A number of experimental determinations of the uncomfortable loudness level (ULL) at 1000 Hz were made on several groups of normal-hearing subjects, using various methods of stimulus presentation and applying different personality measures to the subjects. The same mean levels were found for both earphone and free-field presentations. In experienced subjects the monaural-binaural difference was between 2.5 and 4 dB in different experiments. In naive subjects this difference was 6 dB. In two groups of subjects, ULL was found to be significantly negatively correlated with their test anxiety scores, but this correlation did not hold for the other two groups tested. Naive subjects showed little difference in intersubject variance with the manual or Bekesy presentation techniques.