low-toned

from WordNet (r) 3.0 (2006)

low-toned
    adj 1: very low in volume; "a low murmur"; "the low-toned murmur
           of the surf" [syn: {low}, {low-toned}]

from The Collaborative International Dictionary of English v.0.48

low-toned \low-toned\ adj.
   relatively low in volume; soft; -- of sound; as, making
   low-toned noises with their mouths that went as an
   undercurrent of sound. Opposite of {loud}.

   Syn: low, subdued, soft.
        [WordNet 1.5]