WordNet sense 1 (conspicuously and offensively loud; given to vehement outcry):

blatant, clamorous, strident, vociferous

WordNet sense 2 (full of or characterized by loud and nonmusical sounds):

noisy

WordNet sense 3 (demanding attention):

crying, exigent, insistent, instant

WordNet sense 4 (requiring attention or action):

imperative