Why Pitchers Are Needed
According to Sacred Harp scholar Buell E. Cobb, the notation of Sacred Harp songs is often a notation of convenience, arranged to keep the notes within the staff on each part, minimizing the use of ledger lines. It is feasible to switch keys at the moment of singing because Sacred Harp singing is an a cappella tradition; hence there are no instruments that would have to transpose on the spot, often a difficult task. Most singers transpose effortlessly.
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