In this instrument, the sound is obtained by
placing the lips on a hole bored through the
peaked end of the conch and blowing through it.
In sue since the Koryo period, this instrument was employed
largely in military-type ceremonies and processionals, but it was also,
at one time, used in royal ancestral shrine music. Today, it forms part
of the processional music ensemble along with that of the conical
oboe(t'aep'yongso),clarion, large gong, cymbals, and dragon
drum(yonggo). Like the clarion, it plays no melody, but merely emits
one long, low, sustained tone, something akin to that of a fogelson,
that has a wide and slowly reverberating vibrato.