By Pittsburgh Symphony Orchestra’s principal oboist Cynthia Koledo DeAlmeida estimates she spends six to eight hours a day, six days a week crafting reeds. They affect sound, pitch, tone, response and comfort so, “really good oboist are usually really good reed makers,” Ms. DeAlmeida says. One in five or ten reeds she makes is suitable for a performance and they can only last for two or three concerts and a rehearsal.