is designed for three different experiments: both-open-end, one-closed-end and
both-closed-end tubes. The resonance tube consists of a PVC conduit with a rectangular hole, rubber
tube, plastic stopper with an embedded microphone and a plastic stopper. The resonance tube is
utilized with visual analyser freeware to detect, display and measure the resonance frequencies for
each harmonic series. The speeds of sound in air, v , are determined from the gradient of the
##IMG## [http://ej.iop.org/images/0031-9120/52/4/045008/pedaa670bieqn001.gif] {$2(L+e)$} versus
##IMG## [http://ej.iop.org/images/0031-9120/52/4/045008/pedaa670bieqn002.gif] {$n\,f_{n}^{-1}$} ,
##IMG## [http://ej.iop.org/images/0031-9120/52/4/045008/pedaa670bieqn003.gif] {$4(L+e)$} versus
##IMG## {$n\,f_{n}^{-1}$}