Acoustics Patents (Class 181)
- Moisture proof (Class 181/149)
- Recessed (e.g., wall-mounted, etc.) (Class 181/150)
- With sound-absorbing means (Class 181/151)
- With horn (Class 181/152)
- Rounded enclosure (e.g., curved, etc.) (Class 181/153)
- Inclined diaphragm (Class 181/154)
- Reflector baffle (Class 181/155)
- Reflex baffle (Class 181/156)
- Microphone type (Class 181/158)
- With horn (Class 181/159)
- With resonant chamber (Class 181/160)
- With direct mechanical connection to drive unit (Class 181/161)
- Plural dependent diaphragms (Class 181/163)
- Sectional diaphragm (Class 181/164)
- With damping means (Class 181/166)
- Critically defined material or coating (Class 181/167)
- Mounting or suspension means (Class 181/171)
- Particular shape (Class 181/173)
- Lens (Class 181/176)
- Intensifying horn (Class 181/177)
- Within tubular means (Class 181/196)
- Housing or enclosure (e.g., sound confining and absorbing) (Class 181/198)
- By wave interference (Class 181/206)
- Mechanical vibration attenuator (Class 181/207)
- Sound absorbing fence or screen (e.g., jet engine or vehicle noise) (Class 181/210)
- Combined (Class 181/211)
- Muffler, fluid conducting type (Class 181/212)
- Sound absorbing panels (Class 181/284)
- Space absorbers (Class 181/295)
- Methods (Class 181/296)
