Previous measurements [Sharp et al., Proc. Intl. Symp. on Musical Acoustics, 209–214 (1998)] have shown a difference between the profiles of bassoon crooks manufactured in the first half of this century and those manufactured in the second half. Although all the measured crooks have approximately the same initial and final radii, earlier crooks (manufactured by Heckel) typically have a wider bore in the midsection than crooks made more recently (both by Heckel and other manufacturers). Bassoonists have claimed that older Heckel crooks have more desirable playing characteristics than more modern crooks. Psychoacoustical tests were performed to investigate this claim, and to determine whether listeners can distinguish between sounds produced using different crooks. In the tests, players were recorded performing individual notes, scales, and a musical passage on a reference bassoon using a variety of crooks. The crooks were concealed from the players to prevent visual identification. The performers were then questioned about the playing qualities of the crooks. Pairs of sounds produced using different crooks were presented over headphones and listeners were asked to make judgments on the timbres of the sounds. Results from the tests are discussed with reference to the crook profile measurements.