Carefully filtered 250 and 500 cps tones were mixed in various phase relations, producing wave forms which are not symmetrical about the time axis. By commutating the leads to an earphone it is possible to present the resulting complex tone to the ear with a given half either a condensation or a rarefaction. Subjects attempted to distinguish between the two presentations. The 250‐cps fundamental ranged in SPL from 40 to 84 db and the 500 cps harmonic from below threshold to 73 db. For each combination of levels and phase, a random sequence of twenty presentations was used, half with the commutator in one position and half in the other. The one‐second stimuli were separated by one second of silence. The results show that subjects can not only detect a difference between the phase‐reversed signals but can identify one as “higher” or “louder” or “muffled.” The two subjects from whom most of the data were obtained responded under many conditions with 80 to 100% consistency. For some of these conditions the subjects agreed about which phase condition was higher (or louder); for others they disagreed although remaining self‐consistent. The results will be shown to have some bearing on the “best‐beat” controversy. [This work was partially supported by the Bureau of Ships.]