(UK, informal) wholesome; reliable; in good condition

(sound, headphones) the property of blocking off outside sound through use of materials that reduce sound transmission from the exterior environment into the interior environment

Perfectly sound.

plural of sound post

(photography) A housing attached to a camera in order to reduce the shutter click sound.

present participle of sound out

simple past tense and past participle of sound out

Third-person singular simple present indicative form of sound out

plural of sound head

A component of a film projector or similar device that reads or writes audio signals in electromagnetic form.