Disclosed is a ring shaped wearable communication device (ring) for a user's finger. The ring includes: a sound sensor that detects ambient sound levels; a speaker that produces sound in human audible frequency range per at least one signal received, wherein intensity of the sound produced is based on the ambient sound level; an out port; and a hollow channel with an increasing cross-section that wraps around the finger, wherein: smaller cross-section end of the hollow channel is connected to the speaker and the other end of the hollow channel is connected to the out port to provide a horn-like structure; the out port and the hollow channel are configured to reduce the mismatch between the acoustic impedance of air immediately outside the out port and the acoustic impedance as seen by the speaker just outside the speaker; and the out port emits sound received from the speaker as directional sound in close vicinity of the user's hand.