A canal hearing device with a dual acoustic seal system for preventing
feedback while minimizing occlusion effects. The two-part device
comprises a main module and an elongated tubular insert for conducting
sound to the tympanic membrane and sealing within the bony region of the
ear canal. The main module is positioned in the cartilaginous portion of
the ear canal. The tubular insert comprises a sound conduction tube and a
cylindrically hollow primary seal medially positioned in the bony region.
The device also comprises a secondary seal laterally positioned in the
cartilaginous region. The secondary seal, although providing additional
acoustic sealing for the prevention of feedback, is sufficiently vented
to provide a path of least acoustic resistance for occlusion sounds
within the ear canal. In a preferred embodiment, the tubular insert
comprises a coiled skeletal frame to provide high radial flexibility
while maintaining sufficient axial rigidity for comfortable,
kink-resistant, and consistent placement within the ear canal.