Hourglass drums are a sub-category of
membranophone, or
drum, characterized by an
hourglass shape. They are also known as
waisted drums. Drumheads are attached by laces, which may be squeezed during a performance to alter the pitch. The category also includes
pellet drums such as the
damaru, although not all pellet drums are hourglass shaped (such as the Korean
do,
nodo,
noedo, and
yeongdo, which are barrel shaped).