Studying the directivity of musical instruments such as pipe organs is challenging because of their great size and because they typically cannot be moved from the locations where they are built to the laboratory. This study compares the radiation pattern of organ buffets under different excitation conditions, using a 19th century French pipe organ. We investigate the positive and the great organ independently due to their spatial separation and size. The excitation strategies were comprised of cylindrical and an omnidirectional electroacoustic sources. Measurements were carried out on each organ buffet along a horizontal line spanning the width of the church. Results in octave bands are shown and compared with a discussion on possible causes for observed differences. Significant variations in directivity were observed for the 2 kHz to 4 kHz octave-band regions where scattering from pipes is expected to have a predominant effect, while little variation from omnidirectional was observed for lower frequency bands for both sources.