An earphone or adapter for attaching to an earphone includes an ear portion including a tubular sidewall. In one embodiment, the tubular sidewall includes an inner surface defining an air channel extending through the sidewall. The air channel redirects sound at an angle to the speaker axis, and may have a smooth contour to maintain sound quality. In one embodiment, the inner surface has a twin cone shape including a converging cone portion extending from the first end and a diverging cone portion extending from the converging cone portion to the second end. The outer surface of the tubular portion may include a plurality of outwardly extending fins In one embodiment, the tubular portion includes both a plurality of fins, and a twin cone air channel.
