The records played on these gramophones were very different from the black vinyl platters that later became so familiar. The primary material was instead shellac, made from the secretions of a Southeast Asian insect. Because they turned at a rate of 78 revolutions per minute (rpm), they were also nicknamed "78s."
留聲機所適用的唱盤，也不同於後期人們熟知的黑膠唱片，而是用一種俗稱「膠蟲」的東南亞昆蟲的分泌物為主要原料製成，所以又稱「蟲膠唱片」，由於 1 分鐘固定轉 78 圈，又稱為「78 轉唱片」。