CPC Subgroup Additional Only
H04R 2209/026 Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice (H04R2400/03 takes precedence)
Full Title
Details of transducers of the moving-coil, moving-strip, or moving-wire type covered by H04R9/00 but not provided for in any of its subgroups > Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice (H04R2400/03 takes precedence)