This paper discusses a partially completed project that was begun shortly before an unexpected retirement opportunity appeared that limits the possibilities for follow-up work. The project was to investigate the pitch of door closing “thump.” The impetus for the investigation was a paper by Gardner and Magnasco. Their paper described an instantaneous frequency decomposition method that they used in the study of bird song and human speech. Bird song or speech may not seem to be closely linked to measuring door closing thump but the speed with which the frequencies in door closing sounds change is not that different from the speed of frequency change in bird song or speech. Two questions that immediately arise are can Gardner and Magnasco's technique resolve the low frequency components that occur in door closing sounds and, if so, do they relate to human perception of thump? This paper can only present a brief look at the encouraging results from preliminary work to answer the first question. Further work is needed to completely answer the two questions and either confirm or reject the technique.