d. Effect of timbre The identificat

d. Effect of timbre The identification of notes from different instruments presents new situations which are more or less adequately met by the observers. The results from experiments on the pipe-organ using the four stops, viola, diapason, oboe and flute do not reveal striking differences between the average error or the average time per note for judging piano notes and for judging the notes of each of these stops. Since these tests were made after the observers had had several months of practice on the piano, it is possible that some of their methods gained through special practice with piano notes were transferred to the organ notes and aided identification. This may account for the fact that j these observers show less variability than is usually the case in estimating notes of different timbre.