WordNet sense 1 (tastelessly showy):

brassy, cheap, flash, flashy, garish, gaudy, gimcrack, meretricious, tacky, tawdry, trashy, tatty

WordNet sense 2 (used chiefly as a direction or description in music):

forte, forte

WordNet sense 3 (loud enough to cause (temporary) hearing loss):

roaring

WordNet sense 4 (loud and firm):

big

WordNet sense 5 (attracting attention by showiness or bright colors):

noisy

WordNet sense 6 (striking in variety and interest):

colourful

WordNet sense 7 (with relatively high volume):

aloud, loudly