Tabo / Dabu-dabu
Tabo is a signaling instrument horizontally suspended in front of mosques. A standard rhythm calls people to prayer on Fridays, while a more intricate tempo is played during Ramadan (Otto 1976 and 1985).
The azhan is the call marking the waktu, time for the salat (prayers) which begin at subuh (early dawn), at luhul (noon), asar (around three in the afternoon), magalib (after sunset) and aysa (early evening). In rural areas, the waktu is signaled by the beating of drums or gongs (Rixhon 1974).
Text: National Museum of the Philippines Website
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