Beyond the major-minor tonality that characterizes classical and contemporary Western musical genres, Turkish classical and folk music offer experimental psychologists a rich modal system in which cognition, development, and enculturation can be studied. Here, we present a cross-cultural experiment concerning implicit knowledge of musical scales. Five groups of participants—American musicians and nonmusicians, Turkish musicians and nonmusicians, and Turkish classical and folk music listeners—were asked to listen to brief melodies composed using the member tones of either the major scale or the (...) rast makam, a microtonal mode found within Turkish classical and folk genres with no equivalent in Western music. Following each melody, participants were asked to identify whether a probe tone had been presented in the melody, providing confidence ratings on a six-point scale. In general, participants’ short-term memory was influenced by implicit knowledge of musical scales, with the major scale eclipsing the rast makam even in listeners experienced with Turkish genres. Prior work and future directions in cross-cultural music cognition research are discussed. (shrink)