In the Baroque era and Classical period it was usual to use hard mallets, sticks with covered heads being used only for tremolo playing. In the works of Purcell, Bach, Handel and their contemporaries the two kettledrums retained the tuning given at the beginning for the duration of the entire work. In the 18th century the bowls had a diameter of between 41 and 62 cm for the smaller drum and 43 and 65 cm for the larger. The difference in size between the pair was relatively small, a ratio of about 4:3, which remains unchanged today.