But when the congregation
qahal  (kaw-hawl')
assemblage (usually concretely) -- assembly, company, congregation, multitude.
is to be gathered together
qahal  ('kaw-hal')
to convoke -- assemble (selves) (together), gather (selves) (together).
ye shall blow
taqa`  (taw-kah')
to clatter, i.e. slap (the hands together), clang (an instrument); by analogy, to drive (a nail or tent-pin, a dart, etc.); by implication, to become bondsman by handclasping)
but ye shall not sound an alarm
ruwa`  (roo-ah')
to mar (especially by breaking); figuratively, to split the ears (with sound), i.e. shout (for alarm or joy)