absonant
atonal
cacophonous
cracked
diaphonic
disconsonant
discordant
disharmonic
disharmonious
dissonant
flat
grating
harsh
immelodious
inharmonic
inharmonious
musicless
nonmelodious
off
off-key
off-tone
out of pitch
out of tone
out of tune
raucous
rude
sharp
shrill
sour
strident
tuneless
unharmonious
unmelodious
untunable
untuned
untuneful
bell-like
doleful
ear-splitting
guttural
lugubrious
nasal
sibilant
sonorous
throaty
tinny
toneless
unappreciative
uncomprehending
ungrammatical
uninterested
wordless
musical